Maurice Herlihy - mwini awiri Mphotho ya Dijkstra. Yoyamba ndi yogwira ntchito "Kudikirira Kwaulere" (Brown University) ndipo yachiwiri, yaposachedwa, - "Transactional Memory: Zomangamanga Zothandizira Zomangamanga Zopanda Lock-Free Data" (Virginia Tech University). Mphotho ya Dijkstra imaperekedwa chifukwa cha ntchito yomwe kufunikira kwake komanso mphamvu zake zakhala zikuwonekera kwa zaka zosachepera khumi ndipo Maurice mwachiwonekere ndi m'modzi mwa akatswiri odziwika bwino pantchitoyi. Pakadali pano amagwira ntchito ngati pulofesa ku Brown University ndipo ali ndi zambiri zomwe wakwaniritsa zomwe ndi ndime yayitali. Pakali pano akufufuza blockchain mu nkhani ya classical anagawira kompyuta.

M'mbuyomu, Maurice anali atabwera kale ku Russia ku SPTCC.kanema tepi) ndipo adapanga msonkhano wabwino kwambiri wa gulu la omanga JUG.ru Java ku St.kanema tepi).

Habrapost iyi ndi zokambirana zabwino ndi Maurice Herlihy. Imakambirana mitu iyi:

• Kugwirizana pakati pa maphunziro ndi mafakitale;
• Maziko a Blockchain Research;
• Kodi malingaliro opambana amachokera kuti? Chikoka cha kutchuka;
• PhD moyang'aniridwa ndi Barbara Liskov;
• Dziko likuyembekezera multicore;
• Dziko latsopano limabweretsa mavuto atsopano. NVM, NUMA ndi kuwononga zomangamanga;
• Ma compilers vs processors, RISC vs CISC, kukumbukira kukumbukira vs kudutsa uthenga;
• Luso lolemba zolemba zosalimba zamitundu yambiri;
• Momwe mungaphunzitsire ophunzira kulemba ma code ovuta amitundu yambiri;
• Kusindikiza kwatsopano kwa buku la "The Art of Multiprocessor Programming";
• Momwe kukumbukira kwamalonda kudapangidwira;   
• Chifukwa chiyani kuli koyenera kuchita kafukufuku m'munda wamakompyuta ogawidwa;
• Kodi kukula kwa ma aligorivimu kwayima, ndi momwe mungapitirire;
• Ntchito ku Brown University;
• Kusiyana pakati pa kafukufuku ku yunivesite ndi mkati mwa bungwe;
• Hydra ndi SPTDC.

Interview imachitidwa ndi:

Vitaly Aksenov - pakadali pano, post-doc ku IST Austria ndi wogwira ntchito ku Dipatimenti ya Computer Technologies ku ITMO University. Imachita kafukufuku pankhani yamalingaliro ndi machitidwe amipikisano yama data. Asanagwire ntchito ku IST, adalandira PhD yake kuchokera ku yunivesite ya Paris Diderot ndi yunivesite ya ITMO moyang'aniridwa ndi Pulofesa Peter Kuznetsov.

Alexey Fedorov - Wopanga ku JUG Ru Group, kampani yaku Russia yomwe imakonza misonkhano ya otukula. Alexey adatenga nawo gawo pokonzekera misonkhano yopitilira 50, ndipo kuyambiranso kwake kumaphatikizapo chilichonse kuchokera paudindo wa injiniya wachitukuko ku Oracle (JCK, Java Platform Group) mpaka kukhala wopanga ku Odnoklassniki.

Vladimir Sitnikov -Injiniya ku Netcracker. Zaka khumi zogwira ntchito pakuchita komanso kuwopsa kwa NetCracker OS, mapulogalamu omwe amagwiritsidwa ntchito ndi oyendetsa ma telecom kuti azitha kuyendetsa makina ndi zida zogwirira ntchito. Ndimakonda zochitika za Java ndi Oracle Database. Wolemba zakusintha kopitilira khumi ndi awiri mu woyendetsa wovomerezeka wa PostgreSQL JDBC.

Kulumikizana pakati pa maphunziro ndi mafakitale

Alexey: Maurice, wagwira ntchito m'malo ophunzirira kwa nthawi yayitali kwambiri ndipo funso loyamba ndikulumikizana pakati pa maphunziro ndi mafakitale. Kodi mungalankhule za momwe kuyanjana pakati pawo kwasinthira posachedwa? Nchiyani chinachitika zaka 20-30 zapitazo ndipo nchiyani chikuchitika tsopano? 

A Maurice: Ndakhala ndikuyesetsa kugwirira ntchito limodzi ndi makampani a zamalonda chifukwa ali ndi mavuto ochititsa chidwi. Iwo, monga lamulo, sakhala ndi chidwi kwambiri mwina kufalitsa zotsatira zawo kapena kufotokozera mwatsatanetsatane mavuto awo ku gulu la dziko. Amangofuna kuthetsa mavutowa. Ndinagwira ntchito kumakampani oterowo kwakanthawi. Ndinakhala zaka zisanu ndikugwira ntchito nthawi zonse mu labotale yofufuza pa Digital Equipment Corporation, yomwe kale inali kampani yayikulu yamakompyuta. Ndinkagwira ntchito tsiku limodzi pa sabata ku Sun, ku Microsoft, ku Oracle, ndikugwira ntchito pang'ono pa Facebook. Tsopano ndikupita kutchuthi cha sabata (pulofesa wa ku yunivesite ya ku America amaloledwa kutenga tchuthi chotere kwa chaka pafupifupi kamodzi zaka zisanu ndi chimodzi zilizonse) ndikugwira ntchito Algorand, iyi ndi kampani ya cryptocurrency ku Boston. Kugwira ntchito limodzi ndi makampani kwakhala kosangalatsa nthawi zonse chifukwa ndi momwe mumaphunzirira zatsopano komanso zosangalatsa. Mutha kukhala munthu woyamba kapena wachiwiri kufalitsa nkhani pamutu womwe wasankhidwa, m'malo mongoyesetsa kukonza njira zothetsera mavuto omwe wina aliyense akukonza kale.

Alexey: Kodi mungatiuze mwatsatanetsatane momwe izi zimachitikira?

A Patrick: N’zoona. Mukudziwa, pamene ndinkagwira ntchito ku Digital Equipment Corporation, ine ndi Elliot Moss, tinapanga zokumbukira zamalonda. Inali nthawi yobala zipatso kwambiri pamene aliyense anayamba kukhala ndi chidwi ndi zamakono zamakono. Kufanana, kuphatikizapo, ngakhale machitidwe amitundu yambiri analibe. M'masiku a Dzuwa ndi Oracle, ndidagwira ntchito zambiri pazofananira zama data. Pa Facebook ndinagwira ntchito yawo blockchain, zomwe sindingathe kuziyankhula, koma ndikuyembekeza kuti zidzaonekera poyera posachedwa. Chaka chamawa, ku Algorand, ndidzakhala ndikugwira ntchito mu gulu lofufuza lomwe likuphunzira makontrakitala anzeru.

Alexey: Blockchain yakhala mutu wotchuka kwambiri m'zaka zingapo zapitazi. Kodi izi zikuthandizani kufufuza kwanu? Mwina zipangitsa kuti zikhale zosavuta kupeza thandizo kapena kupereka mwayi wopeza zinthu kuchokera kumakampani omwe akugwira ntchito m'makampaniwa?

Maurice: Ndinalandira kale ndalama zochepa kuchokera ku Ethereum Foundation. Kutchuka kwa blockchain ndikothandiza kwambiri polimbikitsa ophunzira kuti agwire ntchito imeneyi. Amachita chidwi kwambiri ndi izi ndipo amasangalala kutenga nawo mbali, koma nthawi zina samazindikira kuti kufufuza komwe kumamveka kosangalatsa kunja kumakhala kugwira ntchito mwakhama. Komabe, ndine wokondwa kwambiri kugwiritsa ntchito mystique yonse kuzungulira blockchain kuthandiza kukopa ophunzira. 

Koma si zokhazo. Ndili pagulu la alangizi la oyambitsa angapo a blockchain. Ena atha kuchita bwino, ena sangapambane, koma nthawi zonse zimakhala zosangalatsa kuwona malingaliro awo, kuwaphunzira ndikulangiza anthu. Chosangalatsa kwambiri ndi pamene mumachenjeza anthu kuti asachite zinazake. Zinthu zambiri zimaoneka ngati zabwino poyamba, koma kodi zilidi choncho?

Foundation for Blockchain Research

Vitaly: Anthu ena amaganiza kuti tsogolo lili ndi blockchain ndi ma algorithms ake. Ndipo anthu ena amati ndi kuwira kwina. Kodi munganene maganizo anu pankhaniyi?

A Maurice: Zambiri zomwe zikuchitika m’dziko la blockchain n’zolakwika, zina ndi zachinyengo, zambiri zimanyanyira. Komabe, ndikuganiza kuti pali maziko olimba asayansi a maphunzirowa. Mfundo yakuti dziko la blockchain liri lodzaza ndi kusiyana kwa malingaliro limasonyeza mlingo wa chisangalalo ndi kudzipereka. Kumbali inayi, izi sizothandiza makamaka pakufufuza kwasayansi. Tsopano, ngati mutasindikiza nkhani yomwe ikukamba za zolakwika za aligorivimu inayake, zotsatira zake sizikhala zasayansi nthawi zonse. Nthawi zambiri anthu amataya malingaliro awo. Ndikuganiza kuti chisangalalo chamtunduwu m'derali chikhoza kuwoneka chokongola kwa ena, koma kumapeto kwa tsiku, pali nkhani zenizeni za sayansi ndi zamakono zomwe ziyenera kuthetsedwa. Pali zambiri za Computer Science pano.

