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Cc: Joao Barros <joao.barros@gmail.com>, src-committers@FreeBSD.org,
	Peter Jeremy <peterjeremy@optushome.com.au>,
	"Christian S.J. Peron" <csjp@FreeBSD.org>, cvs-all@FreeBSD.org,
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Subject: Re: cvs commit: src/usr.sbin/syslogd syslogd.c
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On Fri, 31 Mar 2006, Alexander Leidinger wrote:

> Robert Watson <rwatson@FreeBSD.org> wrote:
>
>> The cost to check for free space is the cost of a fstatfs() system call on 
>> the file descriptor of the log file.  This should be handled without 
>> touching the disk, so while it's not a cheap system call compared to, say, 
>> getpid(), as it acquires locks and enters VFS, it's a lot cheaper than any 
>> disk I/O operation. Optional is good, if only because sometimes people do 
>> actually want logging to fill the disk, and that's been the behavior 
>> historically :-).
>
> Do you know if a kqueue based solution is cheaper?

I think that before solving this problem, we should establish it is one.  I'm 
not convinced it will be.

Robert N M Watson