Re: Possibly introduced bottleneck with DBPAGESHADOW

What is the performance with "mirrorwrite db sequential" compared to what
you have now? What storage do you use for dbvols?
You can point dbpageshadowfile to be somewhere else (where dbvols are)
using full path. You can also disable dbpageshadow but this introduces
some risk. On failure with incomplete BOTH writes the DB consistency
enforcement may require DB restore.

Zlatko Krastev
IT Consultant




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Subject:        Possibly introduced bottleneck with DBPAGESHADOW

It seems I may have introduced a bottleneck on my server by switching to
"mirrorwrite db parrallel" and addig dbpageshadow.  The default
dbpageshadow file goes in with /usr/tivoli/tsm/server/bin, which is on
my root vg (AIX server, 4.3.3 ML08).  It is mirrored SCSI disks.  I
noticed last night that hdisk0 and hdisk1 are getting hammered, with
little or no paging.  The manual seems unclear whether I can specify a
path before the filename or not.  Also, I am unsure whether the file is
needed in a disaster recovery scenario, when I have to restore my
database.  My gut says no, but I am not sure.  Any ideas?  What are
other people doing?  Thanks.

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