Do the client backup sessions pin the log? What is the throughput on the
actual client session and are these backups direct to disk? If the
sessions are cancelled does the system come back to life?

15 TB of SATA sounds like a lot of storage. how has this been
added/configured- What raw throughput do you get on these disks outside of
TSM itself?

You say the LTO3 drives are new. Do you have existing LTO3 drives? Have
you configured them correctly with new device class etc if you are mixing
LTO generations in the library?

I have seen this type of pinning/dramatic slow down before. I saw itself
manifest by the server hitting the maxsessions limit as all the sessions
were running so slowly to the disk pool.

Lots of questions i know, but as you have made multiple changes at the
same time- its going to be difficult to nail down without additional info.

Ian Smith
-------------------------------------------------------
Core Engineering - Storage





Robert Clark <Robert_Clark AT MAC DOT COM>
Sent by: "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>
27/07/2007 18:01
Please respond to
"ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>


To
ADSM-L AT VM.MARIST DOT EDU
cc

Subject
Re: [ADSM-L] TSM performance very poor, Recovery log is being pinned






Is the SATA setup as disk storage pools? Is it filesystem or raw
logical volumes?

What is the OS? vmstat or top/topas may give some ideas.

What is the network transport? Fast ethernet?

[RC]

On Jul 27, 2007, at 2:49 AM, Craig Ross wrote:

> 10 days ago I Recently added 15TB of SATA storage and a new Fabric
> with 4
> new LTO drives to our 3584 library,
> The DB is approx 90GB TSM
>
> Few days ago I noticed processing had ground to halt, after digging
> around I
> have found as soon as server gets busy maybe 4 processes 8 or so
> sessions
> the recovery log begins "sh logpinned" to pin and the Database gets
> locks.
> Shown by running "sh locks"
> And as result the server suffers!
> Now today I have stopped using the new Tech LTO 3 and SATA and
> things are
> coping better but still worse than previous as soon as load is
> increased Log
> pins and processing slows drastically.
>
> Are there any steps I can take which will help my scenario.
> Would a DB UNLOAD RELOAD help that much?
>
> Reference: Recovery log has heaps of room DB has heaps of room 90Gb
> DB with
> 100GB of room.
>
> Any advice is much appreciated.



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