Vitaly: Ndiye mukuyesera kuyala maziko a kafukufuku wa blockchain, sichoncho?

A Maurice: Ndikuyesera kuyala maziko olimba, mwasayansi ndi masamu. Ndipo mbali ina ya vuto ndi yakuti nthawi zina mumayenera kutsutsa ena mwamakhalidwe okhwima a anthu ena ndikunyalanyaza. Nthawi zina anthu amandifunsa chifukwa chimene ndimagwirira ntchito kudera limene kuli zigawenga komanso anthu ozembetsa mankhwala osokoneza bongo. Kuchita koteroko n'kopanda tanthauzo ngati khalidwe la otsatira omwe amabwereza mawu anu mwachimbulimbuli. Ndikuganiza kuti chowonadi chiri penapake pakati. Blockchain idzakhudza kwambiri anthu komanso chuma cha padziko lonse. Koma izi mwina sizichitika chifukwa chaukadaulo wamakono. Tekinoloje zamakono zidzakula ndipo zomwe zidzatchedwa blockchain m'tsogolomu zidzakhala zofunika kwambiri. Izo sizingawoneke ngati blockchains amakono, ndilo funso lotseguka.

Ngati anthu apanga matekinoloje atsopano, apitiliza kuyitcha blockchain. Ndikutanthauza, monga Fortran yamasiku ano ilibe chochita ndi chilankhulo cha Fortran kuyambira m'ma 1960, koma aliyense amachitcha kuti Fortran. Zomwezo kwa UNIX. Zomwe zimatchedwa "blockchain" zidzasinthabe. Koma ndikukayika kuti blockchain yatsopanoyi ikhala ngati zomwe aliyense amakonda kugwiritsa ntchito lero.

Kodi malingaliro opambana amachokera kuti? Zotsatira za kutchuka

Alexey: Kodi kutchuka kwa blockchain kwadzetsa zotsatira zatsopano kuchokera kumalingaliro asayansi? Kuyanjana kwambiri, ophunzira ambiri, makampani ambiri m'deralo. Kodi pali kale zotsatira za kutchuka kumeneku?

A Maurice: Ndinachita chidwi ndi zimenezi munthu wina atandipatsa kapepala ka kampani ina imene inali itangopeza ndalama zambiri. Ilo linalemba za ntchito ya akuluakulu a Byzantine, zomwe ndimazidziwa bwino kwambiri. Zomwe zidalembedwa mu kapepalaka zinali zolakwika mwaukadaulo. Anthu omwe adalemba zonsezi sanamvetse bwino chitsanzo cha vutoli ... ndipo komabe kampaniyi inapeza ndalama zambiri. Pambuyo pake, kampaniyo inasintha mwakachetechete kapepala kameneka ndi mtundu wolondola kwambiri - ndipo sindinena kuti dzina la kampaniyi linali liti. Adakalipo ndipo akuchita bwino kwambiri. Chochitikachi chinanditsimikizira kuti, choyamba, blockchain ndi mtundu wa makompyuta omwe amagawidwa. Kachiwiri, malo olowera (osachepera pamenepo, zaka zinayi zapitazo) anali otsika kwambiri. Anthu amene ankagwira ntchito imeneyi anali amphamvu komanso anzeru, koma sankawerenga mapepala a sayansi. Iwo anayesa kuyambitsanso zinthu zodziwika ndipo analakwitsa. Masiku ano sewero lachepa.

Alexey: Izi ndizosangalatsa kwambiri, chifukwa zaka zingapo zapitazo tinali ndi chikhalidwe chosiyana. Zili ngati chitukuko chakumapeto, pamene opanga osatsegula akutsogolo adayambitsanso matekinoloje onse omwe anali odziwika kale kumapeto: kumanga machitidwe, kuphatikiza kosalekeza, zinthu monga choncho. 

A Patrick: Ndikuvomereza. Koma izi sizodabwitsa, chifukwa malingaliro opambana enieni nthawi zonse amachokera kunja kwa anthu okhazikika. Ofufuza okhazikika, makamaka ophunzira okhazikika, sangakane kuchita chilichonse chokhumudwitsa. Ndikosavuta kulemba pepala la msonkhano wotsatira wa momwe munasinthira pang'ono zotsatira za ntchito yanu yakale. Pitani kumsonkhano, khalani pamodzi ndi anzanu, kambiranani zinthu zomwezo. Ndipo anthu omwe amabwera ndi malingaliro opambana pafupifupi nthawi zonse amachokera kunja. Iwo sadziwa malamulo, sadziwa chinenero, koma komabe ... Ngati muli m'dera lokhazikitsidwa, ndikukulangizani kuti mumvetsere zinthu zatsopano, zomwe sizikugwirizana ndi chithunzi chonse. M'lingaliro lina, kuyesa kungapangidwe kugwirizanitsa zochitika zakunja, zowonjezereka zamadzimadzi ndi njira zomwe timamvetsetsa kale. Monga sitepe yoyamba, yesani kukhazikitsa maziko asayansi, ndiyeno muwasinthe kuti agwiritsidwe ntchito pamalingaliro atsopano opambana. Ndikuganiza kuti blockchain ndiyabwino kukhala lingaliro latsopano, losokoneza.

Alexey: Kodi mukuganiza kuti chifukwa chiyani izi zimachitika? Chifukwa anthu "akunja" alibe zopinga zilizonse zomwe zimachitika m'deralo?

A Patrick: Pali zinthu zina zimene zikuchitika apa. Ngati muwerenga mbiri ya impressionists mu kujambula ndi luso ambiri, ndiye nthawi ina ojambula otchuka anakana impressionism. Iwo ankati zinali ngati zachibwana. M'badwo pambuyo pake, zojambulajambula zomwe zidakanidwa kalezi zidakhala muyezo. Zomwe ndikuwona m'munda wanga: oyambitsa blockchain analibe chidwi ndi mphamvu, pakuwonjezera zofalitsa ndi index yotsatsira, amangofuna kuchita zabwino. Ndipo kotero iwo anakhala pansi nayamba kuchita izo. Iwo analibe kuchuluka kwa kuya kwaukadaulo, koma ndizotheka. Ndizovuta kwambiri kupeza malingaliro atsopano opangira kusiyana ndi kukonza ndi kulimbikitsa osakhwima mokwanira. Chifukwa cha oyambitsawa, tsopano ndili ndi chochita!

Alexey: Izi zikufanana ndi kusiyana pakati pa oyambitsa ndi ntchito zolowa. Timatengera zofooka zambiri za kuganiza, zotchinga, zofunika zapadera, ndi zina zotero.

Maurice: Fanizo labwino limagawidwa pakompyuta. Ganizirani za blockchain ngati kuti inali yoyambira ndikugawa makompyuta ngati kampani yayikulu, yokhazikika. Makompyuta ogawidwa ali m'kati mwa kupezedwa ndikuphatikizidwa ndi blockchain.

PhD moyang'aniridwa ndi Barbara Liskov

Vitaly: Tili ndi mafunso ambiri! Tinkayang'ana mbiri yanu ndipo tidapeza mfundo yosangalatsa yokhudza udokotala wanu. Inde, izi zinali kalekale, koma zikuwoneka kuti ndi mutu wofunikira. Munalandira PhD yanu motsogozedwa ndi inu nokha Barbara Liskov! Barbara amadziwika bwino m'gulu la zilankhulo zamapulogalamu, komanso munthu wodziwika bwino kwambiri. Ndizomveka kuti kafukufuku wanu anali wokhudza zilankhulo zamapulogalamu. Munasinthira bwanji kukhala parallel computing? Chifukwa chiyani mwaganiza zosintha mutu?

A Maurice: Pa nthawiyo, Barbara ndi gulu lake ankangoyang’ana pa kompyuta yogawira anthu, lomwe linali lingaliro latsopano kwambiri. Panalinso ena amene ankati makompyuta ogawira ena n’zachabechabe komanso kuti makompyuta amene amalankhulana wina ndi mnzake n’ngopanda pake. Chimodzi mwazinthu zomwe zimayankhidwa pamakompyuta ogawidwa omwe amasiyanitsa ndi makompyuta apakati ndi kulekerera zolakwika. Pambuyo pofufuza zambiri, tidaganiza kuti chilankhulo chogawidwa chapakompyuta chiyenera kukhala ndi zina ngati ma atomiki chifukwa simungatsimikize kuti kuyimba kwakutali kudzapambana. Mukakhala ndi zochitika, vuto la kasamalidwe ka ndalama limayamba. Ndiye panali ntchito yambiri yopezera ma data ogwirizana kwambiri. Kenako, nditamaliza maphunziro, ndinapita Carnegie Mellon ndikuyamba kufunafuna mutu woti tigwirepo. Zinandidabwitsa kuti makompyuta achoka pamakompyuta amodzi kupita ku netiweki yamakompyuta. Multiprocessors angakhale kupitiriza kwachilengedwe kwa kupita patsogolo - mawu oti "multi-core" anali asanakhalepo. Ndinaganiza: ndi chiyani chomwe chikufanana ndi ma atomiki amtundu wamitundu yambiri? Zowona, osati zochitika zanthawi zonse chifukwa ndizokulirapo komanso zolemetsa. Ndipo umo ndi momwe ndinapezera lingaliro linearizability ndipo ndimomwe ndidabwera ndi kulunzanitsa kopanda kudikirira konse. Uku kunali kuyesa kuyankha funso loti analogue ya ma atomiki amtundu wa ma multiprocessor omwe amagawana nawo ndi chiyani. Poyang'ana koyamba, ntchitoyi ikhoza kuwoneka yosiyana kwambiri, koma kwenikweni ndikupitilira mutu womwewo.

