Re: [PATCH 2.6.25-4] getdelays.c: signal handling for log rotation

[Andi Kleen <andi@firstfloor.org>]

Scott Wiersdorf wrote:
> On Fri, Jun 06, 2008 at 03:59:09PM +0200, Andi Kleen wrote:
>> Scott Wiersdorf <scott@perlcode.org> writes:
>>
>>> This adds a USR1 signal handler to getdelays.c, which causes getdelays
>>> to close its logfile and reopen it (if '-w logfile' is
>>> specified). This is useful in situations when getdelays is running for
>>> a long time (i.e, the log file growing) and you need to rotate the
>>> logs but don't want to lose any log data.
>> You could do the same by sending SIGSTOP; copy file; truncate file; SIGCONT
> 
> I believe it, but you can miss a lot of important stuff between STOP
> and CONT, especially on a busy system.

Do you have data on that or are you guessing?

I suspect the later, I'm sceptical of your claim. A lot of events
fit into the netlink socket buffer.

-Andi