High util iostat

j.stalin

6/7/23, 10:01 AM

I have server with oracle db. It works on Dell Unity storage. The server has very slow disk IO. How can I fix it?

Here are some details of my server:

  
OS - OL8
 
Kernel - 5.4.17 uek
 
Storage - Dell Unity XT 880F (32 * SSD disk 1,92TB)

DB - Oracle 12.1

iostat output:

Device            r/s     w/s     rMB/s     wMB/s   rrqm/s   wrqm/s  %rrqm  %wrqm r_await w_await aqu-sz rareq-sz wareq-sz  svctm  %util
dm-2          3937.60 1732.00    148.54    110.53     3.70     0.40   0.09   0.02    1.89    7.01  16.68    38.63    65.35   0.17  98.33
dm-3            64.20 1375.50      0.25    135.57     0.00     3.00   0.00   0.22    1.38    1.45   1.34     4.02   100.92   0.64  92.29
dm-5          3941.30 1725.50    148.24    110.53     0.00     0.00   0.00   0.00    1.92    6.18  18.25    38.51    65.59   0.17  98.35
dm-7            64.30 1379.30      0.25    135.53     0.00     0.00   0.00   0.00    1.39    1.44   2.07     4.02   100.62   0.67  96.83
dm-8          3941.20 1725.50    148.23    110.53     0.00     0.00   0.00   0.00    1.93    6.19  18.27    38.51    65.59   0.17  98.35

0 + 0

linux

performance

storage

iostat

Score:0

Server

j.stalin

6/13/23, 8:27 AM

any ideas guys? here is fio output:

Disk stats (read/write):
    dm-8: ios=210012/241362, merge=0/0, ticks=132262/87248, in_queue=219510, util=90.87%, aggrios=210027/241509, aggrmerge=0/0, aggrticks=131540/86615, aggrin_queue=218155, aggrutil=90.87%
    dm-5: ios=210027/241509, merge=0/0, ticks=131540/86615, in_queue=218155, util=90.87%, aggrios=210024/241426, aggrmerge=3/82, aggrticks=132557/89609, aggrin_queue=25556, aggrutil=90.79%
    dm-2: ios=210024/241426, merge=3/82, ticks=132557/89609, in_queue=25556, util=90.79%, aggrios=26253/30178, aggrmerge=0/0, aggrticks=15836/10594, aggrin_queue=3100, aggrutil=78.97%

0 + 0

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: High util iostat

TH: iostat ที่มีประโยชน์สูง

RO: High util iostat

RU: Высокая полезность

VI: iostat sử dụng cao

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