Ukucindezelwa kwedatha ku-Apache Ignite. Isipiliyoni sikaSber

Lapho usebenza ngamanani amakhulu wedatha, inkinga yokuntuleka kwesikhala sediski ingavela ngezinye izikhathi. Enye indlela yokuxazulula le nkinga ukucindezelwa, ngenxa yokuthi, kumishini efanayo, ungakwazi ukukhokhela ukukhulisa umthamo wesitoreji. Kulesi sihloko, sizobheka ukuthi ukucindezelwa kwedatha kusebenza kanjani ku-Apache Ignite. Lesi sihloko sizochaza kuphela izindlela zokucindezelwa kwediski ezisetshenziswe ngaphakathi komkhiqizo. Ezinye izindlela zokucindezelwa kwedatha (phezu kwenethiwekhi, enkumbulweni), kungakhathaliseki ukuthi kwenziwa noma cha, kuzohlala ngaphandle kobubanzi.

Ngakho-ke, ngemodi yokuphikelela inikwe amandla, ngenxa yezinguquko kudatha kunqolobane, i-Ignite iqala ukubhala kudiski:

1. Okuqukethwe kwenqolobane
2. Bhala Phambili Ilogi (ngemuva kwalokhu kalula WAL)

Kube khona indlela yokucindezelwa kwe-WAL isikhathi eside manje, ebizwa ngokuthi i-WAL compaction. I-Apache Ignite 2.8 esanda kukhishwa yethule ezinye izindlela ezimbili ezikuvumela ukuthi ucindezele idatha kudiski: ukucindezelwa kwekhasi lediski ukuze ucindezele okuqukethwe kwe-cache kanye nokuminyaniswa kwesifinyezo sekhasi le-WAL ukuze ucindezele okufakiwe kwe-WAL. Imininingwane eyengeziwe ngazo zontathu lezi zindlela ngezansi.

Ukucindezelwa kwekhasi lediski

Kanjani lo msebenzi

Okokuqala, ake sibheke kafushane ukuthi i-Ignite igcina kanjani idatha. Imemori yekhasi isetshenziselwa ukugcina. Usayizi wekhasi usethwe ekuqaleni kwe-node futhi awukwazi ukushintshwa ezigabeni zakamuva; futhi, usayizi wekhasi kufanele ube amandla amabili kanye nokuphindaphinda kosayizi webhulokhi yesistimu yefayela. Amakhasi alayishwa ku-RAM esuka kudiski njengoba kudingeka; usayizi wedatha kudiski ungase udlule inani le-RAM enikeziwe. Uma singekho isikhala esanele ku-RAM sokulayisha ikhasi kudiski, amakhasi amadala, angasasetshenziswa azokhishwa ku-RAM.

Idatha igcinwa kudiski ngendlela elandelayo: ifayela elihlukile lenziwa ukwahlukaniswa ngakunye kweqembu lenqolobane ngayinye; kuleli fayela, amakhasi avela ngokulandelana ngokulandelana ngokulandelana kwenkomba ekhuphukayo. Isihlonzi sekhasi esigcwele siqukethe isihlonzi seqembu lenqolobane, inombolo yokuhlukanisa, nenkomba yekhasi efayeleni. Ngakho, sisebenzisa isihlonzi sekhasi eligcwele, singakwazi ukunquma ngokuhlukile ifayela kanye ne-offset kufayela lekhasi ngalinye. Ungafunda kabanzi mayelana nenkumbulo yokupheja esihlokweni se-Apache Ignite Wiki: Ignite Isitolo Esiqhubekayo - ngaphansi kwe-hood.

Indlela yokucindezela ikhasi lediski, njengoba ungase uqagele egameni, isebenza ezingeni lekhasi. Uma le nqubo inikwe amandla, idatha ku-RAM icutshungulwa njengoba kunjalo, ngaphandle kokucindezelwa, kodwa uma amakhasi alondolozwe kusuka ku-RAM kuya kudiski, ayacindezelwa.

Kodwa ukucindezela ikhasi ngalinye ngokwalo akusona isixazululo senkinga; udinga ukuthi ngandlela thize unciphise usayizi wamafayela edatha angumphumela. Uma usayizi wekhasi ungasalungisiwe, ngeke sisakwazi ukubhala amakhasi efayelini ngokulandelana, ngoba lokhu kungadala izinkinga eziningi:

• Ngokusebenzisa inkomba yekhasi, ngeke sikwazi ukubala i-offset etholakala ngayo kufayela.
• Akucaci ukuthi yini okufanele yenziwe ngamakhasi angekho ekugcineni kwefayela futhi ashintshe usayizi wawo. Uma usayizi wekhasi wehla, isikhala esalikhulula siyanyamalala. Uma usayizi wekhasi ukhula, udinga ukubheka indawo entsha kufayela yawo.
• Uma ikhasi lihamba ngamabhayithi amaningi okungewona ukuphindaphinda kosayizi webhulokhi yesistimu yefayela, khona-ke ukulifunda noma ukulibhala kuzodinga ukuthinta elinye ibhulokhi yesistimu yefayela, okungaholela ekonakaleni kokusebenza.

Ukuze ugweme ukuxazulula lezi zinkinga ngezinga lakhona, ukucindezelwa kwekhasi lediski ku-Apache Ignite kusebenzisa indlela yesistimu yefayela ebizwa ngokuthi amafayela angama-sparse. Ifayela elincane yilelo lapho ezinye izifunda ezigcwaliswe uziro zingamakwa khona ngokuthi "izimbobo". Kulesi simo, awekho amabhulokhi esistimu yefayela azokwabelwa ukugcina lezi zimbobo, okuholela ekongeni isikhala sediski.

Kunengqondo ukuthi ukuze ukhulule ibhulokhi yesistimu yefayela, usayizi wembobo kufanele ube mkhulu noma ulingane nebhulokhi yesistimu yefayela, okubeka umkhawulo owengeziwe kusayizi wekhasi kanye ne-Apache Ignite: ukuze ukucindezela kube nanoma yimuphi umphumela, usayizi wekhasi kufanele ube mkhulu ngokuqinile kunosayizi webhulokhi yesistimu yefayela . Uma usayizi wekhasi ulingana nosayizi webhulokhi, ngeke sikwazi ukukhulula ibhulokhi eyodwa, ngoba ukuze ukhulule ibhulokhi eyodwa, ikhasi elicindezelwe kufanele libe namabhayithi angu-0. Uma usayizi wekhasi ulingana nosayizi wamabhulokhi angu-2 noma angu-4, sesizokwazi kakade ukukhulula okungenani ibhulokhi eyodwa uma ikhasi lethu licindezelwe okungenani libe ngu-50% noma u-75% ngokulandelana.

Ngakho-ke, incazelo yokugcina yokuthi umshini usebenza kanjani: Lapho ubhala ikhasi kudiski, kwenziwa umzamo wokucindezela ikhasi. Uma usayizi wekhasi elicindezelwe livumela ibhulokhi yesistimu yefayela eyodwa noma amaningi ukuthi akhululwe, khona-ke ikhasi libhalwa ngendlela ecindezelwe, futhi "imbobo" yenziwa esikhundleni samabhulokhi akhululiwe (ucingo lwesistimu lwenziwa. fallocate() ngefulegi lembobo yesibhakela). Uma usayizi wekhasi elicindezelwe ungavumeli ukuthi amabhlogo akhululwe, ikhasi ligcinwa njengoba linjalo, lingacindezelwanga. Wonke ama-offset amakhasi abalwa ngendlela efanayo nangaphandle kokucindezelwa, ngokuphindaphinda inkomba yekhasi ngosayizi wekhasi. Akukho ukuthuthwa kwamakhasi okudingekayo uwedwa. Ukususwa kwekhasi, njengangaphandle kokucindezelwa, kuwela emingceleni yamabhulokhi wesistimu yefayela.

Ekusetshenzisweni kwamanje, i-Ignite ingasebenza kuphela ngamafayela ayingcosana ngaphansi kwe-Linux OS; ngokufanelekile, ukuminyaniswa kwekhasi lediski kunganikwa amandla kuphela uma usebenzisa i-Ignite kulolu hlelo lokusebenza.

Ama-algorithms wokucindezela angasetshenziselwa ukucindezela ikhasi lediski: ZSTD, LZ4, Snappy. Ngaphezu kwalokho, kunemodi yokusebenza (SKIP_GARBAGE), lapho isikhala esingasetshenzisiwe kuphela ekhasini sikhishelwa ngaphandle ngaphandle kokusebenzisa ukucindezela kudatha esele, okunciphisa umthwalo ku-CPU uma kuqhathaniswa nama-algorithms afakwe ohlwini lwangaphambilini.

