From: Dominique L. <Dominique.Leuenberger@TMF-Group.com> - 2008-05-27 07:29:01
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>>> On 26.05.2008 at 21:50, Elliot Lee <el...@vm...> wrote: > Hi Dominique, > > Vmmemctl implements memory ballooning. Basically this means that when the > host wants to get some memory back from the guest, the host calls the > balloon driver in the guest, which just allocates a chunk of guest memory > and informs the host where that memory is. The virtual machine monitor can > then allocate that RAM to other guests, or to the host OS. When the host is > done with that memory, it will return it to the guest's pool of RAM, and > tell the guest's balloon driver to free up that memory so it can be used by > the guest OS again. > > The only way for the balloon driver to make a difference is if the host is > under memory pressure (perhaps because the apps in the host want memory, or > perhaps because another guest wants the memory). Memory ballooning is a > great way to not only allow reclaiming memory from a guest, but also to put > the guest OS under memory pressure so it will get rid of stuff that is not > really needed (e.g. swapping out unused applications in the guest). Elliot, Thank you very much for this explanation. This makes things a lot cleared ;) Dominique |