problems with samba and Perc/2 RAID

[David Collier-Brown]

John (Shiro) saith:
> We recently acquired a Dell PowerEdge 4300 with two PIII 500
> Xeons and half a gig of RAM, running RedHat 6.1 out of the box.  In
> addition, it has a PERC2/SC Single Channel RAID card for six 18GB LVD
> SCSI drives.

> The problem is that, while we're not doing anything fancy with
> samba, basic file share stuff, the load seems to spike whenever writes
> are done.  When doing a large file copy, the load will steadily rise to
> about 7 or 8, and then the share stops responding, killing any file
> copy taking place.
> It's not the RAID that's causing the problem per se; when I do
> a large file copy on the server, the copy works just fine without a
> load spike taking place.

	Ok, somethin's wierd: Samba just does open, read/write, close
	when it's doing i/o. It **should** be indistinguishable from
	a local copy.

	Try a local copy to /dev/null and  a samba copy to /dev/null,
	and see if the samba load leaps up.  If so, it's related to
	the network rather than the disk.

	Run trace/truss/strace on the samba process and email me the
	results: I'll snip out the interesting parts and post them here.
	(But I'm only in town until thursday)

--dave
-- 
David Collier-Brown,  | Always do right. This will gratify some people
185 Ellerslie Ave.,   | and astonish the rest.        -- Mark Twain
Willowdale, Ontario   | //www.oreilly.com/catalog/samba/author.html
Work: (905) 415-2849 Home: (416) 223-8968 Email: davecb at canada.sun.com