Re: Log rotation issue with runit

[Guillermo <gdiazhartusch@gmail.com>]

El mar., 25 dic. 2018 a las 10:39, Dmitry Bogatov escribió:
>
> Hello!
>
> I am Debian maintainer of `runit' supervision suite. Recently, I
> received bug report [^1] about stray .u logfiles. After some
> investigation I found code, that caused issue, but it seems that it was
> written with some purpose, yet I fail to understand that purpose.
>
> Author Gerrit Pape directed me here. Any clarification would be welcome!
> Please keep bug in thread.
>
> [^1] https://bugs.debian.org/916230

It was likely written on purpose. A 'current' file that doesn't have
the execute by owner permission set is not considered to completely
processed, and becomes a .u file instead of being appended to. As has
been said, it can happen if svlogd does not exit cleanly. Although it
doesn't seem to be mentioned in svlogd's man page, this comes from
daemontools' multilog program, which inspired svlogd:

* https://cr.yp.to/daemontools/multilog.html (section "Automatically
rotated logs")

On the other hand, it seems to me that the patch used for resolution
of bug #878476 prevents all .u files from being deleted, so they would
indeed accumulate indefinitely. Both .u and .s files are supposed to
be deleted when they are the oldest file in the logging directory, to
honor 'u' lines in 'config' files, and this is only a problem when the
one about to be fed to a processor happens to be the one chosen for
deletion because of a wonky clock. This issue was brought up earlier
in this mailing list, and a different patch was suggested:

* https://www.mail-archive.com/supervision@list.skarnet.org/msg00667.html

This one seems to do the right check, maybe it should have been applied instead?



G.