Re: Preliminary version of s6-rc available

From: Guillermo <gdiazhartusch_at_gmail.com>
Date: Tue, 25 Aug 2015 14:01:40 -0300

2015-08-25 11:01 GMT-03:00 Laurent Bercot:
>
> I can't reproduce that one, can you please send me a "strace -vf -s 256"
> output of the s6-rc command that gives you these errors ?

OK, this is a tricky one. While looking at the strace output you asked
for, I realized myself what was going on. The s6-svc process 's6-rc
change' is spawning has options '-uwu -T 3', and my test system seems
to be slow enough (don't ask :) ) that it turns out a 3 millisecond
timeout is too small. A manual s6-svc invocation with that timeout
produces the same errors I saw when using s6-rc. And trying different
-T options, it takes over 30 ms to actually start the service I was
performing the tests with, and over 70 ms to do so without
s6-svlisten1 error messages. All my previous manual s6-svc invocations
didn't specify a timeout, so I didn't notice until now.

But the thing is, no matter what I do, strace shows the '-T 3' never
changes. Even when I explicitly put a 'timeout-up' file in the service
definition directory, either containing '0' or a long enough timeout,
or when I give s6-rc change a -t option. 's6-rc-db timeout' does show
the timeout specified by me, and correctly shows 0 when there is no
'timeout-up' file. So the real issue here appears to be that s6-svc is
always told to wait no longer than 3 ms, and, in particular, you
would't be able to make s6-rc wait forever in the "no readiness
notification" case.

Thanks,
G.
Received on Tue Aug 25 2015 - 17:01:40 UTC