A friend of mine suggested that I could get more memory related performance out of my servers by using fast disk for swap. Specifically, I could buy 1TB of SSD disk and have a dom0 Xen server swapon it. E.g. the largest VM server in my organization's data center has 128G of RAM. If I needed to run more VMs and some percentage of them could take a slight performance hit, then I could allocate 256G of SSD as swap space to up to four equally large servers to have RAM*2 of swap. I could then rely on Linux's paging algorithm to prioritize for those VMs that really need real RAM and run a lot more VMs for cheaper than if I had to buy 1TB of RAM.
Disclaimer: I have not tried this.
1 comment:
Ask Slashdot: Software SSD Cache Implementation For Linux? has generated more detail on this subject.
Post a Comment