From: Johannes Truschnigg <johannes@truschnigg.info>
To: eyal@eyal.emu.id.au
Cc: linux-raid@vger.kernel.org
Subject: Re: extremely slow writes to array [now not degraded]
Date: Mon, 13 Nov 2023 07:54:52 +0100 [thread overview]
Message-ID: <ZVHIPNwC2RKTVmok@vault.lan> (raw)
In-Reply-To: <1d0fb40a-1908-4b5e-9856-a5b79eafdc9c@eyal.emu.id.au>
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You will need to generate some kind of call stack/graph info to start making
sense of the mess your running kernel gets itself into in the scenario you
described.
I imagine that looking at `perf` (`perf top` in particular; it should suffice
to paste a few instances of its topmost lines when the involved kernel threads
are spinning) would yield some useful data to kick off a potentially
productive debate about what could actually be going on.
On Fedora, I think `sudo dnf install perf` should set up everything you need
to get you going; then, look at `sudo perf top -F 999` for a while, and let
the list know what you see. (You can use your terminal emulator's flow control
features, available via Ctrl+S to enable and Ctrl+Q to disable, to "freeze"
the output to make it easier to copy it into a clipboard buffer.)
--
with best regards:
- Johannes Truschnigg ( johannes@truschnigg.info )
www: https://johannes.truschnigg.info/
phone: +436502133337
xmpp: johannes@truschnigg.info
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next prev parent reply other threads:[~2023-11-13 6:55 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-05 23:06 extremely slow writes to degraded array eyal
2023-11-07 21:14 ` Peter Grandi
2023-11-08 1:37 ` eyal
2023-11-08 5:32 ` eyal
2023-11-08 16:50 ` Peter Grandi
2023-11-09 2:59 ` extremely slow writes to array [now not degraded] eyal
2023-11-09 13:16 ` Roger Heflin
2023-11-13 0:53 ` eyal
2023-11-13 6:54 ` Johannes Truschnigg [this message]
2023-11-13 8:06 ` eyal
2023-11-13 9:20 ` Johannes Truschnigg
2023-11-13 9:36 ` eyal
2023-11-13 9:58 ` eyal
2023-11-13 10:09 ` Johannes Truschnigg
2023-11-13 10:31 ` eyal
2023-11-13 12:26 ` Roger Heflin
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