All my primary stgpools are on SAN disk.  SAN is nicely configured and well 
behaved.  During our days of distress, the I/O Wait % surpassed 95%. Now it 
varies from 30-50%.

For comparison, I went thru the stats for 2 machines, similar in size, running 
at about the same time during the backup window.  The session rate for the TDP 
client varied from 8-11 M/s.  The regular ba client ran at 1-3 K/s with SSDPCM, 
but 600-900 K/s with SSD.  I see similar figures on all machines where the 
backups were slow.  On the machines with migration problems, the transfer rate 
was under 1 M/s with SSDPCM but 25-30 M/s with SSD.



-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of 
Marcel Anthonijsz
Sent: Thursday, December 10, 2009 6:58 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: [ADSM-L] I/O thruput

Was the TSM server updated with the SDDPCM drivers as well?

Or are the incremental File system backups going to disk (thus using
the SDDPCM driver on TSM server) and the TDP going directly to tape
(either via lan-free or on the TSM server). Check your used mgt class
for the TDP backup.

And nmon running is IMHO _always_ a good idea, to keep track of your
performance.

2009/12/10 Remco Post <r.post AT plcs DOT nl>:
> are the tdp sessions either lan-free or going directly to tape?
>
> as with any performance issue: measure every parameter in the system. Have 
> nmon running during the night, logging all metrics... I'm not convinced that 
> the sdd driver change is the only contributing factor,,,,
>
> On 10 dec 2009, at 23:16, Fred Johanson wrote:
>
>>
>> My 6 boxes are TSM 5.5.3.0 on AIX  5.3.11.  The change was to upgrade a 
>> driver from SDD to SDDPCM 2.2.03, whatever that means.  On each machine I/O 
>> went to hell.  On 3 backups went normally, but migration crawled.  On the 
>> other 3 migrations went fine but backups were almost non-existent.  The 
>> exception on all 6 was that TDP and SQLBacktrack went normally.  We backed 
>> out the changes and things are back to normal.
>>
>> The unanswered question that management wants to know is why the TDP weren't 
>> affected.


-- 
Kind Regards, Groetje,

Marcel Anthonijsz
T: +31(0)299-776768
M:+31(0)6-2423 6522