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I'm getting very low performance with ext4 barriers enabled (the default):

sysbench gives me with barriers on:

File operations:
    reads/s:                      55.03
    writes/s:                     36.69
    fsyncs/s:                     11.99

Throughput:
    read, MiB/s:                  0.86
    written, MiB/s:               0.57

and off:

File operations:
    reads/s:                      188684.81
    writes/s:                     125789.87
    fsyncs/s:                     3.17

Throughput:
    read, MiB/s:                  2948.20
    written, MiB/s:               1965.47

How can I troubleshoot this?

uname -a: Linux aorus 5.15.0-25-generic #25-Ubuntu SMP Wed Mar 30 15:54:22 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux.

The SSD is an HP SSD EX920 1TB.

The command line for the sysbench test was sysbench --test=fileio --file-total-size=16G --file-test-mode=rndrw --max-time=30 --max-requests=0 run.

Artefacto
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    WHat exact test you run? Similar degradation can happen with write operation with many small files where file meta info is comparable by size with data of file. And barriers make sure you have consistent filesystem. – Romeo Ninov Sep 23 '22 at 14:59
  • @RomeoNinov I've added the command line – Artefacto Sep 26 '22 at 17:05
  • Does this answer your question? [Can you help me with my capacity planning?](https://serverfault.com/questions/384686/can-you-help-me-with-my-capacity-planning) – djdomi Sep 26 '22 at 17:43
  • @djdomi I'm assuming here that the performance increasing 3500x when barriers are off is not normal. – Artefacto Sep 26 '22 at 23:46
  • @F.Hauri-GiveUpGitHub it's in the body of the question – Artefacto Sep 29 '22 at 00:57

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