Umthelela Wokusebenza

Ngeshwa, angizange ngenze izilinganiso zokusebenza zangempela ezindlini zangempela, njengoba singahleli ukusebenzisa le mishini ekukhiqizeni, kodwa singaqagela ngokusobala ukuthi sizolahlekelwa kuphi nokuthi sizowina kuphi.

Ukwenza lokhu, sidinga ukukhumbula ukuthi amakhasi afundwa futhi abhalwe kanjani lapho efinyelelwe:

• Lapho kwenziwa umsebenzi wokufunda, liseshwa kuqala ku-RAM; uma ukusesha kungaphumeleli, ikhasi lilayishwa ku-RAM lisuka kudiski ngochungechunge olufanayo olufundayo.
• Uma kwenziwa umsebenzi wokubhala, ikhasi eliku-RAM limakwa njengelingcolile, kodwa ikhasi aligcinwa ngokoqobo kudiski ngokushesha ngochungechunge olubhalayo. Wonke amakhasi angcolile alondolozwa kudiski kamuva enqubweni yokuhlola emicu ehlukene.

Ngakho umthelela ekusebenzeni kokufunda uwukuthi:

• Okuhle (idiski IO), ngenxa yokuncipha kwenani lamabhulokhi esistimu yefayela afundiwe.
• Negative (CPU), ngenxa yomthwalo owengeziwe odingwa isistimu yokusebenza ukuze isebenze ngamafayela ayingcosana. Kungenzeka futhi ukuthi imisebenzi eyengeziwe ye-IO izovela ngokusobala lapha ukuze kugcinwe ukwakheka kwefayela elincane eliyinkimbinkimbi (ngeshwa, angiyazi yonke imininingwane yokuthi amafayela ayingcosana asebenza kanjani).
• I-Negative (CPU), ngenxa yesidingo sokucisha amakhasi.
• Awukho umthelela emisebenzini yokubhala.
• Umthelela ohlelweni lokuhlola (yonke into lapha iyafana nokusebenza kokufunda):
• Okuhle (idiski IO), ngenxa yokuncipha kwenani lamabhulokhi wesistimu yefayela ebhaliwe.
• Negative (CPU, ngokunokwenzeka disk IO), ngenxa yokusebenza ngamafayela ayingcosana.
• Negative (CPU), ngenxa yesidingo sokucindezelwa kwekhasi.

Iluphi uhlangothi lwesikali oluzothipha isikali? Konke lokhu kuncike kakhulu endaweni, kodwa ngithambekele ekukholweni ukuthi ukucindezelwa kwekhasi lediski kuzoholela ekonakaleni kokusebenza kumasistimu amaningi. Ngaphezu kwalokho, ukuhlolwa kwamanye ama-DBMS asebenzisa indlela efanayo ngamafayela ayingcosana kubonisa ukwehla kokusebenza lapho ukucindezela kunikwe amandla.

Unganika amandla futhi ulungiselele kanjani

Njengoba kushiwo ngenhla, inguqulo encane ye-Apache Ignite esekela ukucindezelwa kwekhasi lediski ingu-2.8 futhi uhlelo lokusebenza lwe-Linux kuphela olusekelwayo. Nika amandla futhi ulungiselele kanje:

• Kumelwe kube nemojula yokucindezelwa kwe-ignite ku-class-path. Ngokuzenzakalelayo, itholakala ekusabalaliseni kwe-Apache Ignite kumkhombandlela we-libs/ongakukhetha futhi ayifakiwe kumzila wekilasi. Ungakwazi ukumane unyuse uhla lwemibhalo ukhuphuke ileveli eyodwa uye ku-libs bese kuthi lapho ulisebenzisa nge-ignite.sh luzovulwa ngokuzenzakalelayo.
• Ukuphikelela kufanele kunikwe amandla (Kunikwe amandla nge DataRegionConfiguration.setPersistenceEnabled(true)).
• Usayizi wekhasi kufanele ube mkhulu kunosayizi webhulokhi yesistimu yefayela (ungayisetha usebenzisa DataStorageConfiguration.setPageSize() ).
• Kunqolobane ngayinye edatha yayo idinga ukucindezelwa, kufanele ulungiselele indlela yokucindezela kanye (ngokuzithandela) nezinga lokuminyanisa (izindlela CacheConfiguration.setDiskPageCompression() , CacheConfiguration.setDiskPageCompressionLevel()).

