From: Kevin Wolf <kwolf@redhat.com>
To: Hanna Czenczek <hreitz@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>,
qemu-block@nongnu.org, qemu-devel@nongnu.org,
John Snow <jsnow@redhat.com>, "Denis V . Lunev" <den@openvz.org>,
Eric Blake <eblake@redhat.com>,
Markus Armbruster <armbru@redhat.com>
Subject: Re: [PATCH 0/9] block: BLOCK_IO_DELAY event
Date: Wed, 23 Sep 2026 16:50:00 +0200 [thread overview]
Message-ID: <arPnGOoK2CvIR5Sq@redhat.com> (raw)
In-Reply-To: <6a6a77e9-8acb-4312-aa38-e06f81ac882e@redhat.com>
Am 23.09.2026 um 12:48 hat Hanna Czenczek geschrieben:
> > > > When an I/O request hangs for a long time, the management tool will be
> > > > unable to detect that the threshold has been exceeded in a timely
> > > > manner.
> > > Yes. But why would that be a real problem?
> > >
> > > Given the request so far is only to notify users of their storage block
> > > showing problematic latencies at all, there is no need to provide the alerts
> > > in actual real time.
> > What does the current approach solve that is not already possible with
> > the block latency histogram?
>
> See what I linked above. Apparently having to repeatedly query the histogram
> repeatedly is not deemed nice enough.
It's the difference between an event and active polling. I would agree
that active polling isn't the right answer in most cases.
Kevin
next prev parent reply other threads:[~2026-09-23 14:51 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-31 13:51 [PATCH 0/9] block: BLOCK_IO_DELAY event Hanna Czenczek
2026-08-31 13:51 ` [PATCH 1/9] block/accounting: Add offset to BlockAcctCookie Hanna Czenczek
2026-09-07 10:05 ` Jesper Wendel Devantier
2026-08-31 13:51 ` [PATCH 2/9] qapi/block: Add IoAccountingOperation enum Hanna Czenczek
2026-09-03 14:32 ` Markus Armbruster
2026-09-16 8:09 ` Hanna Czenczek
2026-08-31 13:51 ` [PATCH 3/9] qapi/block: Add BLOCK_IO_DELAY event Hanna Czenczek
2026-09-03 14:36 ` Markus Armbruster
2026-09-16 8:08 ` Hanna Czenczek
2026-09-16 9:57 ` Markus Armbruster
2026-08-31 13:52 ` [PATCH 4/9] block-backend: Public blk_get_attached_dev_path() Hanna Czenczek
2026-08-31 13:52 ` [PATCH 5/9] block/accounting: Add BB field to latency checker Hanna Czenczek
2026-09-22 12:14 ` Kevin Wolf
2026-09-23 11:05 ` Hanna Czenczek
2026-08-31 13:52 ` [PATCH 6/9] block/accounting: Emit BLOCK_IO_DELAY event Hanna Czenczek
2026-09-03 14:23 ` Stefan Hajnoczi
2026-09-16 8:14 ` Hanna Czenczek
2026-09-16 12:04 ` Hanna Czenczek
2026-09-21 20:48 ` Stefan Hajnoczi
2026-09-23 10:45 ` Hanna Czenczek
2026-09-22 12:44 ` Kevin Wolf
2026-09-23 11:11 ` Hanna Czenczek
2026-08-31 13:52 ` [PATCH 7/9] block: Add delay-alert-ms property Hanna Czenczek
2026-09-03 14:30 ` Stefan Hajnoczi
2026-09-16 8:17 ` Hanna Czenczek
2026-09-22 12:51 ` Kevin Wolf
2026-08-31 13:52 ` [PATCH 8/9] block/accounting: Move latency_ns override down Hanna Czenczek
2026-09-03 15:08 ` Stefan Hajnoczi
2026-09-16 8:21 ` Hanna Czenczek
2026-09-21 20:42 ` Stefan Hajnoczi
2026-09-22 13:03 ` Kevin Wolf
2026-09-22 13:44 ` Alberto Garcia
2026-09-22 13:52 ` Kevin Wolf
2026-09-23 10:50 ` Hanna Czenczek
2026-08-31 13:52 ` [PATCH 9/9] iotests: Add delay-alert test Hanna Czenczek
2026-09-03 15:16 ` Stefan Hajnoczi
2026-09-03 14:08 ` [PATCH 0/9] block: BLOCK_IO_DELAY event Stefan Hajnoczi
2026-09-16 8:04 ` Hanna Czenczek
2026-09-21 20:41 ` Stefan Hajnoczi
2026-09-22 13:31 ` Kevin Wolf
2026-09-22 17:18 ` Stefan Hajnoczi
2026-09-23 10:52 ` Hanna Czenczek
2026-09-24 14:51 ` Stefan Hajnoczi
2026-09-23 10:48 ` Hanna Czenczek
2026-09-23 14:50 ` Kevin Wolf [this message]
2026-09-24 15:17 ` Stefan Hajnoczi
2026-09-24 18:31 ` Kevin Wolf
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=arPnGOoK2CvIR5Sq@redhat.com \
--to=kwolf@redhat.com \
--cc=armbru@redhat.com \
--cc=den@openvz.org \
--cc=eblake@redhat.com \
--cc=hreitz@redhat.com \
--cc=jsnow@redhat.com \
--cc=qemu-block@nongnu.org \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.