Recently I started seeing this error while provisioning Xen VPSes on a server with 8GB of RAM: 12[2009-03-23 15:51:40 xend.XendDomainInfo 3310] DEBUG (XendDomainInfo:1603) XendDomainInfo.destroy: domid=None [2009-03-23 15:51:40 xend 3310] ERROR (xmlrpclib2:184) (12, ‘Cannot allocate memory’) I checked the memory, and sure enough, all of the VPSes were using up the memory. More specifically, dom0 (the main server) had ‘ballooned’ and begun to take up 3GB of RAM, this is more than the system should need: 12[2009-03-22 18:03:08 xend.XendDomainInfo 3310] DEBUG (XendDomainInfo:1113) Setting memory target of domain Domain-0 (0) to 2903 MiB. [2009-03-22 18:03:09 xend 3310] DEBUG (balloon:127) Balloon: 537840 KiB free; need 537600; done. Basically when memory ballooning is set, the memory available to the main hypervisor will have a minimum value set and will balloon according to the current requirements. This setting is in the config file which for me is at /etc/xen/xend-config.sxp: 1234# Dom0 will balloon out when….
Categories: CentOS,Configurations,System Administration,Xen
