Hi, please notice the Shared Memory lines: node2: Shared Memory:57% vs. node3: Shared Memory:98% It seems you have overcommit enabled and KSM started deduplicating pages. This frees memory when there are multiple VMs that use identical pages. And node3 either has VMs that are similar or was just faster when searching for identical pages. Best regards -- Martin Sivak On Tue, Nov 13, 2018 at 8:13 AM, <patrickstar12358(a)hotmail.com&gt; wrote: > Hi buddy,I encoutered a issue: > Enviroment:ovirt 3.5,node2+node3+engine,node2 and node3 are in the same cluster. > node2:64GB memory > node3:64GB memory > If I try to start 25 VMs on node2,node2's Memory usage is almost up to 80% > But if I start 25 VMs on node3,node3's Memory usage is normal,about 70% > VMs are all the same. > And I checked out "Hosts>General". > on node2: > Physical Memory:64301 MB total, 49512 MB used, 14789 MB free > Swap Size:28567 MB total, -858090 MB used, 886657 MB free > Shared Memory:57% > Max free Memory for scheduling new VMs:24191 MB > Memory Page Sharing:Active > on node3: > Physical Memory:64301 MB total, 37938 MB used, 26363 MB free > Swap Size:28567 MB total, 161 MB used, 28406 MB free > Shared Memory:98% > Max free Memory for scheduling new VMs:24191 MB > Memory Page Sharing:Active > > Best regard > _______________________________________________ > Users mailing list -- users(a)ovirt.org > To unsubscribe send an email to users-leave(a)ovirt.org > Privacy Statement: https://www.ovirt.org/site/privacy-policy/ > oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ > List Archives: https://lists.ovirt.org/archives/list/users@ovirt.org/message/WXT7XIB2IKA...