[CentOS] Calling All FS Fanatics

[Les Mikesell]

On Wed, 2006-10-04 at 11:29 -0400, Joshua Baker-LePain wrote:

> > Does anyone have any bonnie++ results for Linux software RAID 5?  I know
> > software RAID 5 does not really lend itself to a performant software
> > implementation, but the results would be interesting to see, none the
> > less.
> 
> Actually, md is a *very* good performer (although I don't have any 
> benchmarks on hand at the moment).  The reason I stick with hardware RAID 
> is that md doesn't handle hot swapping all that well.  Not taking systems 
> down to replace bad disks is a Good Thing.

Now that disks are not so expensive you have to look at the difference
in performance with raid 5 vs. raid 1 or 0+1.  Raid5 essential ties
all of the disk heads together and seek time is usually the bottleneck
unless you have a single process accessing a huge file.  Of course these
days you can also throw RAM at the problem and at least avoid the seek
to read the block that you are going to partially overwrite by having it
already in the buffers.

-- 
  Les Mikesell
   lesmikesell at gmail.com