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Extreme Memory Oversubscription For VMs
Laxitive writes "Virtualization systems currently have a pretty easy time oversubscribing CPUs (running lots of VMs on a few CPUs), but have had a very hard time oversubscribing memory. GridCentric, a virtualization startup, just posted on their blog a video demoing the creation of 16 one-gigabyte desktop VMs (running X) on a computer with just 5 gigs of RAM. The blog post includes a good explanation of how this is accomplished, along with a description of how it's different from the major approaches being used today (memory ballooning, VMWare's page sharing, etc.). Their method is based on a combination of lightweight VM cloning (sort of like fork() for VMs) and on-demand paging. Seems like the 'other half' of resource oversubscription for VMs might finally be here."
Please name me a server which requires multiple 24x7x365 operation and which should be suspended to disk. They are mutually exclusive concepts. Either the server needs to be up and running or it doesn't. If it doesn't, and therefore can be suspended, it can be upgraded and rebooted.
It was inescapably implied. Go re-read it. By definition, any system which requires non-stop operation and uptime measured in years is exactly as I described. After all, the entire premise is that these are requirements and even moreso, paging is to be used to avoid application restarts and/or system reboot so as to work around a horrible memory leak.
Swap space is useful on Linux LAPTOPS, TABLETS and sometimes even DESKTOPS/WORKSTATIONS for suspend to disk.
No one said otherwise.