Andrey, What i know:
1. KVM not maps directly vRAM to physical.So VM will use just as much as it needs. 2. Red Hat recommends<https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/5/html/Virtualization/sect-Virtualization-Tips_and_tricks-Overcommitting_with_KVM.html>to make swap partition with specific size to be protected from out of memory cases. (0.5 * RAM) + (overcommit ratio * RAM) = Recommended swap size I think it is reasonable solution, because most of the loads are far from 100%. But i agree in case if 100% load applications it's reasonable to make it <=1. Thanks On Sat, Apr 5, 2014 at 12:42 AM, Andrey Korolev <[email protected]>wrote: > Just a small question - how the hell memory overcommit can be higher > than 1? This will result in OOM and continuous weird behavior as soon > as enough number of VMs will be launched. > > On Sat, Apr 5, 2014 at 3:02 AM, Roman Sokolkov <[email protected]> > wrote: > > Just small update about overcommit ratios > > > > As recommended by Red Hat > > vCPU/CPU (cpu_allocation_ratio) = 5 (default 16) > > vRAM/RAM (ram_allocation_ratio) = 1.5 > > > > Thanks. > > > > > > > > On Fri, Apr 4, 2014 at 1:04 PM, Roman Sokolkov <[email protected]> > > wrote: > >> > >> Folks, > >> > >> Any updates on that? > >> Customers that run Fuel for production exactly need finely tuned > >> scheduler. > >> My two latest projects were affected by default "RAW" scheduling. > >> > >> Thank you. > >> > >> > >> On Fri, Mar 21, 2014 at 7:18 AM, Bogdan Dobrelya < > [email protected]> > >> wrote: > >>> > >>> On 03/21/2014 03:04 PM, Dmitry Ukov wrote: > >>> > Core and Disk filters should be enabled (they are disabled by > default) > >>> > in order to avoid compute node oveloading > >>> > - cpu_allocation_ratio=1.0 - was customer requirement. I think 16.0 > is > >>> > way to big over commit ratio (potentially 16 vms on 1 core). I would > >>> > say > >>> > 2.0 or 3.0 will be reasonable here. > >>> > - disk_allocation_ratio=1.0 - it is unsafe to over commit disk > >>> > - ram_allocation_ratio=1.0 - this was customer requirement. Actually > we > >>> > can use default value here. (AFAIR default is 1.5 ) > >>> > - ram_weight_multiplier=0.0 and scheduler_host_subset_size=30 will > help > >>> > us to get random VMs distribution if compute nodes significantly > differ > >>> > from each other in terms of total RAM amount > >>> > >>> Thank you, that makes sense. I vote for enable these ones (leaving the > >>> ram_allocation_ratio defaults) for Fuel nova manifests for Puppet. That > >>> do you think? > >>> > >>> > > >>> > > >>> > > >>> > On Thu, Mar 20, 2014 at 2:58 PM, Bogdan Dobrelya > >>> > <[email protected] > >>> > <mailto:[email protected]>> wrote: > >>> > > >>> > On 03/20/2014 08:47 AM, Mike Scherbakov wrote: > >>> > > Hi Dmitry, > >>> > > I was running through bp created by > >>> > > you: > >>> > > >>> > > https://blueprints.launchpad.net/fuel/+spec/scheduler-config-improvements. > >>> > > > >>> > > >>> > Interesting, why CPU overcommitment defaults ( > >>> > > >>> > > https://github.com/openstack/nova/blob/master/etc/nova/nova.conf.sample#L1759 > >>> > ) are so 'bad' to being changed so drastically 16->1? > >>> > > >>> > > I'm wondering whether this config will work fine for every > >>> > installation > >>> > > we do with Fuel.. what are the possible limitations / corner > >>> > cases? > >>> > > > >>> > > Thanks, > >>> > > -- > >>> > > Mike Scherbakov > >>> > > #mihgen > >>> > > > >>> > > > >>> > > >>> > > >>> > -- > >>> > Best regards, > >>> > Bogdan Dobrelya, > >>> > Skype #bogdando_at_yahoo.com <http://bogdando_at_yahoo.com> > >>> > Irc #bogdando > >>> > > >>> > > >>> > > >>> > > >>> > -- > >>> > Kind regards > >>> > Dmitry Ukov > >>> > IT Engineer > >>> > Mirantis, Inc. > >>> > > >>> > >>> > >>> -- > >>> Best regards, > >>> Bogdan Dobrelya, > >>> Skype #bogdando_at_yahoo.com > >>> Irc #bogdando > >>> > >>> -- > >>> Mailing list: https://launchpad.net/~fuel-dev > >>> Post to : [email protected] > >>> Unsubscribe : https://launchpad.net/~fuel-dev > >>> More help : https://help.launchpad.net/ListHelp > >> > >> > >> > >> > >> -- > >> Roman Sokolkov, > >> Deployment Engineer, > >> Mirantis, Inc. > >> Skype rsokolkov, > >> [email protected] > > > > > > > > > > -- > > Roman Sokolkov, > > Deployment Engineer, > > Mirantis, Inc. > > Skype rsokolkov, > > [email protected] > > > > -- > > Mailing list: https://launchpad.net/~fuel-dev > > Post to : [email protected] > > Unsubscribe : https://launchpad.net/~fuel-dev > > More help : https://help.launchpad.net/ListHelp > > > -- Roman Sokolkov, Deployment Engineer, Mirantis, Inc. Skype rsokolkov, [email protected]
-- Mailing list: https://launchpad.net/~fuel-dev Post to : [email protected] Unsubscribe : https://launchpad.net/~fuel-dev More help : https://help.launchpad.net/ListHelp
