Performance Test Problems with 64 bit Hash files on 8.7
Posted: Fri Nov 09, 2012 5:07 am
Am currently running some performance testing in preperation for a migration from 8.1 aix to 8.7 linux.
I am running a very simple test Server job to populate a 64 bit hash file with several million rows. The same job with the same data and hash files created with same settings perform very differently on the two DS versions. Whereas the 8.1 aix job completes in 15 mins the 8.7 version runs into hours.
Although the jobs sit in different test environments, both have very little running on them (and the jobs have been ran at various times with the same results) and I am led to believe should be similar in set up.
Jobs which read/write from flat file to flat file, to dev/null and to a 32 bit hash file (volumes just under two gig) on both 8.1 and 8.7 all perform at similar speeds.
The 64 bit hash file was created with the mkdbfile command.
The DS tunable settings appear to match.
As anyone experienced any such performance issues with 64 bit hash files on 8.7 or can anyone offer advice as to what to check that might specifically impact on jobs using 64 bit hash files?
Cheers.
I am running a very simple test Server job to populate a 64 bit hash file with several million rows. The same job with the same data and hash files created with same settings perform very differently on the two DS versions. Whereas the 8.1 aix job completes in 15 mins the 8.7 version runs into hours.
Although the jobs sit in different test environments, both have very little running on them (and the jobs have been ran at various times with the same results) and I am led to believe should be similar in set up.
Jobs which read/write from flat file to flat file, to dev/null and to a 32 bit hash file (volumes just under two gig) on both 8.1 and 8.7 all perform at similar speeds.
The 64 bit hash file was created with the mkdbfile command.
The DS tunable settings appear to match.
As anyone experienced any such performance issues with 64 bit hash files on 8.7 or can anyone offer advice as to what to check that might specifically impact on jobs using 64 bit hash files?
Cheers.