Is there an issue with vzsplit - if i use any value less than 15 i get the same value for PRiVVMPAGES and VMGUARPAGES (and others but these are ones that concern) [root@vps ~]# vzsplit -n 1 | grep -E "VMGUAR|PRIVVM" VMGUARPAGES="504818:2147483647" PRIVVMPAGES="504818:555299" [root@vps ~]# vzsplit -n 10 | grep -E "VMGUAR|PRIVVM" VMGUARPAGES="504818:2147483647" PRIVVMPAGES="504818:555299" [root@vps ~]# vzsplit -n 12 | grep -E "VMGUAR|PRIVVM" VMGUARPAGES="504818:2147483647" PRIVVMPAGES="504818:555299" [root@vps ~]# vzsplit -n 14 | grep -E "VMGUAR|PRIVVM" VMGUARPAGES="504818:2147483647" PRIVVMPAGES="504818:555299" [root@vps ~]# vzsplit -n 15 | grep -E "VMGUAR|PRIVVM" VMGUARPAGES="83261:2147483647" PRIVVMPAGES="499566:549522" The head of vzsplit shows the following: # Configuration file generated by vzsplit for 10 VEs # on HN with total amount of physical mem 3286 Mb # low memory 854 Mb, swap size 1983 Mb, Max treads 8000 # Resourse commit level 0: # Free resource distribution. Any parameters may be increased # Primary parameters As i was only doing a split of 10 this was totally over allocating resources. This is happening using Fedora5 and Fedora6 as the main HN. Also two seperate kernels Linux xxxx 2.6.18-ovz028stab027.1-smp #1 SMP Mon Apr 9 16:21:10 MSD 2007 i686 i686 i386 GNU/Linux and Linux xxxx.com 2.6.18-8.1.15.el5.028stab049.1 #1 SMP Thu Nov 8 16:23:12 MSK 2007 i686 i686 i386 GNU/Linux Any ideas on the cause of this and how to fix? This has caused an issue as without realising it was seriously over commiting resources, deliberatly used the vzsplit command to avoid this happening!
We do not recommend to allow one VE to allocate more than 60% RAM http://wiki.openvz.org/UBC_systemwide_config uration#Limiting_memory_allocations On the other hand it looks like vmguar barrier is set incorrectly for n<15. I've fixed recently this issue recently and would recoomed you upgrade vzctl package up to vzctl-3.0.22 version where thi issue is fixed. thank you, Vasily Averin
using more than 60% of resources was definitly not what was intended hence the use of vzsplit. I have just updated to the latest vzsplit and this does indeed seem to have sorted this issue - now to go and update lots of config files to proper limits