Hi Andy,
I've changed the thresholds to hi=50 lo=40 for the larger disk pools that
are over 600GB. I also empty them out once a day by changing the
thresholds to hi=0 lo=0. My current problem is that the SATA disk isn't
reading fast enough and writing to our tapes quick enough. I usually empty
out the stgpools to 0% every night for the client backups, and then copy
the disk to the offsite copy and then migrate the disk pools to the onsite
tape pool. Lately, since I have added the extra SATA disk, I cannot get
the disk cleared off to tape. I did add the volumes in 32 & 64GB volumes.
Should I recreate smaller disk pool volumes? Is there a maximum size limit
for them? I didn't find anything, but I'm thinking that I missed something
here. Any suggestions are greatly appreciated!!! Thanks!
********************************
Joni Moyer
Highmark
Storage Systems
Work:(717)302-6603
Fax:(717)302-5974
joni.moyer AT highmark DOT com
********************************
"Andrew Raibeck"
<storman AT US DOT IBM.C
OM> To
Sent by: "ADSM: ADSM-L AT VM.MARIST DOT EDU
Dist Stor cc
Manager"
<[email protected] Subject
.EDU> Re: Migration Speed Has Plummeted
08/17/2005 11:25
AM
Please respond to
"ADSM: Dist Stor
Manager"
<[email protected]
.EDU>
Hi Joni,
I notice your high migration threshold is 70 and low migration threshold
is 60. Such a narrow threshold width could cause problems, since migration
will taper off once the utilization drops below 60%. This means that more
than half the pool is left populated with otherwise migratable data. Maybe
those settings are transitory, and are changed later during your TSM daily
activity; or maybe they are deliberate... but I thought I'd ask.
Regards,
Andy
Andy Raibeck
IBM Software Group
Tivoli Storage Manager Client Development
Internal Notes e-mail: Andrew Raibeck/Tucson/IBM@IBMUS
Internet e-mail: storman AT us.ibm DOT com
The only dumb question is the one that goes unasked.
The command line is your friend.
"Good enough" is the enemy of excellence.
"ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU> wrote on 2005-08-17
05:58:59:
> Hi Richard,
>
> My device class for the storage pools is DISK and I have read that it is
> better to use a device type of FILE when using ATA disk. Is this true
and
> if so, how can I correct this? Our disk is EMC ATA Raid-3. We thought
to
> get cheap disk as a landing spot for our backups and then do a quick
sweep
> to tape, but I'm really hurting here and we also have a data center move
> coming up so this is crucial for that move.
>
> I have the caching of the migrated files turned off. I believe that
this
> is the only place that caching comes into play with TSM? I thank you
for
> your help and any suggestions!!!
>
> Storage Pool Name ORACLE
>
> Storage Pool Type PRIMARY
>
> Device Class Name DISK
>
> Estimated Capacity (MB) 1032192.0
>
> Pct Util 96.2
>
> Pct Migr 96.2
>
> Pct Logical 100.0
>
> High Mig Pct 70
>
> Low Mig Pct 60
>
> Migration Processes 3
>
> Next Storage Pool TAPE_ORACLE
>
> Maximum Size Threshold -
>
> Access READWRITE
>
> Description Oracle Disk Storage Pool
>
> Overflow Location -
>
> Cache Migrated Files? NO
>
> Collocate? -
>
> Reclamation Threshold -
>
> Maximum Scratch Volumes Allowed -
>
> Delay Period for Volume Reuse -
>
> Migration in Progress? YES
>
> Amount Migrated (MB) -
>
> Elapsed Migration Time (seconds) 143029
>
> Reclamation in Progress? -
>
> Volume Being Migrated/Reclaimed -
>
> Last Update Date/Time 2005-08-16
20:30:16.000000
>
> Last Update by (administrator) LIDZR8V
>
> Reclaim Storage Pool -
>
> Migration Delay 0
>
> Migration Continue YES
>
> Storage Pool Data Format Native
>
> Copy Storage Pool(s) -
>
> Continue Copy on Error? -
>
> CRC Data NO
>
>
>
>
> ********************************
> Joni Moyer
> Highmark
> Storage Systems
> Work:(717)302-6603
> Fax:(717)302-5974
> joni.moyer AT highmark DOT com
> ********************************
>
>
>
> "Richard Sims"
> <rbs AT bu DOT edu>
> To
> 08/17/2005 08:35 "Joni Moyer"
> AM <joni.moyer AT highmark DOT com>
> cc
>
> Subject
> Re: Migration Speed Has Plummeted
>
>
>
>
>
>
>
>
>
>
> Joni - Save yourself some grief and check ADSM QuickFacts for caching.
> (It's a storage pool option.)
> As to the migration performance: You need to do fact gathering as
> part of
> analysis. With older tapes and drives, you may be encountering
> increasing
> difficulty in writing blocks on the old tapes, which should be
> reflected in
> the AIX Error Log, if happening. Disk transfer speed may be related
> to how
> it is set up (RAID type, etc.). Disks which the OS vendor (IBM) doesn't
> recognize may receive too-small queue limits. Here is one of my AIX
> notes:
>
> Disk performance Disk controllers typically
> afford some
> nice degree of parallelism
> in order to
> improve performance/
> throughput. Vendors
> tend to be parochail - or at
> least play
> it safe... If you attach an
> IBM disk to
> AIX, it sets attributes to a
> nice number
> for Queue Depth; but if you
> attach a
> non-IBM disk to AIX, it goes
> max
> conservative, limiting Queue
> Depth to 1,
> causing performance to suffer.
> Ref: AIX doc "Setting SCSI-
> Adapter and
> Disk-Device Queue Limits"
> System performance can
> essentially
> freeze if, for example, disk
> formatting
> is occurring on the Shark,
> and system
> paging space is also on the
> Shark.
> In AIX5, some settings you
> can make:
> 1. Change maxperm, minperm
> (away from
> their default setting of
> 75, 25).
> Possibly, lower maxperm
> to 24,
> minperm to 12.
> 2. Turn on I/O Pacing -
> judiciously, as
> it can also hurt
> performance.
> A simple way of testing disk
> speed is
> to time how long it takes to
> write a
> file of a given size, as via
> command:
> time dd if=/dev/zero bs=64k
> count=1000
> > /Some/DiskFile
> where the count value may be
> increased
> as needed.
> See also: minperm, maxperm;
> Queue Depth,
> disk attribute
>
> Also, if you fall behind in migration, things just get worse as disk
> fragmentation occurs, and the arm gets frantic exercise seeking all
> over the
> place for its next file block as a lot of distributed space on the
> disk is
> occupied by lingering data. This is one of the reasons that caching
> is a
> performance hit.
>
> Richard Sims
>
>
> On Aug 17, 2005, at 8:19 AM, Joni Moyer wrote:
>
> >
> > How do you know if caching is turned on? How/where can you turn it
> > off? I
> > am having lousy migration speed perfomance as well. What can I look
> > at/change? I have an AIX 5.2 server at TSM 5.2.4.0 with LTO2 tape
> > drives
> > attached. Thanks!
> >
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