Re: [pm] fix time after suspend-to-*

From: George Anzinger
Date: Wed Oct 29 2003 - 15:43:53 EST


Pavel Machek wrote:
Hi!


You are not asking userspace whether to reboot or not, and you should
not ask them about suspend, either.

OK, so how should the system behave when a real-time-like process is
running? I talked about the CD burning example. Should the kernel simply
ignore the process and suspend?


Yes.


1. Network connections must be reestablished. A userspace program can't
try to automatically reestablish a broken TCP connection for no apparent
reason. A broken TCP connection could be the cause of an overloaded or
broken server/service. If we do not inform userspace processes that the
system is going to sleep (or that the system has been brought up from
standby), they will blindly try to restore TCP connections back, even
when the remote server is broken, generating a lot of unnecesary
traffic.

gettimeofday(), if I slept for too long, oops, something strange
happened (maybe there was heavy io load and I was swapped out? or
suspend? Did machine sleep for 20 minutes in cli?) try to reconnect.

Does "gettimeofday()" have into account the effect of adjusting the time
twice a year, once to make time roll forward one hour and another one to
roll it back?


Not sure how it is supposed to work, but here I just have ntpd
step-setting by one hour...

It is really a time zone change....

--
George Anzinger george@xxxxxxxxxx
High-res-timers: http://sourceforge.net/projects/high-res-timers/
Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml

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