I'd also keep an eye on local I/O... we've found this to be the resource which can cause the worst noisy neighbours. Swapping makes this worse.
Tim > -----Original Message----- > From: George Shuklin [mailto:george.shuk...@gmail.com] > Sent: 21 April 2015 23:55 > To: openstack-operators@lists.openstack.org > Subject: Re: [Openstack-operators] over commit ratios > > It's very depend on production type. > > If you can control guests and predict their memory consumption, use it as base > for ratio. > If you can't (typical for public clouds) - use 1 or smaller with > reserved_host_memory_mb in nova.conf. > > And one more: some swap sapce is really necessary. Add at least twice of > reserved_host_memory_mb - it really improves performance and prevents > strange OOMs in the situation of very large host with very small dom0 > footprint. > > On 04/21/2015 10:59 PM, Caius Howcroft wrote: > > Just a general question: what kind of over commit ratios do people > > normally run in production with? > > > > We currently run 2 for cpu and 1 for memory (with some held back for > > OS/ceph) > > > > i.e.: > > default['bcpc']['nova']['ram_allocation_ratio'] = 1.0 > > default['bcpc']['nova']['reserved_host_memory_mb'] = 1024 # often > > larger default['bcpc']['nova']['cpu_allocation_ratio'] = 2.0 > > > > Caius > > > > > _______________________________________________ > OpenStack-operators mailing list > OpenStack-operators@lists.openstack.org > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators _______________________________________________ OpenStack-operators mailing list OpenStack-operators@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators
