Anthony Liguori wrote: > Izik Eidus wrote: >> this patchs allow the guest not shadowed memory to be swapped out. >> >> to make it the must effective you should run -kvm-shadow-memory 1 >> (witch will make your machine slow) >> with -kvm-shadow-memory 1, 3giga memory guest can get to be just >> 32mb on physical host! >> >> when not using -kvm-shadow-memory, i saw 4100mb machine getting to as >> low as 168mb on the physical host (not as bad as i thought it would >> be, and surely not as bad as it can be with 41mb of shadow pages :)) >> > > So what exactly does this option do? Is it really worth exposing it > as an option if it slows down guests so much? > > At least, a better name for the option would be nice. > > Regards, > > Anthony Liguori -kvm-shadow-memory was included in kvm from version 46. it control how much pages will be allocated to the shadow cache, (from version 46 the default is 2% of the system (so 4.1giga have about 80 mbs of shadow cache by default)) the problem is that each page that present at the shadow cache ( mmu pages ) cant be swapped out, so as lower as the number of shadow caches you have as more swappable will be useful.
(this option (kvm-shadow-memory) was included to make it possible that as less as possible shadow cache memory will be deleated ( beacuse it have big overhead to lose this cache) ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
