Re: conntrackd: questions about the new alarm implementation

[Pablo Neira Ayuso <pablo@netfilter.org>]

Max Kellermann wrote:
> I have had a look at your new alarm.c.  I have a few questions about
> it:
> 
> - Please explain why you now have 2048 (!) alarm queues, where the
>   correct one is determined by hashing the alarm struct.  I fail to
>   imagine how this hashing might be useful.  I can only see that it
>   makes the code more complex and 2048 times slower - except for
>   add_alarm(), which becomes a little bit faster, but there are only
>   few add_alarm() invocations compared with get_next_alarm_run() and
>   do_alarm_run().

This assumption is true for stats and sync-ftfw. However, it's not for
the sync-alarm implementation. The previous approach sucks up CPU in
add_alarm() with 25000 connections. Current the benchmarks report
smoother results.

-- 
"Los honestos son inadaptados sociales" -- Les Luthiers