Ukuhlanganiswa kwe-WAL

Kanjani lo msebenzi

Iyini i-WAL futhi kungani idingeka? Kafushane kakhulu: leli logi eliqukethe zonke izehlakalo ezigcina ziguqule isitoreji sekhasi. Kudingeka ngokuyinhloko ukuze ukwazi ukululama uma kwenzeka ukuwa. Noma yikuphi ukusebenza, ngaphambi kokunikeza amandla okulawula kumsebenzisi, kufanele kuqala kuqophe umcimbi ku-WAL, ukuze uma kwenzeka ukwehluleka, kudlalwe kubuyelwe kulogi futhi kubuyiselwe yonke imisebenzi umsebenzisi athole impendulo yayo ngempumelelo, noma ngabe le misebenzi. wayengenaso isikhathi sokuboniswa ekugcinweni kwekhasi kudiski (sekuvele ngenhla Kuchazwe ukuthi ukubhala kwangempela esitolo sekhasi kwenziwa ngenqubo ebizwa ngokuthi "i-checkpointing" ngokulibaziseka okuthile ngemicu ehlukene).

Okufakiwe ku-WAL kuhlukaniswe ngokwengqondo nangokomzimba. Eziphuphuthekayo zingokhiye futhi ziyazazisa ngokwazo. Okoqobo - kubonisa izinguquko emakhasini esitolo samakhasi. Nakuba amarekhodi anengqondo engaba usizo kwezinye izimo, amarekhodi aphathekayo adingeka kuphela ukuze alulame uma kwenzeka ingozi futhi amarekhodi adingeka kuphela kusukela endaweni yokuhlola eyimpumelelo yokugcina. Lapha ngeke singene ngemininingwane futhi sichaze ukuthi kungani isebenza ngale ndlela, kepha labo abanentshisekelo bangabhekisa esihlokweni esesivele sishiwo ku-Apache Ignite Wiki: Ignite Isitolo Esiqhubekayo - ngaphansi kwe-hood.

Kuvame ukuba namarekhodi amaningana werekhodi ngalinye elinengqondo. Okusho ukuthi, isibonelo, ukufakwa okukodwa kunqolobane kuthinta amakhasi amaningana kumemori yekhasi (ikhasi elinedatha ngokwalo, amakhasi anezinkomba, amakhasi anohlu lwamahhala). Kwezinye izivivinyo zokwenziwa, ngithole ukuthi amarekhodi aphathekayo athatha kufika ku-90% wefayela le-WAL. Kodwa-ke, ayadingeka isikhathi esifushane kakhulu (ngokuzenzakalelayo, isikhawu phakathi kwezindawo zokuhlola imizuzu emi-3). Kungaba okunengqondo ukususa le datha ngemva kokulahlekelwa ukuhambisana kwayo. Yilokhu kanye okwenziwa yi-WAL compaction mechanism: isusa amarekhodi aphathekayo bese icindezela amarekhodi anengqondo asele kusetshenziswa i-zip, kuyilapho usayizi wefayela wehliswa kakhulu (ngezinye izikhathi izikhathi ezingamashumi).

Ngokomzimba, i-WAL iqukethe amasegimenti ambalwa (okuzenzakalelayo ayi-10) osayizi ogxilile (okuzenzakalelayo okungu-64MB), abhalwe ngaphezulu ngendlela eyindilinga. Ngokushesha lapho ingxenye yamanje isigcwalisiwe, ingxenye elandelayo inikezwa njengeyamanje, futhi ingxenye egcwalisiwe ikopishwa kungobo yomlando ngochungechunge oluhlukile. Ukuhlanganiswa kwe-WAL sekuvele kusebenza namasegimenti engobo yomlando. Futhi, njengentambo ehlukile, iqapha ukwenziwa kwendawo yokuhlola futhi iqala ukucindezelwa ezingxenyeni zengobo yomlando lapho amarekhodi aphathekayo angasadingeki.

Umthelela Wokusebenza

Njengoba ukuhlanganiswa kwe-WAL kusebenza njengochungechunge oluhlukile, akufanele kube nomthelela oqondile emisebenzini eyenziwayo. Kodwa isabeka umthwalo ongemuva owengeziwe ku-CPU (ukucindezela) kanye nediski (ukufunda ingxenye ngayinye ye-WAL kusuka kungobo yomlando nokubhala izingxenye ezicindezelwe), ngakho-ke uma uhlelo lusebenza ngomthamo walo omkhulu, luzophinde luholele ekulimazeni kokusebenza.

