Hi everyone, I'd like to allow VDSM to change the verbosity of its loggers at runtime, without restarting the daemon. Doing so, we could make the default silent, and we'll also offer a convenient way for users to enable/disable debug log. When something has to be debugged or better understood, one can temporarily increase verbosiness, and then restore the normal level, with minimal service disruption (= no vdsmd restart). Currently vdsm uses the standard 'logging' module, which, to best of my knowledge, allows to tune levels at runtime since forever. So, the main concern is the interface. I see these options, from the one I like the most to the one I like the least: 1. add a inotify helper/trigger, just reload the config file when changed. Seems safe and convenient, but will lead to a "complex" patch. 2. just add a new verb to be used by Engine/vdsClient/whatever. Tuning log levels is not more dangerous than a truckload of verbs we already expose 3. build on the manhole integration (https://gerrit.ovirt.org/#/c/32147/). 4. use signals (SIGUSR? SIGHUP?) Thoughts welcome -- Francesco Romani RedHat Engineering Virtualization R & D Phone: 8261328 IRC: fromani
----- Original Message -----
From: "Francesco Romani" <fromani@redhat.com> To: devel@ovirt.org Sent: Wednesday, March 4, 2015 10:21:00 AM Subject: [ovirt-devel] [VDSM] dynamic tuning of logging
Hi everyone,
I'd like to allow VDSM to change the verbosity of its loggers at runtime, without restarting the daemon.
Doing so, we could make the default silent, and we'll also offer a convenient way for users to enable/disable debug log. When something has to be debugged or better understood, one can temporarily increase verbosiness, and then restore the normal level, with minimal service disruption (= no vdsmd restart).
Currently vdsm uses the standard 'logging' module, which, to best of my knowledge, allows to tune levels at runtime since forever.
So, the main concern is the interface. I see these options, from the one I like the most to the one I like the least:
1. add a inotify helper/trigger, just reload the config file when changed. Seems safe and convenient, but will lead to a "complex" patch.
2. just add a new verb to be used by Engine/vdsClient/whatever. Tuning log levels is not more dangerous than a truckload of verbs we already expose
vdsClient -s 0 setLogLevel 20
3. build on the manhole integration (https://gerrit.ovirt.org/#/c/32147/).
4. use signals (SIGUSR? SIGHUP?)
Thoughts welcome
-- Francesco Romani RedHat Engineering Virtualization R & D Phone: 8261328 IRC: fromani _______________________________________________ Devel mailing list Devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/devel
----- Original Message -----
From: "Nir Soffer" <nsoffer@redhat.com> To: "Francesco Romani" <fromani@redhat.com> Cc: devel@ovirt.org Sent: Wednesday, March 4, 2015 6:24:42 PM Subject: Re: [ovirt-devel] [VDSM] dynamic tuning of logging
2. just add a new verb to be used by Engine/vdsClient/whatever. Tuning log levels is not more dangerous than a truckload of verbs we already expose
vdsClient -s 0 setLogLevel 20
Nice! Next time I'll do a bit more research :) Thanks, -- Francesco Romani RedHat Engineering Virtualization R & D Phone: 8261328 IRC: fromani
On 04/03/15 18:24, Nir Soffer wrote:
vdsClient -s 0 setLogLevel 20
Does this survive a restart of the vdsm service? -- Mit freundlichen Grüßen / Regards Sven Kieske Systemadministrator Mittwald CM Service GmbH & Co. KG Königsberger Straße 6 32339 Espelkamp T: +49-5772-293-100 F: +49-5772-293-333 https://www.mittwald.de Geschäftsführer: Robert Meyer St.Nr.: 331/5721/1033, USt-IdNr.: DE814773217, HRA 6640, AG Bad Oeynhausen Komplementärin: Robert Meyer Verwaltungs GmbH, HRB 13260, AG Bad Oeynhausen
participants (4)
-
Dan Kenigsberg -
Francesco Romani -
Nir Soffer -
Sven Kieske