Dziko likuyembekezera multi-core

Vitaly: Munanena kuti panthawiyo kunali makompyuta ochepa kwambiri, sichoncho?

A Patrick: Iwo kunalibe. Panali angapo otchedwa symmetric multiprocessors, omwe anali olumikizidwa ku basi yomweyo. Izi sizinagwire ntchito bwino chifukwa nthawi iliyonse kampani yatsopano ikapanga zofanana, Intel imamasula purosesa imodzi yomwe inali yabwino kuposa ma multiprocessor.

Alexey: Kodi izi sizikutanthauza kuti m'nthawi zakalezo zinali zongopeka chabe?

Maurice: Sinali phunziro longopeka chabe, koma longopeka chabe. Zonsezi sizinali zogwira ntchito ndi malingaliro ambiri; m'malo mwake, tinkapereka malingaliro okhudza zomangamanga zomwe kunalibe panthawiyo. Izi ndi zomwe kafukufuku ali nazo! Palibe kampani yomwe ikadachita izi; zonse zinali zamtsogolo. M'malo mwake, izi zinali choncho mpaka 2004, pomwe mapurosesa enieni amitundu yambiri adawonekera. Chifukwa mapurosesa amatenthedwa kwambiri, mutha kupanga purosesa kukhala yaying'ono, koma simungathe kuyipanga mwachangu. Chifukwa cha izi, panali kusintha kwa zomangamanga zambiri. Ndipo izi zikutanthauza kuti mwadzidzidzi panali kugwiritsidwa ntchito kwa malingaliro onse omwe tidapanga m'mbuyomu.

Alexey: Kodi mukuganiza kuti chifukwa chiyani mapurosesa amitundu yambiri adawonekera m'ma XNUMX okha? Nanga n’cifukwa ciani kwachedwa?

A Maurice: Izi zimachitika chifukwa cha kuchepa kwa zida zamagetsi. Intel, AMD ndi makampani ena ndiabwino kwambiri pakuwonjezera liwiro la purosesa. Pamene nthawi zina mapurosesa anakhala ang'onoang'ono moti sakanathanso kuonjezera liwiro la wotchi chifukwa mapurosesa angayambe kuyaka. Mutha kuwapanga kukhala ochepa, koma osati mwachangu. Zomwe zili mu mphamvu zawo - m'malo mwa purosesa yaying'ono kwambiri, imatha kukwanira mapurosesa asanu ndi atatu, khumi ndi zisanu ndi chimodzi kapena makumi atatu ndi awiri mu voliyumu yomweyi yamilandu, pomwe m'mbuyomu ndi imodzi yokha. Tsopano muli ndi ma multithreading komanso kulumikizana mwachangu pakati pawo chifukwa amagawana ma cache. Koma simungawakakamize kuthamanga - pali malire enieni a liwiro. Iwo akupitirizabe kusintha pang'onopang'ono, koma osati kwambiri. Malamulo a fizikiya adayima m'njira yopita patsogolo.

Dziko latsopano limabweretsa mavuto atsopano. NUMA, NVM ndi kuwononga zomangamanga

Alexey: Zikumveka zomveka. Ndi mapurosesa atsopano amitundu yambiri adabwera ndi mavuto atsopano. Kodi inu ndi anzanu mumayembekezera mavutowa? Mwina munaphunzira nawo pasadakhale? M'maphunziro aukadaulo nthawi zambiri sikophweka kulosera zinthu zotere. Pamene mavuto adachitika, adakwaniritsa bwanji zomwe mukuyembekezera komanso anzanu? Kapena kodi anali atsopano, ndipo inu ndi anzanu munayenera kuthera nthawi yochuluka kuthetsa mavuto momwe amawonekera?

Vitaly: Ndiwonjezera ku funso la Alexey: kodi mudaneneratu molondola za zomangamanga pamene mukuphunzira chiphunzitsocho?

Maurice: Osati 100%. Koma ndikuganiza anzanga ndi ine tachita ntchito yabwino kulosera ma cores ambiri omwe amagawana nawo kukumbukira. Ndikuganiza kuti tidaneneratu molondola za zovuta kupanga ma data ofanana omwe amagwira ntchito popanda maloko. Mapangidwe amtundu woterewa akhala ofunikira pamapulogalamu ambiri, ngakhale si onse, koma nthawi zambiri zomwe mumafunikira ndizosatsekeka. Pamene tinkawatulukira, ambiri ankanena kuti zimenezi n’zachabechabe, kuti zonse zinkayenda bwino ndi maloko. Tidaneneratu bwino lomwe kuti pakhala njira zokonzekera zovuta zamapulogalamu ambiri komanso zovuta zamadongosolo a data. Panalinso mavuto ovuta kwambiri, monga NUM - mwayi wosagwirizana ndi kukumbukira. M'malo mwake, sanaganizidwe mpaka ma processor amitundu yambiri atapangidwa chifukwa anali achindunji kwambiri. Gulu lofufuza likugwira ntchito pa mafunso omwe nthawi zambiri anali odziwika bwino. Mavuto ena a hardware okhudzana ndi zomangamanga zinayenera kudikirira m'mapiko - makamaka, maonekedwe a zomangamanga. Mwachitsanzo, palibe amene adagwirapo ntchito pamakina amtundu wa GPU chifukwa ma GPU kunalibe kalelo. Ngakhale ntchito zambiri zachitika SIMD, ma aligorivimuwa anali okonzeka kugwiritsidwa ntchito mwamsanga zida zoyenera zitapezeka. Komabe, n’zosatheka kudziwiratu zonse.

Alexey: Ngati ndimvetsetsa bwino, NUMA ndi mtundu wonyengerera pakati pa mtengo, magwiridwe antchito ndi zinthu zina. Pali malingaliro aliwonse chifukwa chiyani NUMA idatuluka mochedwa chonchi?

Maurice: Ndikuganiza kuti NUMA ilipo chifukwa cha zovuta ndi zida zomwe zimagwiritsidwa ntchito popanga kukumbukira: mbali zomwe zili kutali kwambiri, zimachedwa kuzifikira. Kumbali ina, phindu lachiwiri lachidziwitso ichi ndi kukumbukira kukumbukira. Chifukwa chake chimodzi mwazinthu zama komputa yofananira ndikuti zotsalira zonse zimasweka pang'ono. Ngati kulowa kunali kofanana bwino, kukumbukira konse kukanakhala kofanana, koma izi ndi zachuma, ndipo mwinamwake ngakhale mwakuthupi, zosatheka. Chifukwa chake mkangano uwu umabuka. Ngati mulemba pulogalamu yanu ngati kuti kukumbukira ndi yunifolomu, ndiye kuti idzakhala yolondola. M’lingaliro lakuti sichidzapereka mayankho olakwika. Koma machitidwe ake sangagwirenso nyenyezi kuchokera kumwamba. Momwemonso, ngati mulemba spinlocks Popanda kumvetsetsa utsogoleri wa cache, kudziletsa komweko kudzakhala kolondola, koma mutha kuyiwala za magwiridwe antchito. Mwanjira ina, muyenera kulemba mapulogalamu omwe amakhala pamwamba pazosavuta, koma muyenera kupitilira anthu omwe adakupatsani chidziwitsocho: muyenera kudziwa kuti pansi pazidziwitso pali gulu lina la kukumbukira, kuti pali basi pakati panu ndi kukumbukira uku, ndi zina zotero. Chifukwa chake, pali mkangano wina pakati pa zongopeka za aliyense payekhapayekha, zomwe zimatifikitsa ku zovuta zenizeni komanso za pragmatic.

Vitaly: Nanga m’tsogolo? Kodi mungadziwiretu momwe mapurosesa adzapangire pambuyo pake? Pali lingaliro lakuti imodzi mwamayankho ndi kukumbukira zochitika. Mwina muli ndi china chake m'sitolo.

A Maurice: Pali mavuto aakulu angapo m’tsogolo. Chimodzi ndi chakuti kukumbukira kogwirizana ndi chinthu chodabwitsa, koma kumayamba kuwonongeka muzochitika zapadera. Kotero, mwachitsanzo, NUMA ndi chitsanzo chamoyo cha chinachake chomwe mungapitirize kuyerekezera kuti kukumbukira kofanana kulipo. Kwenikweni ayi, zokolola zimakupangitsani kulira. Panthawi ina, omanga mapulani adzayenera kusiya lingaliro la kamangidwe ka kukumbukira kamodzi; simungathe kunamizira kwamuyaya. Mitundu yatsopano yamapulogalamu idzafunika yosavuta kugwiritsa ntchito komanso yamphamvu kwambiri kuti zida zoyambira zikhale zogwira mtima. Izi ndizovuta kwambiri, chifukwa ngati muwonetsa olemba mapulogalamu zomangamanga zomwe zimagwiritsidwa ntchito mu hardware, iwo adzapenga. Ndizovuta komanso zosasunthika. Ngati mupereka mawonekedwe omwe ali ophweka kwambiri, ntchitoyo idzakhala yosauka. Chifukwa chake, kusinthanitsa kwakukulu kovutirako kudzafunika kupangidwa kuti apereke mitundu yothandiza yamapulogalamu yomwe imagwira ntchito kwa mapurosesa akuluakulu amitundu yambiri. Sindikutsimikiza kuti wina aliyense kupatula katswiri amatha kupanga mapulogalamu pakompyuta ya 2000-core. Ndipo pokhapokha mukuchita mwapadera kwambiri kapena sayansi yamakompyuta kapena cryptography kapena china chonga icho - sizikudziwika bwino momwe mungachitire molondola. 

