tuning for maximum dhcp performance

[Brian Raaen]

I'll have to dig through my bookmarks, but I did some research on filesystems 
a little while back.  Ext3 would be the worst for speed.  I know that reiser 
in know for high speed on small files, but forget about internal changes on 
an existing file.  XFS does hold some changes to RAM before committing them 
to the drive, but the impact of that seems minimal in your case.  Each system 
has its trade offs, and personally I like XFS (for an audio file server) and 
JFS for some of my uses.  I'll dig up my bookmarks when I can and forward the 
links to you.  Sorry about not seeing the part that you had tried a 
ramdisk... brain dump.  If I recall though JFS was the best for constantly 
changing files. 



-- 
Brian Raaen
Network Engineer
braaen at zcorum.com
Tel 678-507-5000x5574


On Friday 25 April 2008, Dan wrote:
> 
> My original post comments on the performance gains of a ramdrive, but I'd 
> be much more likely to just remove the per-lease fsync and keep it on the 
> generator-backed, ups-backed, battery-backed raid10 which gives me almost 
> the same performance, but without as much exposure:
> 
>   80 clients/sec - raid10
> 420 clients/sec - raid10 no fsync
> 480 clients/sec - ramdisk
> 
> Rsycning a fairly large dhcpd.leases periodically leaves a lot of room for 
> lost information.
> 
> I would still prefer keeping the fsync, although I'd be curious to know 
> how many people are running systems without the fsync or on a ramdrive.
> 
> 
> On Fri, 25 Apr 2008, Brian Raaen wrote:
> 
> > Dear Dan,
> > 	As far as the filesystem goes, for the ultimate in performance you might 
want
> > to mount /etc/dhcpd (or wherever your leases file is) to a partition in 
your
> > RAM.  Your could rsync this folder every few minutes/hours to back it up
> > depending on your needs.  That would keep you from being harddrive bound.
> >
> >
> >
> 
>
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