Optimizing RCng execution speed ?

Dan Nelson dnelson at allantgroup.com
Wed Apr 14 12:44:49 PDT 2004


In the last episode (Apr 14), Tim Kientzle said:
> Colin Percival wrote:
> >Out of the total 4.88 seconds the major consumers are:
> >
> > syslogd         0.89 s
> 
>  2) What is syslogd doing for 0.89 seconds?
> 
>     I understand why mountcritlocal and fsck might take a while, but
>     syslogd doesn't strike me as an obvious slow point.  (Unless it's
>     waiting on a DNS lookup?  Can that be avoided with appropriate
>     /etc/hosts entries?)

It is logging the kernel bootup output one line at a time, fsyncing
between lines.  This can take a LONG time if you were just in
single-user mode and stored a lot of short shell lines in the kernel
buffer.  I just remove the SYNC_FILE flag from line 741.  Why is kernel
(and only kernel) log output fsynced anyway?

-- 
	Dan Nelson
	dnelson at allantgroup.com


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