With this short post, I would like to dispel one misunderstanding related to the AWR analysis of databases running on Oracle Exadata. For almost 10 years, I have been constantly confronted with the question: What is the contribution of Exadata Software to productivity? Or with the use of newly formed words: to what extent does the work of this or that database go?
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Exadata- , Top10 Foreground Events by Total Wait Time ( Foreground Wait Events). AWR, Exadata- Top10 5%:
Event | Waits | Total Wait Time (sec) | Avg Wait | % DB time | Wait Class |
DB CPU |
| 115.2K |
| 70.4 |
|
SQL*Net more data from dblink | 670,196 | 5471.5 | 8.16ms | 3.3 | Network |
cell single block physical read | 5,661,452 | 3827.6 | 676.07us | 2.3 | User I/O |
Sync ASM rebalance | 4,350,012 | 3481.3 | 800.30us | 2.1 | Other |
cell multiblock physical read | 759,885 | 2252 | 2.96ms | 1.4 | User I/O |
direct path read | 374,368 | 1811.3 | 4.84ms | 1.1 | User I/O |
SQL*Net message from dblink | 7,983 | 1725 | 216.08ms | 1.1 | Network |
cell smart table scan | 1,007,520 | 1260.7 | 1.25ms | 0.8 | User I/O |
direct path read temp | 520,211 | 808.4 | 1.55ms | 0.5 | User I/O |
enq: TM - contention | 652 | 795.8 | 1220.55ms | 0.5 | Application |
AWR :
1. Exadata — 5 %, «» .
2. Exadata « + », . Exadata ( All Flash ), 5% - 15% — !
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