Malo ena ofanana ndi a zomangamanga zapadera. Ma graph accelerators akhalapo kwa nthawi yayitali, koma akhala ngati chitsanzo cha momwe mungatengere mtundu wapadera wa makompyuta ndikuyendetsa pa chip chodzipatulira. Izi zimawonjezera zovuta zake: momwe mumalankhulirana ndi chipangizo choterocho, momwe mumachikonzera. Posachedwapa ndakhala ndikugwira ntchito yothetsa mavuto m'derali pafupi ndi kukumbukira makompyuta. Mumatenga purosesa yaying'ono ndikuyimatira ku kukumbukira kwakukulu kotero kuti kukumbukira kumathamanga pa liwiro la cache la L1 ndikulumikizana ndi chipangizo ngati. TPU - purosesa ili kalikiliki kukweza ntchito zatsopano m'makumbukidwe anu. Kupanga mapangidwe a data ndi njira zoyankhulirana zamtunduwu ndi chitsanzo china chosangalatsa. Chifukwa chake mapurosesa achikhalidwe ndi ma Hardware apitiliza kuwona kusintha kwakanthawi.

Alexey: Nanga bwanji kukumbukira kosasinthika (kukumbukira kosasinthika)?

A Patrick: Chimenechi ndi chitsanzo china chabwino kwambiri. NVM idzasintha kwambiri momwe timawonera zinthu monga ma data. Kukumbukira kosasinthika, mwanjira ina, kumalonjeza kufulumizitsa zinthu. Koma sizipangitsa moyo kukhala wosavuta chifukwa mapurosesa ambiri, ma cache, ndi zolembetsa zikadali zosasinthika. Mukangoyamba kuwonongeka, malo anu ndi kukumbukira kwanu sizidzakhala chimodzimodzi ndi ngozi isanachitike. Ndine woyamikira kwambiri kwa anthu omwe akugwira ntchito pa NVM - padzakhala zambiri zoti ochita kafukufuku azichita kwa nthawi yaitali poyesa kupeza zolondola. Kuwerengera ndi kolondola ngati atha kupulumuka ngozi yomwe zomwe zili mu cache ndi zolembetsa zimatayika, koma kukumbukira kwakukulu kumakhalabebe.

Compilers vs processors, RISC vs CISC, kugawana kukumbukira vs kudutsa uthenga

Vladimir: Mukuganiza bwanji za vuto la "compilers vs. processors" kuchokera pamawonedwe a malangizo? Ndiroleni ndifotokozere kwa omwe sakudziwa: ngati tipita ku kukumbukira kolakwika kapena zina zofananira, titha kugwiritsa ntchito malamulo osavuta ndikufunsa wopangayo kuti apange ma code ovuta omwe angagwiritse ntchito mwayi watsopano. Kapena titha kupita njira ina: tsatirani malangizo ovuta ndikufunsa purosesa kuti akonzenso malangizowo ndikuchita nawo zinthu zina. Mukuganiza bwanji pa izi?

A Patrick: Ndilibe yankho la funso limeneli. Mtsutso uwu wakhala ukupitirira kwa zaka makumi anayi. Panali nthawi yomwe pakati chidule gulu la malamulo ndi zovuta Nkhondo zapachiŵeniŵeni zinkachitika potsatira malamulo angapo. Kwa kanthawi, anthu a RISC adapambana, koma Intel adamanganso injini zawo kuti malangizo ochepetsera agwiritsidwe ntchito mkati, ndipo seti yonse idatumizidwa kunja. Uwu mwina ndi mutu womwe m'badwo watsopano uliwonse uyenera kupeza zomwe wagwirizana ndikudzipangira zisankho. Ndizovuta kwambiri kuneneratu kuti ndi zinthu ziti zomwe zingakhale zabwinoko. Chifukwa chake kulosera kulikonse komwe ndingapange kudzakhala kowona kwa nthawi inayake, ndiyeno zabodzanso kwakanthawi, kenako ndizoonanso.

Alexey: Kodi ndizofala bwanji pamakampani omwe malingaliro ena amapambana kwazaka makumi angapo ndikutaya pambuyo pake? Kodi pali zitsanzo zina za kusintha kwa nthawi ndi nthawi?

A Maurice: Pankhani yogawira makompyuta, pali anthu amene amakhulupirira adagawana kukumbukira ndi anthu amene amakhulupirira mauthenga. Poyamba, mu computing yogawidwa, parallel computing imatanthauza kudutsa uthenga. Kenako wina adapeza kuti kunali kosavuta kupanga ndi kukumbukira komwe kugawana. Mbali inayi inanena kuti kukumbukira komwe kugawanako kumakhala kovuta kwambiri, chifukwa kumafunika maloko ndi zina zotero, choncho ndi bwino kusamukira kuzilankhulo zomwe palibe chilichonse koma uthenga wongodutsa. Wina adayang'ana zomwe zidatuluka mu izi ndikuti, "wow, kukhazikitsidwa kwa mauthenga uku kumawoneka ngati kukumbukira komwe kugawana, chifukwa mumapanga ma module ambiri, amatumizirana mauthenga, ndipo onse interlock"Tiyeni tipange nkhokwe yamakumbukiro yogawana bwino!" Zonsezi zikubwerezedwa mobwerezabwereza, ndipo sizingatheke kunena kuti imodzi mwa maphwando ndi yolondola. Imodzi mwa mbaliyi idzalamulira nthawi zonse chifukwa imodzi mwa izo ikangotsala pang'ono kupambana, anthu mobwerezabwereza amapanga njira zowonjezeramo.

Luso Lolemba Brittle Multithreaded Code

Alexey: Izi ndizosangalatsa kwambiri. Mwachitsanzo, tikamalemba ma code, mosasamala kanthu za chinenero cha pulogalamu, nthawi zambiri timafunika kupanga zotsalira monga maselo omwe amatha kuwerenga ndi kulembedwa. Koma kwenikweni, pamlingo wina, izi zitha kuwoneka ngati kutumiza uthenga pabasi ya hardware pakati pa makompyuta osiyanasiyana ndi zida zina. Zikuoneka kuti ntchito ikuchitika pa magawo onse awiri nthawi imodzi.

A Maurice: Ndizowona kuti kukumbukira komwe kugawana kumapangidwa ndi mauthenga - mabasi, ma cache, ndi zina zotero. Koma ndizovuta kulemba mapulogalamu pogwiritsa ntchito uthenga wodutsa, kotero hardware imanama mwadala, kumayesa kuti muli ndi mtundu wina wa kukumbukira yunifolomu. Izi zidzakupangitsani kukhala kosavuta kuti mulembe mapulogalamu osavuta, olondola ntchito isanayambe kuwonongeka. Ndiye mudzati: zikuwoneka kuti ndi nthawi yoti mupange mabwenzi ndi cache. Ndiyeno mumayamba kudandaula za malo a cache, ndipo kuchokera pamenepo amapita. Mwanjira ina, mukubera zomwe zatchulidwazi: mukudziwa kuti sizongokumbukira zokhazokha, ndipo mugwiritsa ntchito chidziwitsochi kulemba mapulogalamu ochezeka. Izi ndi zomwe muyenera kuchita pamavuto enieni. Mkanganowu pakati pa zotsekemera, zosavuta, zabwino zomwe mwapatsidwa komanso kukhazikitsidwa kovutirapo kwa zida zoyambira ndipamene aliyense adzipangira yekha. Ndili ndi bukhu lonena za ma multiprocessors ndi ma synchronization, ndipo nthawi ina ndimati ndilembe mutu pazapangidwe za data mu java.util.concurrent. Ngati muyang'ana pa iwo, zinthu monga mindandanda yokhala ndi zosiyidwa Izi ndi ntchito zodabwitsa zaluso. (Zolemba mkonzi: Amene amadziwa chinenero cha Java ayenera kuyang'ana momwe akugwiritsira ntchito ConcurrentSkipListMap, mukhoza kuyang'ana pa maulalo API и source kodi). Koma kuchokera kumalingaliro anga, sikungakhale kusasamala kuwawonetsa kwa ophunzira, chifukwa mawonekedwe a data otere amakhala ngati munthu wamasewera othamanga pazingwe zolimba pamwamba pa dzenje la zimbalangondo. Ngati musintha ngakhale pang'ono pang'ono, dongosolo lonselo lidzagwa. Khodi iyi ndi yachangu komanso yokongola chifukwa idalembedwa mwangwiro, koma kusintha pang'ono kumabweretsa kulephera kwathunthu. Ndikapereka kachidindo kameneka monga chitsanzo kwa ophunzira, nthawi yomweyo anena kuti: Inenso ndikhoza kutero! Ndiyeno ndege ina idzagwa kapena choyatsira nyukiliya chidzaphulika, ndipo ndidzakhala wolakwa powapatsa chidziwitso chochuluka pa nthawi yolakwika.

Alexey: Ndili wamng'ono, nthawi zambiri ndinkayesera kuphunzira kachidindo ka Doug Lee, mwachitsanzo, java.util.concurrent, chifukwa ndi gwero lotseguka, ndizosavuta kupeza ndikuyesera kumvetsetsa zomwe zikuchitika kumeneko. Sizinakhale bwino: nthawi zambiri, sizikudziwika bwino chifukwa chake Doug adaganiza zochita izi pomwe wina aliyense akuchita mosiyana. Kodi mumafotokozera bwanji zinthu zimenezi kwa ophunzira anu? Kodi pali njira yolondola yofotokozera zambiri za hardcore algorithm, mwachitsanzo? Kodi mumachita bwanji izi?

