From: Stefan Hajnoczi <stefanha@redhat.com>
To: Markus Armbruster <armbru@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>,
Pavel Butsykin <pbutsykin@virtuozzo.com>,
qemu-devel@nongnu.org, Luiz Capitulino <lcapitulino@redhat.com>,
"Denis V. Lunev" <den@openvz.org>
Subject: Re: [Qemu-devel] What's the intended use of log.h logging? (was: [PATCH 2/3] log: report hmp/qmp command and qmp event)
Date: Wed, 21 Oct 2015 11:41:44 +0100 [thread overview]
Message-ID: <20151021104144.GC13408@stefanha-thinkpad.redhat.com> (raw)
In-Reply-To: <87oafzdmck.fsf_-_@blackfin.pond.sub.org>
Two useful aspects for observability:
1. Logging
Error messages, rate-limited warnings, and important troubleshooting
information for users.
Audience: Users, system administrators, developers
2. Tracing
Internal state changes and events for performance analysis.
Audience: Developers
DPRINTF() falls under both #1 and #2. Care needs to be taken to
separate the logging from the tracing when converting DPRINTF().
Side note: we don't have effect "once only" or rate-limiting built into
error_report(). Guest-triggerable errors or warnings should be limited
to prevent log flooding.
It would be nice to unify TCG's "qemu log" and error_report() into a
single logging mechanism that is thread-safe and has rate-limiting.
Stefan
next prev parent reply other threads:[~2015-10-21 10:41 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-15 7:30 [Qemu-devel] [PATCH 0/3] QEMU logging improvements Denis V. Lunev
2015-10-15 7:30 ` [Qemu-devel] [PATCH 1/3] log: improve performance of qemu_log and qemu_log_mask if disabled Denis V. Lunev
2015-10-15 17:23 ` Alex Bennée
2015-10-15 17:40 ` Denis V. Lunev
2015-10-15 18:36 ` Alex Bennée
2015-10-16 7:17 ` Markus Armbruster
2015-10-16 7:45 ` Denis V. Lunev
2015-10-16 11:02 ` Markus Armbruster
2015-10-16 11:08 ` Denis V. Lunev
2015-10-15 7:30 ` [Qemu-devel] [PATCH 2/3] log: report hmp/qmp command and qmp event Denis V. Lunev
2015-10-16 7:34 ` Markus Armbruster
2015-10-16 9:51 ` Pavel Butsykin
2015-10-16 12:35 ` Markus Armbruster
2015-10-16 12:33 ` [Qemu-devel] What's the intended use of log.h logging? (was: [PATCH 2/3] log: report hmp/qmp command and qmp event) Markus Armbruster
2015-10-16 12:48 ` [Qemu-devel] What's the intended use of log.h logging? Paolo Bonzini
2015-10-16 12:54 ` Peter Maydell
2015-10-16 13:00 ` Paolo Bonzini
2015-10-16 13:38 ` Denis V. Lunev
2015-10-16 13:26 ` Daniel P. Berrange
2015-10-16 13:29 ` Peter Maydell
2015-10-16 13:30 ` Paolo Bonzini
2015-10-16 13:36 ` Peter Maydell
2015-10-16 14:17 ` Paolo Bonzini
2015-10-16 14:31 ` Peter Maydell
2015-10-16 15:27 ` Paolo Bonzini
2015-10-19 13:17 ` Markus Armbruster
2015-10-19 13:19 ` Paolo Bonzini
2015-10-19 13:54 ` Peter Maydell
2015-10-16 12:51 ` [Qemu-devel] What's the intended use of log.h logging? (was: [PATCH 2/3] log: report hmp/qmp command and qmp event) Peter Maydell
2015-10-19 14:29 ` [Qemu-devel] What's the intended use of log.h logging? Markus Armbruster
2015-10-19 14:41 ` Peter Maydell
2015-10-19 16:57 ` Dr. David Alan Gilbert
2015-10-19 17:02 ` Dr. David Alan Gilbert
2015-10-20 13:11 ` Kevin Wolf
2015-10-16 14:36 ` [Qemu-devel] What's the intended use of log.h logging? (was: [PATCH 2/3] log: report hmp/qmp command and qmp event) Alex Bennée
2015-10-19 14:52 ` [Qemu-devel] What's the intended use of log.h logging? Markus Armbruster
2015-10-19 14:57 ` Peter Maydell
2015-10-21 10:41 ` Stefan Hajnoczi [this message]
2015-10-21 11:10 ` Denis V. Lunev
2015-10-21 12:22 ` [Qemu-devel] What's the intended use of log.h logging? (was: [PATCH 2/3] log: report hmp/qmp command and qmp event) Peter Maydell
2015-10-22 12:26 ` Stefan Hajnoczi
2015-10-22 13:05 ` [Qemu-devel] What's the intended use of log.h logging? Paolo Bonzini
2015-10-15 7:30 ` [Qemu-devel] [PATCH 3/3] log: adds a timestamp to each log entry Denis V. Lunev
2015-10-16 7:49 ` Markus Armbruster
2015-10-16 9:55 ` Pavel Butsykin
2015-10-16 11:33 ` Markus Armbruster
2015-10-15 14:49 ` [Qemu-devel] [PATCH 0/3] QEMU logging improvements Kashyap Chamarthy
2015-10-15 15:18 ` Pavel Butsykin
2015-10-15 16:02 ` Kashyap Chamarthy
2015-10-26 9:16 ` Markus Armbruster
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