What is the correct size for guest OS virtual memory.

[vijayrana968]

I have 4 server VMs where given memory is 256 GB on each VM. The virtual memory is set 4 GB on each VM's guest OS.

I see there is 256GB swap file created in each VM's respective folder. I just want to know, since there is VSWP technique, how virtual memory will come into picture and how much correct size should be set inside guest OS when RAM is 256GB. I am getting frequent logs on server where I have to reboot server everytime to fix memory issue.

Windows successfully diagnosed a low virtual memory condition. The following programs consumed the most virtual memory: QVS.exe (2808) consumed 273415946240 bytes, svchost.exe (220) consumed 154615808 bytes, and mcshield.exe (2900) consumed 146944000 bytes.

[rcporto]

Usually the size of paging file you should configure inside the Guest OS is 1.5x the size of RAM, or let Windows automatically manage the size of paging size. Take in mind that your Guest OS are not aware of your. vswp file, that file is used by the hypervisor in case of physical memory contention of your host.

[vijayrana968]

That 1.5 page-file of ram formula has gone in newer OS as far as I know, or In that way I will have to set pagefile to 384GB for 256GB RAM which is not good idea.

The pint to catch up from your reply is vswp is something when it comes at host level, I will try to find out correct size of pagefile at guest OS level.

Thanks for help.

[rcporto]

Agree that 1.5x maybe not be a good idea, this is why today I prefer let the Windows manage the paging file size. Anyway, take a look at the following blog post: Page File – The definitive guide – Windows Performance & Troubleshooting