Maurice: Aphunzitsi ojambula ali ndi cliché yomwe amakumbukira poyamba: ngati mukufuna kujambula ngati Picasso, choyamba muyenera kuphunzira momwe mungajambulire zithunzi zosavuta zenizeni, ndipo pokhapokha mutadziwa malamulo omwe mungayambe kuwaphwanya. Ngati mutayamba kuswa malamulo nthawi yomweyo, mumangowonongeka. Choyamba, ndimaphunzitsa ophunzira momwe angalembe zilembo zosavuta, zolondola popanda kudandaula za momwe angagwiritsire ntchito. Zomwe ndikunena ndikuti, pali zovuta zanthawi yayitali pano, chifukwa chake musade nkhawa ndi ma cache, musadandaule zamitundu yokumbukira, ingowonetsetsa kuti zonse zikuyenda bwino. Izi ndizovuta kale: mapulogalamu amakono siwophweka paokha, makamaka kwa ophunzira atsopano. Ndipo akakhala ndi chidziwitso cha momwe angalembere mapulogalamu abwino, ndimati: yang'anani machitidwe awiriwa a spinlock: imodzi imachedwa kwambiri, ndipo yachiwiri siili bwino, koma yabwino. Komabe, masamu ma aligorivimu awiriwa ndi ofanana. M'malo mwake, m'modzi waiwo amagwiritsa ntchito malo a cache. Imodzi imagwira ntchito pazida zomwe zasungidwa komweko, ndipo inayo imagwira ntchito m'basi mobwerezabwereza. Simungathe kulemba kachidindo koyenera ngati simukumvetsa kuti ndi chiyani, ndipo simukudziwa momwe mungachotsere zotsalirazo ndikuyang'ana zomwe zili pansi pake. Koma simungathe kuyamba kuchita izi nthawi yomweyo. Pali anthu omwe amayamba kuchita izi nthawi yomweyo ndikukhulupirira mwanzeru zawo, nthawi zambiri zimatha moyipa chifukwa samamvetsetsa mfundo zake. Palibe amene amajambula ngati Picasso kapena amalemba mapulogalamu ngati Doug Lee atangotuluka kumene ku koleji sabata yake yoyamba. Zimatenga zaka zambiri kuti munthu adziwe zambiri.

Alexey: Zikuwonekeratu kuti mumagawanitsa vutoli m'magawo awiri: choyamba ndi cholondola, chachiwiri ndi ntchito?

A Maurice: N’zoonadi. Ndipo, ndendende mu dongosolo limenelo. Chimodzi mwavuto ndi chakuti ophunzira atsopano samamvetsetsa kuti kulondola ndi kovuta kukwaniritsa. Poyang'ana koyamba amati: izi ndizolondola, zomwe zatsala ndikufulumizitsa. Chifukwa chake nthawi zina ndimawauza za algorithm yolakwika poyamba ngati kuti inali yolondola.

Momwe mungaphunzitsire ophunzira kulemba ma code ovuta a multithreaded

Alexey: Kungowona ngati atha kuzindikira?

A Maurice: Nthawi zonse ndimachenjeza pasadakhale kuti nthawi zina ndimapanga malingaliro olakwika. Musamanamize anthu. Ine amati atenge zambiri ndi njere yamchere. Ngati ndikunena chinachake ndikunena kuti: "Tawonani, izi ndi zolondola" - ichi ndi chizindikiro chakuti kwinakwake akuyesera kukunyengererani, ndipo muyenera kuyamba kufunsa mafunso. Kenako, ndimayesetsa kulimbikitsa ophunzira kuti azifunsabe mafunso, kenako ndimawauza kuti, “Kodi chingachitike n’chiyani ngati tisiya zinthu mmene zilili?” Ndipo nthawi yomweyo amawona kulakwitsa. Koma kutsimikizira ophunzira kuti akuyenera kuda nkhawa ndi kulondola ndikovuta kwambiri kuposa momwe zimawonekera poyang'ana koyamba. Ambiri mwa ophunzirawa amabwera ndi zochitika zamapulogalamu kusukulu yasekondale, ena apeza ntchito ndipo apanga mapulogalamu kumeneko, ndipo onse ali ndi chidaliro. Izi ndizofanana ndi ankhondo: choyamba muyenera kusintha malingaliro awo kuti muwatsimikizire kuti ayandikira kuthetsa mavuto omwe amabwera. Kapena mwina zili ngati amonke achi Buddha: choyamba amaphunzira kulingalira za kulondola, ndipo akamvetsetsa njira zoganizira zolondola, amaloledwa kupita kumlingo wina ndikuyamba kuda nkhawa za momwe angagwiritsire ntchito.

Alexey: Ndiko kuti, nthawi zina mumasonyeza ophunzira zitsanzo zosagwira ntchito, chifukwa chake mumalandira ndemanga zosonyeza ngati akumvetsa chiyambi cha vuto, kaya angapeze code yolakwika ndi zotsatira zolakwika. Ndiye, kodi ophunzira amakupangitsani kukhala osangalala kapena achisoni?

A Maurice: Nthaŵi zambiri ana asukulu amapeza cholakwa pamapeto pake. Ngati amafufuza pang'onopang'ono, ndimafunsa mafunso otsogolera, ndipo apa ndikofunika kumvetsetsa kuti ngati simunawapusitse, adzayamba kuzindikira mopanda nzeru mawu anu ngati choonadi chenichenicho. Kenako amatopa ndikuyamba kugona akuwerenga Facebook pa laputopu yawo nthawi ya kalasi. Koma ukawauza pasadakhale kuti adzapusitsidwa, ndipo amaoneka ngati opusa ngati sazindikira chinyengo, amakhala tcheru kwambiri. Izi ndi zabwino m'njira zosiyanasiyana. Ndikufuna ophunzira kuti asamangokayikira kumvetsetsa kwawo pankhaniyi, komanso kukayikira ulamuliro wa mphunzitsi. Lingaliro ndiloti wophunzira akhoza kukweza dzanja lake nthawi iliyonse ndikunena kuti: Ndikuganiza kuti zomwe mwanenazi ndi zolakwika. Ndi chida chofunikira chophunzirira. Sindikufuna kuti wophunzira aliyense akhale pansi ndikudziganizira okha: zonsezi zikuwoneka zopanda pake, koma kukweza dzanja lanu ndikowopsya kwambiri, ndipo mulimonse, iye ndi pulofesa, kotero zonse zomwe akunena ndi zoona. Chotero, ngati achenjezedwa pasadakhale kuti si zonse zimene zanenedwa ziridi zoona, amakhala ndi chisonkhezero cha kumvetsera kwambiri nkhaniyo. Ndikuwonetsa kuti palibe vuto kukweza dzanja ndikufunsa mafunso. Funso lanu lingamveke ngati lopusa kapena lopanda nzeru, koma nthawi zambiri ndi momwe mafunso abwino amawukira.

Alexey: Zosangalatsa kwambiri. Nthawi zambiri anthu amakhala ndi chotchinga chamtundu wina chomwe sichiwalola kufunsa funso kwa pulofesa. Makamaka ngati pali anthu ambiri m'chipindamo, ndipo aliyense akuwopa kuti kukambirana funso lanu lopusa kudzatenga nthawi ya anthu onsewa. Kodi pali njira zothana ndi izi?

A Patrick: Nthawi zambiri ndimaima n’kufunsa mafunso akale. Kaya chiganizo chingakhale cholondola, kapena momwe angathetsere vuto lomwe likukambidwa. Ichi ndi chinthu chofunika kwambiri, makamaka kumayambiriro kwa phunziro pamene anthu amachita manyazi kunena ngakhale zazing'ono. Mumafunsa ophunzira funso osanenanso kanthu. Pamakhala chete, aliyense amakhala wovuta pang'ono, kukangana kumakula, ndiye mwadzidzidzi wina sangathe kupirira, amasweka ndikuyankha yankho. Umu ndi momwe mumasinthira zinthu: kupitiriza kukhala chete kumakhala kovuta komanso kovutirapo kuposa kuyankha! Ichi ndi chinyengo chokhazikika chamaphunziro. Mphunzitsi aliyense padziko lapansi ayenera kudziwa momwe angachitire izi.

Alexey: Tsopano tili ndi mutu wabwino kwambiri wofunsa mafunsowa: "ndikosavuta kuyankha kuposa kukhala chete."

Vitaly: Ndifunsenso. Mukugwira ntchito pazotsimikizira zakuthambo. Munalowa nawo bwanji mu izi, chifukwa makompyuta ogawidwa ndi topology ndi zinthu zosiyana kwambiri!