Unganika amandla futhi ulungiselele kanjani

Ungavumela ukuhlanganisa kwe-WAL usebenzisa indawo WalCompactionEnabled в DataStorageConfiguration (DataStorageConfiguration.setWalCompactionEnabled(true)). Futhi, usebenzisa indlela ye-DataStorageConfiguration.setWalCompactionLevel(), ungasetha izinga lokucindezela uma unganelisekile ngevelu emisiwe (BEST_SPEED).

Ukucindezelwa kwesifinyezo sekhasi le-WAL

Kanjani lo msebenzi

Sesivele sitholile ukuthi kumarekhodi we-WAL ahlukaniswe abe anengqondo futhi aphathekayo. Ngoshintsho ngalunye ekhasini ngalinye, irekhodi eliphathekayo le-WAL lenziwa kumemori yekhasi. Amarekhodi aphathekayo, wona, nawo ahlukaniswe ama-subtypes ama-2: irekhodi lesifinyezo sekhasi kanye nerekhodi le-delta. Ngaso sonke isikhathi lapho sishintsha okuthile ekhasini futhi sikudlulisa kusuka esimweni esihlanzekile kuya esimweni esingcolile, ikhophi ephelele yaleli khasi igcinwa ku-WAL (irekhodi lesifinyezo sekhasi). Ngisho noma sishintshe ibhayithi eyodwa kuphela ku-WAL, irekhodi lizoba likhulu kancane kunosayizi wekhasi. Uma sishintsha okuthile ekhasini elivele lingcolile, irekhodi le-delta liyakhiwa nge-WAL, elibonisa izinguquko kuphela uma kuqhathaniswa nesimo sangaphambilini sekhasi, kodwa hhayi lonke ikhasi. Njengoba ukusetha kabusha isimo samakhasi kusuka kokungcolile kuya ekuhlanzeni kwenziwa ngesikhathi senqubo yokuhlola, ngokushesha ngemva kokuqala kwendawo yokuhlola, cishe wonke amarekhodi angokwenyama azoba nezifinyezo zamakhasi kuphela (njengoba wonke amakhasi ngokushesha ngemva kokuqala kwendawo yokuhlola ahlanzekile) , khona-ke njengoba sisondela endaweni yokuhlola elandelayo, ingxenye yerekhodi ye-delta iqala ukukhula futhi isethwe kabusha ekuqaleni kwendawo yokuhlola elandelayo. Izilinganiso kwezinye izivivinyo zokwenziwa zibonise ukuthi ukwabelana kwezifinyezo zekhasi kuvolumu ephelele yamarekhodi aphathekayo kufinyelela ku-90%.

Umqondo wokucindezelwa kwesifinyezo sekhasi le-WAL uwukucindezela izifinyezo zekhasi usebenzisa ithuluzi lokuminyanisa ikhasi elenziwe ngomumo (bona ukucindezela kwekhasi lediski). Ngesikhathi esifanayo, ku-WAL, amarekhodi agcinwa ngokulandelana kumodi yokufaka kuphela futhi asikho isidingo sokubopha amarekhodi emingceleni yamabhulokhi wesistimu yefayela, ngakho-ke lapha, ngokungafani nendlela yokucindezela ikhasi lediski, asiwadingi amafayela amancane konke; ngokufanele, le nqubo izosebenza hhayi kuphela ku-OS Linux. Ngaphezu kwalokho, akusabalulekile kithi ukuthi sikwazile ukuminyanisa ikhasi kangakanani. Ngisho noma sikhulule i-byte engu-1, lokhu sekuvele kuwumphumela omuhle futhi singakwazi ukulondoloza idatha ecindezelwe ku-WAL, ngokungafani nokuminyanisa kwekhasi lediski, lapho silondoloza khona ikhasi elicindezelwe kuphela uma sikhulule ibhulokhi yesistimu yefayela engaphezu kwe-1.

Amakhasi ayidatha ecindezela kakhulu, isabelo sawo kuvolumu ye-WAL iphezulu kakhulu, ngakho-ke ngaphandle kokushintsha ifomethi yefayela le-WAL singathola ukuncishiswa okukhulu kosayizi walo. Ukucindezela, okuhlanganisa namarekhodi anengqondo, kungadinga ushintsho kufomethi nokulahlekelwa ukuhambisana, isibonelo, kubathengi bangaphandle abangase babe nesithakazelo kumarekhodi anengqondo, kodwa angeke aholele ekuncishisweni okuphawulekayo kosayizi wefayela.

Njengokucindezela ikhasi lediski, ukucindezelwa kwesifinyezo sekhasi le-WAL kungasebenzisa i-ZSTD, LZ4, i-Snappy compression algorithms, kanye nemodi ethi SKIP_GARBAGE.

Umthelela Wokusebenza

Akunzima ukuqaphela ukuthi ukunika amandla ngokuqondile ukucindezelwa kwesifinyezo sekhasi le-WAL kuthinta kuphela imicu ebhala idatha kumemori yekhasi, okungukuthi, lezo zintambo ezishintsha idatha kunqolobane. Ukufunda amarekhodi angokwenyama kusuka ku-WAL kwenzeka kanye kuphela, okwamanje i-node iphakanyiswa ngemva kokuwa (futhi kuphela uma iwe ngesikhathi sokuhlola).

Lokhu kuthinta imicu eshintsha idatha ngale ndlela elandelayo: sithola umphumela omubi (CPU) ngenxa yesidingo sokucindezela ikhasi isikhathi ngasinye ngaphambi kokubhalela kudiski, kanye nomphumela omuhle (idiski IO) ngenxa yokuncipha kwenani idatha ebhaliwe. Ngakho-ke, konke kulula lapha: uma ukusebenza kwesistimu kunqunyelwe yi-CPU, sithola ukuwohloka okuncane, uma kunqunyelwe i-disk I / O, sithola ukwanda.

Ngokungaqondile, ukwehlisa usayizi we-WAL kuphinde kuthinte (okuhle) imifudlana elahla amasegimenti e-WAL kungobo yomlando kanye nokusakaza kokuhlanganisa kwe-WAL.

Ukuhlolwa kokusebenza kwangempela endaweni yethu kusetshenziswa idatha yokwenziwa kubonise ukunyuka okuncane (umphumela ukhuphuke ngo-10% -15%, ukubambezeleka kwehle ngo-10% -15%).

Unganika amandla futhi ulungiselele kanjani

Ubuncane benguqulo ye-Apache Ignite: 2.8. Nika amandla futhi ulungiselele kanje:

• Kumelwe kube nemojula yokucindezelwa kwe-ignite ku-class-path. Ngokuzenzakalelayo, itholakala ekusabalaliseni kwe-Apache Ignite kumkhombandlela we-libs/ongakukhetha futhi ayifakiwe kumzila wekilasi. Ungakwazi ukumane unyuse uhla lwemibhalo ukhuphuke ileveli eyodwa uye ku-libs bese kuthi lapho ulisebenzisa nge-ignite.sh luzovulwa ngokuzenzakalelayo.
• Ukuphikelela kufanele kunikwe amandla (Kunikwe amandla nge DataRegionConfiguration.setPersistenceEnabled(true)).
• Imodi yokucindezela kufanele isethwe kusetshenziswa indlela DataStorageConfiguration.setWalPageCompression(), ukucindezelwa kukhutshaziwe ngokuzenzakalelayo (Imodi EKHUBAZIWEYO).
• Ngokuzithandela, ungasetha izinga lokucindezela usebenzisa indlela DataStorageConfiguration.setWalPageCompression(), bona i-javadoc yendlela yamanani avumelekile kumodi ngayinye.

isiphetho

Izindlela zokucindezelwa kwedatha ezicatshangelwayo ku-Apache Ignite zingasetshenziswa ngokuzimela, kodwa noma iyiphi inhlanganisela yazo iyamukeleka. Ukuqonda ukuthi zisebenza kanjani kuzokuvumela ukuthi unqume ukuthi ziyilungele kangakanani imisebenzi yakho endaweni okuyo nokuthi yini okuzodingeka uyidele lapho uzisebenzisa. Ukucindezelwa kwekhasi lediski kuklanyelwe ukucindezela isitoreji esikhulu futhi kunganikeza isilinganiso sokucindezela okumaphakathi. Ukucindezelwa kwesifinyezo sekhasi le-WAL kuzonikeza izinga elimaphakathi lokuminyanisa amafayela e-WAL, futhi cishe kuzothuthukisa nokusebenza. Ukuhlanganiswa kwe-WAL ngeke kube nomphumela omuhle ekusebenzeni, kodwa kuzonciphisa usayizi wamafayela we-WAL ngangokunokwenzeka ngokukhipha amarekhodi aphathekayo.

Source: www.habr.com