On Mon, 2009-11-09 at 08:55 -0300, Reinaldo de Carvalho wrote: > On Mon, Nov 9, 2009 at 8:43 AM, Sebastian Hagedorn > <Hagedorn@xxxxxxxxxxxx> wrote: > > --On 9. November 2009 08:37:46 -0300 Reinaldo de Carvalho > > <reinaldoc@xxxxxxxxx> wrote: > >> You need analyse the I/O consumition. > >> # iostat -d 1 > > I trust real world experiences more than benchmarks ... either people on > > this list have successfully run Cyrus under ESX or they haven't. I don't > > want to be the first to try it. > A lower I/O consumition should always to work fine in virtualization. "Lower" than what? This statement is meaningless. We run a ~500-600 connection Cyrus in ESX. But that isn't ~2,500. There are so many variables here. How much I/O your hypervisor can absorb depends on the same thing as a metal system - the underlying I/O subsystem. So far with ESX I've seen that the I/O subsystem bottlenecks before there is any 'hard limit' in the hypervisor; just like a metal system bottlenecks before any 'hard limit' in a [modern/recent] OS. The real problem with virtualization is that it becomes almost trivial to over-subscribe the system, it works great so long as only a few systems load spike at once - when seven or eight servers load spike at the same time things get ugly and the poor sys-admin's cell phone gets inundated with SMS alerts. ---- Cyrus Home Page: http://cyrusimap.web.cmu.edu/ Cyrus Wiki/FAQ: http://cyrusimap.web.cmu.edu/twiki List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html