A Maurice: Pali kugwirizana kobisika kumeneko. Pamene ndinali wophunzira wa masamu, ndinaphunzira masamu opanda kanthu. Ndinalibe chidwi kwenikweni ndi makompyuta mpaka maphunziro anga anatha ndipo ndinadzipeza ndikuyang'anizana ndi kufunikira kofunafuna ntchito. Monga wophunzira ndinaphunzira algebraic topology. Patapita zaka zambiri, pamene ntchito pa vuto lotchedwa "K-Set Agreement Vuto", ndinagwiritsa ntchito ma grafu kuti ndiwonetsere vutolo ndipo, monga momwe zinkawonekera panthaŵiyo, ndinali nditapeza yankho. Inu munangoyenera kukhala pansi ndi kuzungulira kuwerengera. Yesani kupeza yankho loyenera pa graphyi. Koma algorithm yanga sinagwire ntchito: zidapezeka kuti amayenda mozungulira mpaka kalekale. Tsoka ilo, zonsezi sizikanatha kufotokozedwa m'chinenero chovomerezeka cha chiphunzitso cha graph - chomwe asayansi onse apakompyuta amadziwa. Ndiyeno ndinakumbukira kuti zaka zambiri zapitazo, mmbuyo mu makalasi a topology, timagwiritsa ntchito lingalirolo "simplicial complex", zomwe ndi kuphatikizika kwa ma graph kuti akhale apamwamba kwambiri. Kenako ndidadzifunsa kuti: chingachitike ndi chiyani ngati titakonzanso vutoli motengera zovuta zosavuta? Iyi idakhala nthawi yofunika kwambiri. Pogwiritsa ntchito mawonekedwe amphamvu kwambiri, vutoli mwadzidzidzi limakhala losavuta. Anthu adalimbana nawo kwa nthawi yayitali, pogwiritsa ntchito ma graph, koma sanathe kuchita chilichonse. Ndipo ngakhale tsopano iwo sangakhoze - yankho lolondola linakhala osati algorithm, koma umboni wa zosatheka kuthetsa vutoli. Ndiye kuti, algorithm yotereyi kulibe. Koma umboni uliwonse wosatheka zozikidwa pa zinthu zosavuta kumva kapena zinthu zimene anthu ankanamizira kuti saziganizira mophweka. Chifukwa chakuti mumatchula dzina latsopano, sichitaya tanthauzo lake.

Vitaly: Zikuoneka kuti unali ndi mwayi basi?

A Maurice: Kupatulapo mwayi, ulinso kufunitsitsa. Izi zikutanthauza kuti musaiwale zinthu "zopanda ntchito" zomwe mudaphunzira kale. Zinthu zopanda pake zomwe mumaphunzira, malingaliro ambiri omwe mungatenge mukakumana ndi vuto latsopano. Mtundu uwu wofananira mwachilengedwe ndi wofunikira chifukwa ... Tiyeni tichite izi, uwu ndi unyolo: poyamba ndinazindikira kuti ma graph sanagwire ntchito konse kapena sanagwire ntchito konse, zinandikumbutsa chinachake kuchokera ku zochitika zisanu ndi zitatu. Zaka zapitazo komanso zaka za wophunzira wanga, pamene tinkaphunzira za zovuta zonsezi . Izi zinandilola kuti ndipeze buku langa lakale la topology ndikulibweza m'mutu mwanga. Koma kukanakhala kuti sikunali chidziwitso chakale chimenecho, sindikanapita patsogolo kuthetsa vuto loyambalo.

Kusindikiza kwatsopano kwa buku la "The Art of Multiprocessor Programming"

Alexey: Mwanena pang'ono za bukhu lanu. Mwina si chinsinsi choyipa kwambiri chomwe mudalemba buku lodziwika kwambiri padziko lonse lapansi pa multithreading, "Art of Multiprocessor Programming". Ili kale pafupifupi zaka 11 ndipo kuyambira pamenepo yangotulutsidwa  kusindikizidwanso kosinthidwa. Kodi padzakhala kope lachiwiri?

A Maurice: Ndibwino kuti wafunsa! Zidzakhala posachedwa, m'miyezi itatu kapena kuposerapo. Pali olemba ena awiri, tinawonjezera zinthu zambiri, tinasintha gawo la foloko / kujowina kufanana, analemba gawo pa MapReduce, kuwonjezera zinthu zambiri zatsopano ndikutaya zinthu zosafunikira - zomwe zinali zosangalatsa kwambiri panthawi yolemba. kope loyamba, koma kulibe lero. Chotsatira chake chinali buku lokonzedwanso kwambiri.

Alexey: Zonse zachitika kale, zomwe zatsala ndikumasula?

A Maurice: Mitu ingapo ikufunikabe ntchito. Wofalitsa wathu (yemwe ndikuganiza kuti amatida kale) akuyesetsabe kufalitsa uthenga kuti tizigwira ntchito mwachangu. Tatsalira kwambiri. Mwamwayi, tikanachita bukuli zaka zingapo m'mbuyomo.

Alexey: Mwayi uliwonse wopeza buku latsopanoli Khrisimasi isanachitike?

A Maurice: Cholinga chathu ndi chimenechi! Koma ndaneneratu kupambana nthawi zambiri kotero kuti palibe amene amandikhulupiriranso. Mwinanso simuyenera kundikhulupirira kwambiri pankhani imeneyi.

Alexey: Mulimonsemo, iyi ndi nkhani yabwino kwambiri. Ndinalikonda kwambiri buku loyamba la bukuli. Mutha kunena kuti ndine wokonda.

A Maurice: Ndikukhulupirira kuti buku latsopanoli likhala loyenera kukhala nalo chidwi chanu, zikomo!

Momwe Transactional Memory idapangidwira

Vitaly: Funso lotsatira ndi lokhudza kukumbukira zochitika. Momwe ndikumvera, ndinu mpainiya pantchito iyi, mudayipanga panthawi yomwe palibe amene amaganizira za izi. N’chifukwa chiyani munaganiza zosamukira m’gawo limeneli? N’chifukwa chiyani kubwelako kunaoneka kukhala kofunikira kwa inu? Kodi mumaganiza kuti tsiku lina adzakhazikitsidwa mu hardware?

A Maurice: Ndakhala ndikudziwa zamalonda kuyambira masiku anga ochita kafukufuku.

Vitaly: Inde, koma izi ndizochitika zosiyana!

A Maurice: Ndinagwira ntchito ndi Elliott Moss pa ntchito yotolera zinyalala zosatsekereza. Vuto lathu linali loti tinkafuna kusintha mawu pang'ono pamtima ndipo ma aligorivimu amakhala osavuta, ndipo ena mwa iwo amatha kuchita bwino. Kugwiritsa yerekezerani-ndi-kusinthana chifukwa load-link/store-conditionalzoperekedwa ndi zomangamanga zofanana, ndizotheka kuchita zinazake, koma ndizosagwira ntchito komanso zonyansa chifukwa mumayenera kuthana ndi zigawo zosalozera. Ndikufuna kusintha mawu okumbukira ndipo ndikufunika kusintha chifukwa ndimatha kusintha cholozera chimodzi, ndiye kuti akuyenera kuloza mtundu wina wa mawonekedwe ngati chikwatu. Tinakambirana za momwe zingakhalire ngati titha kusintha hardware kuti izitha kujambula nthawi imodzi. Elliott akuwoneka kuti wazindikira izi: ngati muyang'ana ma protocol a cache, amapereka kale ntchito zambiri zofunika. Pochita zinthu mwachiyembekezo, cache coherency protocol iwona kuti pali kusamvana kwanthawi ndipo cache idzakhala. zosavomerezeka. Kodi chimachitika ndi chiani ngati mutayendetsa malonda pa cache yanu ndikugwiritsa ntchito njira zolumikizirana kuti muzindikire kusamvana? Zomangamanga zongoyerekeza zinali zosavuta kupanga. Kotero ife tinalemba izo kusindikizidwa koyamba za kukumbukira transaction. Panthawi imodzimodziyo, kampani yomwe ndinkagwira ntchito, Digital Equipment Corporation, inali kupanga purosesa yatsopano ya 64-bit yotchedwa Alpha. Chifukwa chake ndidapita ndikukafotokozera gulu lachitukuko cha Alpha za kukumbukira kwathu kodabwitsa ndipo adafunsa kuti: Kodi kampani yathu ipeza ndalama zingati ngati tiwonjeza zonse molunjika ku purosesa? Ndipo ndinalibe yankho kwathunthu pa izi, chifukwa ndine katswiri, sindine katswiri wa zamalonda. Ndinalibe choyankha. Sanasangalale kwambiri kuti sindimadziwa kalikonse.

Vitaly: Mabiliyoni! Ingonenani mabiliyoni!

A Patrick: Inde, ndi zimene ndinayenera kunena. Tsopano, m'zaka zoyambira ndi chirichonse, ndikudziwa kulemba ndondomeko ya bizinesi. Kuti mutha kunama pang'ono za kukula kwa phindu lomwe mungakhale nalo. Koma masiku amenewo zinkawoneka ngati zopanda pake, choncho ndinangoti, “Sindikudziwa.” Ngati muyang'ana mbiri ya kusindikiza pa kukumbukira zochitika, mudzawona kuti patapita chaka panali maumboni angapo kwa izo, ndiyeno kwa zaka khumi palibe amene anatchula pepala ili nkomwe. Mawuwo adawonekera cha 2004, pomwe ma multi-cores enieni adawonekera. Anthu atazindikira kuti kulemba nambala yofananira kumatha kupanga ndalama, kafukufuku watsopano adayamba. Ravi Rajwar analemba nkhani, yomwe mwanjira ina idayambitsa lingaliro la kukumbukira kwapang'onopang'ono kwa anthu ambiri. (Zolemba mkonzi: Pali buku lachiwiri la nkhaniyi, lomwe linatulutsidwa mu 2010 ndipo likupezeka kwaulere. ngati PDF). Mwadzidzidzi anthu adazindikira momwe zonsezi zingagwiritsire ntchito, momwe ma aligorivimu achikhalidwe okhala ndi maloko angachulukitsire. Chitsanzo chabwino cha chinachake chimene m’mbuyomu chinkawoneka ngati vuto losangalatsa la maphunziro. Ndipo inde, mukadandifunsa nthawi imeneyo ngati ndikuganiza kuti zonsezi zidzakhala zofunika m'tsogolomu, ndikadati: ndithudi, koma nthawi yomwe sichidziwika bwino. Mwina m'zaka 50? Pochita izi, izi zidakhala zaka khumi zokha. Zimakhala zabwino kwambiri pamene uchita chinachake ndipo patapita zaka khumi anthu amaziwona izo.

