Looks like I replied only on Thorsten insteading of replying to all so moving the discussion to the wider thread for better visibility.
---------- Forwarded message --------- From: Thorsten Leemhuis regressions@leemhuis.info Date: Tue, 20 Sept 2022 at 14:31 Subject: Re: Ext4: Buffered random writes performance regression with dioread_nolock enabled To: hazem ahmed mohamed hazem.ahmed.abuelfotoh@gmail.com
On 20.09.22 15:21, hazem ahmed mohamed wrote:
Thanks Thorsten, I am surprised that we merged this commit while it has been showing regression since Day-0, unless there is an objection I will submit a revert patch until we know what's going on here.
Please keep replies online, then others can learn from the conversation and weight in. In this particular case I'd explained that a quick revert after all this time is likely a bad thing, as there is always a risk that is creates regressions of its own. :-/
Ciao, Thorsten
On 19.09.22 17:18, hazem ahmed mohamed wrote:
I am sending this e-mail to report a performance regression that’s caused by commit 244adf6426(ext4: make dioread_nolock the default) , I am listing the performance regression symptoms below & our analysis for the reported regression.
FWIW, that patch went into v5.6-rc1~113^2~12
And BTW: it seems 0-day back then noticed that 244adf6426 caused a performance regression as well, but it seems that was ignored: https://lore.kernel.org/all/20201024120829.GK31092@shao2-debian/
Anyway, now to the main reason why I write this mail:
[TLDR: I'm adding this regression report to the list of tracked regressions; all text from me you find below is based on a few templates paragraphs you might have encountered already already in similar form.]
Thanks for the report. To be sure below issue doesn't fall through the cracks unnoticed, I'm adding it to regzbot, my Linux kernel regression tracking bot:
#regzbot ^introduced 244adf6426 #regzbot ignore-activity
This isn't a regression? This issue or a fix for it are already discussed somewhere else? It was fixed already? You want to clarify when the regression started to happen? Or point out I got the title or something else totally wrong? Then just reply -- ideally with also telling regzbot about it, as explained here: https://linux-regtracking.leemhuis.info/tracked-regression/
Reminder for developers: When fixing the issue, add 'Link:' tags pointing to the report (the mail this one replies to), as explained for in the Linux kernel's documentation; the webpage mention at the end of the last para explains why this is important for tracked regressions.
Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
P.S.: As the Linux kernel's regression tracker I deal with a lot of reports and sometimes miss something important when writing mails like this. If that's the case here, don't hesitate to tell me in a public reply, it's in everyone's interest to set the public record straight.