Gill, Geoffrey L. wrote:

I have a disk pool that is set Migration Continue=no, High Migration=80, Low
Migration=60. This disk pool is 390GB in size and every morning when I come
in migration is running, and would run till it is empty, I've seen it. I've
verified the settings during the migration and I see no reason that this
should be happening. The disk fills with SAP R/3 data each evening and some
other regular stuff.

Has anyone else come across this? I haven't seen the other disk pools I have
do this.

Geoff Gill
TSM Administrator
NT Systems Support Engineer
SAIC
E-Mail:    <mailto:gillg AT saic DOT com> gillg AT saic DOT com
Phone:  (858) 826-4062
Pager:   (877) 905-7154

Geoff,

Based on the information your are giving me I might offer this
explanation.  First of all "MIGContinue" only has meaning if you have
"MIGDelay" set to something other than 0, but I don't think that is a
factor here.  The way migration works is as follows:

  1. Once stg_pool utilization exceeds the "HIghmig" value a migration
     process or processes are started.
  2. ITSM will pick the largest single filespace backup (or archive
     package) in the stg_pool and move it AND all of the other
     filespaces for that node.
  3. Once all data for that node has been moved for that node ITSM
     checks to see if stg_pool utilization is below the  "LOwmig" value
     if not then go back to step 2.

There is a bit of a difference in this process if you use "MIGDelay" and
"MIGContinue", I have posted on that process several times before so I
want go through it all again.

I am guessing that since this stg_pool is for your SAP data which is
probably quite large that what you are seeing is a single node with data
that is a very large portion of the stg_pool space.  And therefore, once
ITSM starts to migrate it's data it will continue way past the low
threshold.  As you can see above, ITSM does not check "LOwmig" until
after it moves all data for a given node.  I beleive this is waht you
are seeing.

--
Regards,
Mark D. Rodriguez
President MDR Consulting, Inc.

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