Chifukwa chiyani ndikofunikira kuchita kafukufuku m'munda wamakompyuta ogawidwa

Vitaly: Ngati tilankhula za kafukufuku watsopano, mungalangize chiyani owerenga - makina ogawa kapena ma multicore ndipo chifukwa chiyani? 

Maurice: Masiku ano n'kosavuta kupeza purosesa yamitundu yambiri, koma ndizovuta kukhazikitsa njira yogawa yowona. Ndinayamba kuwagwirira ntchito chifukwa ndinkafuna kuchita china chosiyana ndi chiphunzitso changa cha PhD. Uwu ndi upangiri womwe ndimapereka nthawi zonse kwa ophunzira atsopano: musalembe kupitiriza kwa zolemba zanu - yesani kupita njira ina. Komanso, multithreading ndikosavuta. Nditha kuyesa foloko yanga yomwe ikuyenda pa laputopu yanga osadzuka pabedi. Koma ngati mwadzidzidzi ndinkafuna kupanga dongosolo lenileni logawidwa, ndiyenera kuchita ntchito zambiri, kukopa ophunzira, ndi zina zotero. Ndine waulesi ndipo ndimakonda kugwira ntchito pazinthu zambiri. Kuyesa machitidwe amitundu yambiri kumakhalanso kosavuta kusiyana ndi kuyesa machitidwe ogawidwa, chifukwa ngakhale mu dongosolo logawidwa lopusa pali zinthu zambiri zomwe ziyenera kuyendetsedwa.

Vitaly: Mukuchita chiyani tsopano, mukufufuza blockchain? Ndi nkhani ziti zomwe muyenera kuziganizira poyamba?

A Maurice: Ndangobwera kumene nkhani yabwino kwambiri, zomwe ndinalemba pamodzi ndi wophunzira wanga, Vikram Saraf, makamaka pa nkhani Msonkhano wa Tokenomcs ku Paris masabata atatu apitawo. Iyi ndi nkhani yokhudzana ndi machitidwe omwe amagawidwa, momwe tikupangira kupanga Ethereum kukhala ndi ulusi wambiri. Pakadali pano, ma contract anzeru (code yomwe imayenda pa blockchain) imachitika motsatizana. Tidalemba nkhani m'mbuyomu yomwe idakamba za njira yogwiritsira ntchito zongopeka kuti zifulumizitse ntchitoyi. Tinatenga malingaliro ambiri kuchokera ku mapulogalamu ogwiritsira ntchito kukumbukira ndipo tinati ngati mupanga malingalirowa kukhala gawo la makina enieni a Etherium, ndiye kuti zonse zidzagwira ntchito mofulumira. Koma chifukwa cha izi ndikofunikira kuti palibe mikangano ya data pamakontrakitala. Ndiyeno tinkaganiza kuti m’moyo weniweni mulibe mikangano yoteroyo. Koma tinalibe njira yodziwira. Kenako zidatichitikira kuti tinali ndi pafupifupi zaka khumi za mbiri yakale ya mgwirizano m'manja mwathu, kotero tinataya blockchain ya Ethereum ndikudzifunsa tokha: Kodi chingachitike ndi chiyani ngati zolemba zakalezi zikanaphedwa mofanana? Tinapeza kuwonjezeka kwakukulu kwa liwiro. M'masiku oyambirira a Ethereum, liwiro linakula kwambiri, koma lero chirichonse chiri chovuta kwambiri, chifukwa pali mapangano ochepa komanso mwayi wa mikangano pa deta yomwe imafuna serialization yakhala yapamwamba. Koma zonsezi ndi ntchito yoyesera ndi deta yeniyeni ya mbiri yakale. Ubwino wa blockchain ndikuti umakumbukira chilichonse kwamuyaya, kotero titha kubwerera m'mbuyo ndikuwerenga zomwe zikadachitika tikadagwiritsa ntchito ma aligorivimu osiyanasiyana kuyendetsa kachidindo. Kodi anthu akale akadakonda bwanji lingaliro lathu latsopanoli? Kufufuza kotereku kumakhala kosavuta komanso kosangalatsa kuchita, chifukwa pali chinthu chomwe chimayang'anira chilichonse ndikulemba chilichonse. Ichi ndi chinthu chofanana kwambiri ndi chikhalidwe cha anthu kusiyana ndi chitukuko cha ma algorithms.

Kodi kupanga ma algorithms kwayima komanso momwe mungapitirire?

Vitaly: Nthawi yofunsa funso lomaliza! Kodi zikuwoneka ngati kupita patsogolo kwamitundu yosiyanasiyana ya data kukuchepera chaka chilichonse? Kodi mukuganiza kuti tafika pachimake pakumvetsetsa kwathu kapangidwe ka data kapena pakhala kusintha kwakukulu? Mwina pali malingaliro anzeru omwe angasinthiretu chilichonse?

A Maurice: N'kutheka kuti tafika pamalo okwera kwambiri chifukwa cha zomanga zakale. Koma mapangidwe a deta a zomangamanga zatsopano akadali malo odalirika kwambiri. Ngati mukufuna kupanga ma data a, tinene, ma accelerator a hardware, ndiye kuti mapangidwe a data a GPU ndi osiyana kwambiri ndi ma data a CPU. Mukapanga mapangidwe amtundu wa blockchains, muyenera kuwononga zidutswa za data ndikuziyika ngati zina Mtengo wa Merkle, kupewa kuba. Posachedwapa pakhala pali ntchito zambiri m’derali, ndipo ambiri akuchita ntchito yabwino kwambiri. Koma ndikuganiza zomwe zidzachitike ndikuti zomanga zatsopano ndi ntchito zatsopano zidzatsogolera kuzinthu zatsopano za data. Ntchito zakale ndi zomangamanga - sipangakhalenso malo ambiri oti mufufuze. Koma ngati mutachokapo ndikuyang'ana kupyola m'mphepete mwake, mudzawona zinthu zopenga zomwe anthu ambiri saziwona mozama - ndipamene zinthu zonse zosangalatsa zimachitikadi.

Vitaly: Chifukwa chake, kuti ndikhale wofufuza wotchuka kwambiri, ndidayenera kupanga zomanga zanga :)

Maurice: Mutha "kuba" zomanga zatsopano za wina - zikuwoneka zosavuta!

Ndimagwira ntchito ku Brown University

Vitaly: Kodi mungatiuze zambiri za Brown Universitymumagwira ntchito kuti? Palibe zambiri zomwe zimadziwika za iye pankhani yaukadaulo wazidziwitso. Zocheperapo za MIT, mwachitsanzo.

Maurice: Brown University ndi imodzi mwasukulu zakale kwambiri ku United States. Ndikuganiza kuti Harvard yekha ndi wamkulu pang'ono. Brown ndi gawo la otchedwa Ivy League, omwe ndi gulu la mayunivesite asanu ndi atatu akale kwambiri. Harvard, Brown, Cornell, Yale, Columbia, Dartmouth, Pennsylvania, Princeton. Ndi yunivesite yakale, yaying'ono komanso yolemekezeka. Cholinga chachikulu ndi maphunziro a zaluso zaufulu. Sikuyesera kukhala ngati MIT, MIT ndi yapadera komanso yaukadaulo. Brown ndi malo abwino ophunzirira Russian Literature kapena Classical Greek, komanso, Computer Science. Imayang'ana kwambiri maphunziro athunthu. Ambiri mwa ophunzira athu amapita ku Facebook, Apple, Google - kotero ndikuganiza kuti ophunzira athu alibe vuto lopeza ntchito m'makampani. Ndinapita kukagwira ntchito ku Brown chifukwa ndinali nditagwirapo ntchito pa Digital Equipment Corporation ku Boston. Iyi inali kampani yomwe idapanga zinthu zambiri zosangalatsa, koma idakana kufunikira kwa makompyuta amunthu. Kampani yomwe inali ndi tsoka lovuta, omwe oyambitsa ake anali osintha achichepere, sanaphunzirepo kanthu ndipo sanaiwale kalikonse, motero adasiya osintha kusintha kupita ku otsutsa mkati mwa zaka khumi ndi ziwiri. Ankakonda kuchita nthabwala kuti makompyuta awo anali m’galajamo, ndithudi, garaja yosiyidwa. Zikuwonekeratu kuti zidawonongedwa ndi makampani osinthika kwambiri. Zitadziwika kuti kampaniyo ili m’mavuto, ndinaimbira foni mnzanga wina wa ku Brown, kumene kuli pafupi ola limodzi kunja kwa Boston. Sindinkafuna kuchoka ku Boston panthawiyo chifukwa ku mayunivesite ena kunalibe malo ambiri. Iyi inali nthawi yomwe kunalibe ntchito zambiri mu Computer Science monga momwe zilili pano. Ndipo Brown anali ndi mwayi, sindinasowe kusuntha nyumba yanga, sindinasowe kusuntha banja langa, ndipo ndimakonda kwambiri kukhala ku Boston! Ndimomwe ndinaganiza zopita ku Brown. Ndimachikonda. Ophunzirawo ndi odabwitsa, choncho sindinayesepo kupita kwinakwake. Pa sabata, ndinagwira ntchito ku Microsoft kwa chaka chimodzi, ndinapita ku Technion ku Haifa kwa chaka chimodzi, ndipo tsopano ndidzakhala ku Algorand. Ndili ndi anzanga ambiri kulikonse ndipo chifukwa chake malo omwe tikukhala m'makalasi athu sizofunikira. Koma chofunika kwambiri ndi ophunzira, iwo ndi abwino kwambiri pano. Sindinayesepo kupita kwinakwake chifukwa ndili wosangalala kuno.

