From: Stefan Hajnoczi <stefanha@gmail.com>
To: "Denis V. Lunev" <den@openvz.org>
Cc: Kevin Wolf <kwolf@redhat.com>,
Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>,
qemu-devel@nongnu.org, qemu-block@nongnu.org,
Max Reitz <mreitz@redhat.com>
Subject: Re: [PATCH 0/2] block: add logging facility for long standing IO requests
Date: Wed, 29 Jul 2020 11:31:39 +0100 [thread overview]
Message-ID: <20200729103139.GC37763@stefanha-x1.localdomain> (raw)
In-Reply-To: <20200710172711.8059-1-den@openvz.org>
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On Fri, Jul 10, 2020 at 08:27:09PM +0300, Denis V. Lunev wrote:
> There are severe delays with IO requests processing if QEMU is running in
> virtual machine or over software defined storage. Such delays potentially
> results in unpredictable guest behavior. For example, guests over IDE or
> SATA drive could remount filesystem read-only if write is performed
> longer than 10 seconds.
>
> Such reports are very complex to process. Some good starting point for this
> seems quite reasonable. This patch provides one. It adds logging of such
> potentially dangerous long IO operations.
>
> Signed-off-by: Denis V. Lunev <den@openvz.org>
> CC: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> CC: Kevin Wolf <kwolf@redhat.com>
> CC: Max Reitz <mreitz@redhat.com>
This looks useful. It is indeed hard to diagnose soft lockups, I/O
timeouts, etc inside the guest :). QEMU should print more info. Thanks
for doing this!
Stefan
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next prev parent reply other threads:[~2020-07-29 10:32 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-10 17:27 [PATCH 0/2] block: add logging facility for long standing IO requests Denis V. Lunev
2020-07-10 17:27 ` [PATCH 1/2] block/block-backend: add converter from BlockAcctStats to BlockBackend Denis V. Lunev
2020-07-11 10:05 ` Vladimir Sementsov-Ogievskiy
2020-07-10 17:27 ` [PATCH 2/2] block: add logging facility for long standing IO requests Denis V. Lunev
2020-07-11 10:31 ` Vladimir Sementsov-Ogievskiy
2020-07-29 10:30 ` Stefan Hajnoczi
2020-07-29 11:06 ` Denis V. Lunev
2020-07-31 10:23 ` Stefan Hajnoczi
2020-07-29 10:31 ` Stefan Hajnoczi [this message]
2020-07-31 10:25 ` [PATCH 0/2] " Stefan Hajnoczi
2020-07-31 10:31 ` Denis V. Lunev
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