![]() ![]() And performance tuning of uncapped LPARs (entitlement and virtual processors) is considerably harder - a lot depends on your workloads (how high are the peaks vs. You could make your processors uncapped, which will make it possible to use more than your entitlement, but the first consequence is that your licences are no longer based on entitlement but on the maximum number of processors that you can conceivably use. Which leads to cache invalidation and related problems, and may actually hurt performance. If you keep the entitlement at 4.0 but increase the VP to eight, you still get the same amount of CPU cycles per 10ms timeslice, but these cycles may now be spread over eight physical instead of four physical processors. an entitlement of 2.5 requires 3 virtual processors). In that case it doesn't make sense to make the number of virtual processors larger than the entitlement, other than rounding the entitlement up to the nearest whole number (e.g. You may also get some great info from the Java Performance Advisor: !/wiki/Power%20Systems/page/PowerVM%20Virtualization%20Performance%20Advisor You would either use 16 (to maximize the use of all hardware threads), or 8 or 4 (to benefit the most from virtual processor folding - which increases the per-thread throughput).įor further investigation, the PowerVM Virtualization Performance Advisor is probably a good start: I'm no WAS expert, but is this the number of WAS threads? Is that in any way configurable? Nine seems to be an odd number on a 4 core, 4-way SMT Power7 system. I'm also curious about the "9 running threads". ![]() As soon as you increase the entitlement, you may find your licence cost increasing as well. With your current config you can go as high as 8.0 entitlement / 8 virtual CPUs via a DLPAR operation (so without a reboot).Īt the moment you are running a 4.0 entitlement, capped, and that means that your WAS licence will be based on 4 CPUs. You might want to increase the entitlement (and you will need to increase the number of virtual processors at the same time) and see what happens. At a first glance I would indeed say that you don't have enough CPU resources. ![]()
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