After I observed large amount of virtual memory allocated by ovirt-engine, I found about MALLOC_MAX_ARENA and got to this wildfly ticket[1] which decided to start wildfly with default of 1. Unfortunately we don't use standlone.sh, so we miss those valuable additions. This change won't affect performance, but on machines with large amount of cores it will definitely mean less virtual memory allocation. I suggest going with what wildfly does by default and add this to our services/ovirt-engine.conf MALLOC_ARENA_MAX=1 Another approach would be to somehow use standalone.sh so we gain all the changes for free - but that of course is not free, it means a change to our home brew ovirt-engine.py. [1]https://issues.jboss.org/browse/WFCORE-2959 Version-Release number of selected component (if applicable): all How reproducible: 100% Steps to Reproduce: run ovirt-engine with MALLOC_ARENA_MAX set to 128 (to emulate a machine with 16 cores) and then 1, check RSS and Virtual memory using ps -o vsize,rss -p $(pidof ovirt-engine)
Moreover, high amount of virtual memory, will affect the oom_score of the ovirt-engine process, leading to it be even more likely be killed by oom. I can recall some reports to the mailing list about oom, maybe that can explain some of them.
The same optimization can be also used for ovirt-engine-notifier
(In reply to Martin Perina from comment #2) > The same optimization can be also used for ovirt-engine-notifier Might be. If the number of thread the notifier uses is small, which I assume it is, then it won't have an effect, but you are familiar with it more than I.
Verified that value of ENGINE_MALLOC_ARENA_MAX in /usr/share/ovirt-engine/services/ovirt-engine/ovirt-engine.conf is by default set to 1.
This bugzilla is included in oVirt 4.2.0 release, published on Dec 20th 2017. Since the problem described in this bug report should be resolved in oVirt 4.2.0 release, published on Dec 20th 2017, it has been closed with a resolution of CURRENT RELEASE. If the solution does not work for you, please open a new bug report.