Hi Matthew, We did some tests for this, and we found out the cap is per VM.
Below link says weight was changed to per VCPU. http://blog.xen.org/index.php/2010/08/13/rfc-credit1-make-weight-per-vcpu/ Thanks for bringing this up. Will fix this bug soon. Thanks, Anthony > -----Original Message----- > From: Anthony Xu [mailto:xuefei...@citrix.com] > Sent: Thursday, June 14, 2012 2:31 PM > To: cloudstack-dev@incubator.apache.org > Subject: RE: CPU CAP XenServer > > Hi Matthew, > > That's a very good question, thanks for bringing this up. > When we implemented cap/weight for XenServer, we thought cap/weight is > per VCPU not per VM. > If cap is wrong, then weight is also wrong. > > In all articles you referred to , they don't explicitly say if the > domain is a single VCPU domain or a SMP domain. > > By default, the weight is 256. If weight is per domain/VM, 4VCPU VM > should get the same CPU cycle as 1VCPU VM, because they have same > weight 256. > It doesn't make any sense to me, so we thought cap/weight is per VCPU. > > I'll get back to you soon with definite answer. > > Anthony > > > > > > -----Original Message----- > > From: Matthew Hartmann [mailto:mhartm...@tls.net] > > Sent: Thursday, June 14, 2012 7:33 AM > > To: cloudstack-dev@incubator.apache.org > > Subject: Re: CPU CAP XenServer > > > > Hello: > > > > I reported this issue as a bug way back when 2.2.13 was released and > it > > has yet to be resolved. It still exists as a bug even in 3.0.2. > > > > http://bugs.cloudstack.org/browse/CS-12972 > > > > Please feel free to submit your comments to the bug report. > > > > Cheers, > > > > Matthew > > > > > > On 6/14/2012 10:26 AM, Diego Spinola Castro wrote: > > > Hi, i found a issue and want know that it's a real issue. > > > I've created a service offering with CPU CAP enabled and after > > deployment > > > i figured out that cap might be wrong. > > > > > > > > > Host: Intel(R) Xeon(R) CPU E5-2630 0 @ 2.30GHz > > > > > > > > > Service Offering: 4 x 2.0 GHz > > > > > > > > > VM: VCPUs-params (MRW): weight: 220; cap: 86 > > > VCPUs-max ( RW): 4 > > > VCPUs-at-startup ( RW): 4 > > > > > > > > > > > > http://support.citrix.com/article/CTX117960 > > > "The cap is expressed in percentage of one physical CPU: 100 is one > > > physical CPU, 50 is half a CPU, 400 is 4 CPUs, and so on. The > default, > > 0 > > > (zero), means there is no upper cap." > > > > > > > > > I believe that cpu cap should be 344 instead 86. > > > > > > Any thoughts? > > >