Komabe ngakhale kutchuka kwa Brown ku United States, sakudziwika modabwitsa kunja. Monga mukuonera, tsopano ndikuchita chilichonse chotheka kuti ndikonze zinthu.

Kusiyana pakati pa kafukufuku ku yunivesite ndi mkati mwa bungwe

Vitaly: Chabwino, funso lotsatira ndi la Zida Zamakono. Munali komweko ngati wofufuza. Kodi pali kusiyana kotani pakati pa kugwira ntchito mu dipatimenti ya R&D yakampani yayikulu ndikugwira ntchito ku yunivesite? Kodi ubwino ndi kuipa kwake ndi chiyani?

Maurice: Kwa zaka makumi awiri ndimagwira ntchito ku Microsoft, ndimagwira ntchito limodzi ndi antchito a Sun Microsystems, Oracle, Facebook, ndipo tsopano Algorand. Kutengera zonsezi, ndikufuna kunena kuti ndizotheka kuchita kafukufuku wamaphunziro oyamba m'makampani komanso m'mayunivesite. Kusiyana kwakukulu ndikuti mu kampani mumagwira ntchito ndi anzanu. Ngati mwadzidzidzi ndili ndi lingaliro la polojekiti yomwe kulibe, ndiyenera kutsimikizira anzanga kuti ili ndi lingaliro labwino. Ngati ndili ku Brown, ndiye kuti nditha kuuza ophunzira anga: tiyeni tigwiritse ntchito antigravity! Iwo amapita kwa wina kapena kutenga ntchito. Inde, ndiyenera kupeza ndalama, ndiyenera kulemba fomu yofunsira thandizo, ndi zina zotero. Mulimonsemo, nthawi zonse padzakhala ophunzira ambiri, ndipo mudzatha kupanga zisankho unilaterally. Koma ku yunivesite simudzagwira ntchito ndi anthu a msinkhu wanu. M'dziko la kafukufuku wamafakitale, choyamba muyenera kutsimikizira aliyense kuti polojekiti yanu ndiyofunika kuchita. Sindingathe kuyitanitsa aliyense. Ndipo njira ziwirizi zogwirira ntchito ndizofunika, chifukwa ngati mukugwira ntchito yopenga kwambiri ndipo anzanu ndi ovuta kuwatsimikizira, ndizosavuta kutsimikizira ophunzira omaliza maphunziro - makamaka ngati mukuwalipira. Ngati mukugwira ntchito yomwe imafuna chidziwitso chochuluka komanso luso lakuya, ndiye kuti mukufunikira anzanu omwe anganene kuti "ayi, zimangochitika kuti ndikumvetsa m'dera lino ndipo lingaliro lanu ndi loipa, silingagwire ntchito." Izi ndizothandiza kwambiri pakuwononga nthawi. Komanso, ngati m'ma laboratories a mafakitale mumathera nthawi yochuluka mukulemba malipoti, ndiye kuti ku yunivesite mumathera nthawiyi mukuyesera kupeza ndalama. Ngati ndikufuna kuti ophunzira athe kupita kwinakwake, ndiyenera kupeza ndalama zake kwinakwake. Ndipo udindo wanu ku yunivesite ukakhala wofunika kwambiri, umakhala ndi nthawi yambiri yopezera ndalama. Kotero tsopano inu mukudziwa chimene ine ntchito - katswiri wopemphapempha! Monga mmodzi wa amonke amene amayenda ndi mbale ya chopereka. Nthawi zambiri, ntchito ziwirizi zimayenderana. Ndicho chifukwa chake ndimayesetsa kukhala ndi moyo ndikusunga mapazi anga pansi padziko lonse lapansi.

Vitaly: Zikuoneka kuti kutsimikizira kampani n’kovuta kwambiri kuposa kutsimikizira asayansi ena.

A Maurice: Zovuta kwambiri, ndi zina zambiri. Kuphatikiza apo, m'malo osiyanasiyana ndizosiyana: ena amachita kafukufuku wathunthu, pomwe ena amangoyang'ana mutu wawo. Ngati nditapita ku Microsoft kapena Facebook ndikuti: tiyeni tipange anti-gravity, sangayamikire. Koma ngati ndinanena chimodzimodzi kwa ophunzira anga omaliza maphunziro, amatha kugwira ntchito nthawi yomweyo, ngakhale tsopano ndikanakhala ndi mavuto - pambuyo pake, ndiyenera kupeza ndalama za izi. Koma malinga ngati mukufuna kuchita zinthu zogwirizana ndi zolinga za kampaniyo, kampaniyo ikhoza kukhala malo abwino kwambiri ochitira kafukufuku.

Hydra ndi SPTDC

Vitaly: Mafunso anga akutha, choncho tiyeni tikambirane pang’ono za ulendo wopita ku Russia.

A Maurice: Inde, ndikuyembekezera mwachidwi kubwerera ku St.

Alexey: Ndine wolemekezeka kukhala nanu nafe chaka chino. Iyi ndi nthawi yanu yachiwiri ku St. Petersburg, sichoncho?

A Maurice: Wachitatu kale!

Alexey: Ndikumva, koma Chithunzi cha SPTDC - ndithudi wachiwiri. Nthawi yomaliza sukulu inaitanidwa Mtengo wa magawo SPTCC, tsopano tasintha chilembo chimodzi (C mpaka D, Concurrent to Distributed) kuti titsimikize kuti pali madera ambiri okhudzana ndi kugawidwa kwa makompyuta chaka chino. Kodi munganene mawu ochepa za malipoti anu ku Sukulu ndi Msonkhano wa Hydra?

A Maurice: Kusukulu ndikufuna kukambirana za mfundo za blockchain ndi zomwe mungachite nazo. Ndikufuna kuwonetsa kuti blockchains ndi ofanana kwambiri ndi mapulogalamu amitundu yambiri omwe timawadziwa, koma ndi ma nuances awo, ndipo kusiyana kumeneku ndikofunikira kumvetsetsa. Ngati mungalakwitse pa intaneti, zimangokwiyitsa. Ngati mulemba buggy code mu pulogalamu yazachuma, wina adzabera ndalama zanu zonse. Izi ndizosiyana kwambiri ndi maudindo ndi zotsatira zake. Ndilankhula pang'ono za umboni wa ntchito, za makontrakitala anzeru, zakusinthana pakati pa blockchains zosiyanasiyana.

Padzakhala oyankhula ena omwe akugwira ntchito pafupi ndi ine omwe ali ndi zonena za blockchain, ndipo tinagwirizana kuti tigwirizane kuti nkhani zathu zigwirizane bwino. Koma pa lipoti la uinjiniya, ndikufuna kuuza omvera ambiri mafotokozedwe omveka a chifukwa chake simuyenera kukhulupirira zonse zomwe mumamva za blockchains, chifukwa chiyani blockchains ndi gawo lalikulu, momwe zimayenderana ndi malingaliro ena odziwika, komanso chifukwa chake tiyenera kuyang'ana molimba mtima. ku tsogolo.

Alexey: Kuphatikiza apo, ndikufuna kunena kuti izi sizichitika mwanjira ya msonkhano kapena gulu la ogwiritsa ntchito, monga momwe zidalili zaka ziwiri zapitazo. Tinaganiza zochitira msonkhano waung’ono pafupi ndi sukuluyo. Chifukwa chake n'chakuti titatha kulankhulana ndi Peter Kuznetsov, tinazindikira kuti sukuluyi ili ndi anthu zana, mwina 120. Nthawi yomweyo, pali mainjiniya ambiri omwe akufuna kulumikizana nanu, kupezeka paziwonetsero, ndipo amakhala ndi chidwi ndi mutuwo. Pachifukwa ichi tapanga msonkhano watsopano wotchedwa Hydra. Mwa njira, malingaliro aliwonse chifukwa chiyani Hydra?

A Maurice: Chifukwa padzakhala okamba XNUMX? Ndipo mitu yawo ikhoza kudulidwa, ndipo okamba atsopano adzakula m'malo mwawo?

Alexey: Lingaliro labwino pakukulitsa olankhula atsopano. Koma kunena zoona, pali nkhani apa. Kumbukirani nthano ya Odysseus, komwe adayenera kuyenda panyanja Scylla ndi Charybdis? Hydra ndi chinthu chonga Charybdis. Nkhani ndi yakuti kamodzi ndinalankhula pa msonkhano ndi analankhula za multithreading. Panali njira ziwiri zokha pamsonkhanowu. Kumayambiriro kwa lipotilo, ndinauza omvera muholoyo kuti tsopano ali ndi chisankho pakati pa Scylla ndi Charybdis. Chilombo changa chauzimu ndi Charybdis chifukwa Charybdis ali ndi mitu yambiri ndipo mutu wanga ndi wamitundu yambiri. Umu ndi momwe mayina amisonkhano amawonekera.

Mulimonse momwe zingakhalire, tatha ndi mafunso ndi nthawi. Chifukwa chake, zikomo, abwenzi, pakufunsana kwakukulu, ndikukuwonani ku SPTDC School ndi Hydra 2019!

Mukhoza kupitiriza kukambirana ndi Maurice pa msonkhano wa Hydra 2019, womwe udzachitike pa July 11-12, 2019 ku St. Adzabwera ndi lipoti "Blockchains ndi tsogolo la makompyuta ogawidwa". Matikiti angagulidwe patsamba lovomerezeka.

Source: www.habr.com