Ndi positi yaifupi iyi ndikufuna kuchotsa kusamvetsetsana kumodzi kokhudzana ndi kusanthula kwa nkhokwe za AWR zomwe zikuyenda pa Oracle Exadata. Kwa zaka pafupifupi 10, ndakhala ndikuyang'anizana ndi funso: kodi thandizo la Exadata Software ndi chiyani? Kapena kugwiritsa ntchito mawu omwe angopangidwa kumene: kodi "katswiri" ndi ntchito ya nkhokwe inayake?
Nthawi zambiri funso lolondola ili, m'malingaliro mwanga, limayankhidwa molakwika potengera ziwerengero za AWR. Imapereka njira yodikirira dongosolo, yomwe imagwiritsa ntchito nthawi yoyankha monga kuchuluka kwa nthawi yogwira ntchito ya ma processor (DB CPUs) ndi nthawi yodikirira yamagulu osiyanasiyana.
Pakubwera kwa Exadata, zoyembekeza zadongosolo zokhudzana ndi ntchito ya Exadata Software zidawonekera mu ziwerengero za AWR. Monga lamulo, mayina amadikirira otere amayamba ndi mawu oti "selo" (seva ya Exadata Storage imatchedwa cell), yomwe ambiri amadikirira ndi mayina oti "cell smart table scan", "cell multiblock physical read" ndi "cell single block physical read".
Nthawi zambiri, gawo la Exadata yotereyi amadikirira mu nthawi yonse yoyankhira ndi yaying'ono, chifukwa chake samagwera mu gawo la Top10 Foreground Events by Total Wait Time gawo (pankhaniyi, muyenera kuwayang'ana pa Kudikirira Kutsogolo. Gawo la zochitika). Movutikira kwambiri, tapeza chitsanzo cha AWR tsiku lililonse kuchokera kwa makasitomala athu, momwe ziyembekezo za Exadata zidaphatikizidwa mu gawo la Top10 ndipo zonse zidafika pafupifupi 5%:
chochitika
Kudikirira
Nthawi Yodikirira Yonse (mphindikati)
Avg Dikirani
% DB nthawi
Dikirani Kalasi
DB CPU
115.2K
70.4
SQL* Zambiri zambiri kuchokera ku dblink
670,196
5471.5
8.16ms
3.3
Network
cell single block physical kuwerenga
5,661,452
3827.6
Kutha
2.3
Wogwiritsa ntchito I/O
Gwirizanitsani kubweza kwa ASM
4,350,012
3481.3
Kutha
2.1
Zina
cell multiblock kuwerenga thupi
759,885
2252
2.96ms
1.4
Wogwiritsa ntchito I/O
kuwerenga njira yolunjika
374,368
1811.3
4.84ms
1.1
Wogwiritsa ntchito I/O
SQL* Net uthenga kuchokera ku dblink
7,983
1725
216.08ms
1.1
Network
cell smart table scan
1,007,520
1260.7
1.25ms
0.8
Wogwiritsa ntchito I/O
njira yolunjika yowerengera temp
520,211
808.4
1.55ms
0.5
Wogwiritsa ntchito I/O
enq: TM - kukangana
652
795.8
1220.55ms
0.5
ntchito
Zotsatira zotsatirazi nthawi zambiri zimatengedwa kuchokera ku ziwerengero za AWR:
1. Kupereka kwamatsenga a Exadata ku ntchito ya database sikwapamwamba - sikudutsa 5%, ndipo database "ikuwonjezera" molakwika.
2. Ngati deta yotereyi imasamutsidwa kuchokera ku Exadata kupita ku zomangamanga za "server + array", ndiye kuti ntchitoyo sidzasintha kwambiri. Chifukwa ngakhale gululi likuwoneka kuti likuyenda pang'onopang'ono katatu kuposa njira yosungira ya Exadata (yomwe sizingatheke kumagulu onse amakono a Flash), ndiye kuchulukitsa 5% ndi atatu timapeza kuwonjezeka kwa gawo la I/O kudikirira mpaka 15% - database idzapulumuka izi!
Malingaliro onsewa ndi olakwika, komanso amasokoneza kumvetsetsa kwa lingaliro la Exadata Software. Exadata sikuti imangopereka I/O yachangu, imagwira ntchito mosiyana poyerekeza ndi ma seva apamwamba + omanga. Ngati ntchito ya database ndi "yosinthidwa", ndiye kuti malingaliro a SQL amasamutsidwa kumalo osungira. Ma seva osungira, chifukwa cha njira zingapo zapadera (makamaka Exadata Storage Indexes, koma osati kokha), pezani deta yofunikira okha ndikutumiza DB ku maseva. Amachita izi bwino kwambiri, kotero gawo la Exadata lomwe limadikirira mu nthawi yonse yoyankha ndilochepa.
Kodi gawoli lisintha bwanji kunja kwa Exadata? Kodi izi zidzakhudza bwanji magwiridwe antchito a database yonse? Kuyesa kuyankha bwino mafunso awa. Mwachitsanzo, kudikirira "kujambula kwa tebulo lanzeru" kunja kwa Exadata kumatha kukhala Table Full Scan yolemera kotero kuti I/O imatenga nthawi yonse yoyankha ndipo magwiridwe antchito amatsika kwambiri. Ndicho chifukwa chake n'kulakwa, pofufuza AWR, kulingalira chiwerengero chonse cha zomwe Exadata amayembekeza monga chopereka chamatsenga ake pakuchita, komanso makamaka kugwiritsa ntchito chiwerengerochi kulosera ntchito kunja kwa Exadata. Kuti mumvetse momwe ntchito ya database ilili "ndendende", muyenera kuphunzira ziwerengero za AWR za gawo la "Instance Activity Stats" (pali ziwerengero zambiri zokhala ndi mayina ofotokozera) ndikuziyerekeza wina ndi mnzake.
Ndipo kuti mumvetsetse momwe nkhokwe kunja kwa Exadata ingamve, ndikwabwino kupanga chojambula cha database kuchokera pa zosunga zobwezeretsera pamamangidwe omwe mukufuna ndikuwunika momwe fanizoli likulemedwa. Monga lamulo, eni eni a Exadata ali ndi mwayi umenewu.
Author: Alexey Struchenko, wamkulu wa dipatimenti ya database ya Jet Infosystems
Source: www.habr.com