One thing that will help your performance on CX700.   Be sure each RAID
group has all its disks bound to a single SP.   We had mistakenly been
alternating SPA/SPB on the theory that two paths in would increase
performance.   It turns out that the ATA drives unlike the Fibre drives
have only one connection so each time you write to the RAID group it
would have to trespass for every other write.    We modified our config
to alternate the RAID groups rather than the disks (half the RAID groups
bound to SPA, the other half bound to SPB) and have seen increased
performance on tape backups and restores since doing that.

Off topic P.S.  Does anyone but us do RAID 1_0 across buses (multiple
enclosures) on CX700?   EMC and Unisys always seem surprised when BCC
failures/replacements cause transitioning of disks even though their
internal documents now correctly state that is the expected behavior.
For over 2 years EMC tried to "troubleshoot" this transitioning and it
was only late last year we finally got someone at EMC to point out the
Primus information that shows it is designed that way.   I just wonder
if this is so atypical a configuration that it wouldn't be well known in
the organizations that support CX700?

-----Original Message-----
From: veritas-bu-bounces at mailman.eng.auburn.edu
[mailto:veritas-bu-bounces at mailman.eng.auburn.edu] On Behalf Of Justin
Piszcz
Sent: Friday, April 27, 2007 5:36 PM
To: Martin, Jonathan (Contractor)
Cc: veritas-bu at mailman.eng.auburn.edu; Navarro, Eddy A.
Subject: Re: [Veritas-bu] SATA disk backup performance

I built my own machine, with 7 raptors RAID5 sw raid I get 320-425MB/s 
read and write.  Reading from 10 of the drives at the same time, I see 
750MB/s aggregate bandwidth, but you'd ned a 10GBps to get the data off 
because 1gbps is capped at 125MB/s obviously.

Justin.

On Fri, 27 Apr 2007, Martin, Jonathan (Contractor) wrote:

> Before the "SATA Sux" crowd gets going here I'll just say this:
>
> I run 14 x 5 SATAII 500GB Disks in a Raid 5 and get better than
> 200MB/sec writes and easily drive LTO3 to 130MB/sec.  That said, I'm
> running completely different hardware, Dell server & storage.  Raid 5,
> qlogic HBAs & PERC Raid Controllers.
>
> The best thing anyone on this list ever said to me when I was in your
> shoes was forget about Netbackup.  How fast can you copy data from
point
> a to point b on your solution?  Then how fast can you multistream FTPs
> to the same solution?  Once you get those numbers into the range you
are
> expecting then you can start to performance tune NBU.  Until then,
your
> buffer settings are a waste of time.
>
> -Jonathan
>
> ________________________________
>
> From: veritas-bu-bounces at mailman.eng.auburn.edu
> [mailto:veritas-bu-bounces at mailman.eng.auburn.edu] On Behalf Of
Navarro,
> Eddy A.
> Sent: Friday, April 27, 2007 5:10 PM
> To: veritas-bu at mailman.eng.auburn.edu
> Subject: [Veritas-bu] SATA disk backup performance
>
>
>
> Gurus,
>
>
>
> I've been doing some performance testing of backing up to a Disk
Storage
> Unit of SATA disk.  We have the following:
>
>
>
> Netbackup 5.1 MP6
>
> SunFire V800 running Solaris 9 with 8GB RAM
>
> Veritas Volume Manager 4.1
>
> CX700 array with 500GB 7200rpm SATA drives
>
> Emulex LP9000 HBA
>
>
>
> I've been doing all sorts of tweaking, from adjusting the disk buffer
> files per http://seer.entsupport.symantec.com/docs/273532.htm,
cranking
> up the write cache on the CX700 to over 2GB, changing the RAID
layouts,
> but I just cannot get performance better than 15MB/s.  Surely backing
up
> to SATA can produce better results than that?
>
>
>
> Currently, I've got six 500GB LUNs each in their own 4+1 RAID group
> using RAID3.  These LUNs are then striped into a RAID0 volume using
> Veritas Volume manager (at first I tested with a striped MetaLun on
the
> array, but results were no different).
>
>
>
> As stated, I've tweaked till I'm blue in the face but I can't seem to
> squeeze anything above 15MB/s.  Any hints as to what I could be
> overlooking?  Performance is not looking good compared to our NDMP
> backups to LTO-2 tape which run at the nice clip of ~35MB/s.
>
>
>
> Thanks,
>
> Eddy
>
>
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