Saturday, July 28, 2012

DB2 Connect high CPU utilization

DB2 Connect servers are usually a good target for consolidation. Recently we observed relatively high CPU utilization even though only a small workload was being used. The oprofile and strace output showed that the system was busy doing semget() calls that failed. So a resource was missing. In the end it turned out to be a known problem in DB2 which is fixed starting DB2 9.7 FP5 and can also be circumvented in older versions by issuing a "db2trc alloc" during startup.
This is a typical consolidation problem - on individual dedicated servers this usually is not even noticed - however after consolidation this will be visible. An additional positive effect of fixing the problem is an improved throughput at higher transaction rates.

0 comments:

Post a Comment

:) :)) ;(( :-) =)) ;( ;-( :d :-d @-) :p :o :>) (o) [-( :-? (p) :-s (m) 8-) :-t :-b b-( :-# =p~ $-) (b) (f) x-) (k) (h) (c) cheer
Click to see the code!
To insert emoticon you must added at least one space before the code.