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Are there any documents going more deeply in these sort of considerations?=

This is exactly what I have been searching for lately, too. Please let me k= now if you find anything (or blog posts, forums, books, etc). Thank you! Sent from my mobile phone

On 6 Sep 2017, at 12:47, Gianluca Cecchi <gianluca.cecchi@gmail.com> wrote= : =20 Hello, I was talking with a guy expert in VMware and discussing performance of VM= s in respect of virtual cpus assigned to them in relation with mapping with t= he real hw of the hypervisor underneath. =20 One of the topics was numa usage and its overheads in case of a "too" big V= M, in terms of both number of vcpus and memory amount. Eg:=20 suppose host has 2 intel based sockets, with 6 cores and HT enabled and ha= s 96Gb of ram (distributed 48+48 between the 2 processors) suppose I configure a VM with 16 vcpus (2:4:2): would be the mapping respe= cted at physical level or only a sort of "hint" for the hypervisor? Can I say that it would perform better if I configure it 12 vcpus and mapp= ing 1:6:2, because it can stay all inside one cpu? =20 And what if I define a VM with 52Gb of ram? Can I say that it would perfor= m in general better if I try to get it all in one cpu related memory slots (= eg not more than 48Gb in my example)? =20 Are there any documents going more deeply in these sort of considerations?=

=20 Also, if one goes and sizes so that the biggest VM is able to all-stay ins= ide one cpu-memory, does it make sense to say that it will perform better in= this scenario a cluster composed by 4 nodes, each one with 1 socket and 48G= b of memory instead of a cluster of 2 nodes, each one with 2 sockets and 96G= b of ram? =20 Hope I have clarified my questions/doubts. =20 =20 Thanks in advance for any insight, Gianluca =20 _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

<div><br>On 6 Sep 2017, at 12:47, Gianluca Cecchi <<a href=3D"mailto:gia= nluca.cecchi@gmail.com">gianluca.cecchi@gmail.com</a>> wrote:<br><br></di= v><blockquote type=3D"cite"><div><div dir=3D"ltr">Hello,<div>I was talking w= ith a guy expert in VMware and discussing performance of VMs in respect of v= irtual cpus assigned to them in relation with mapping with the real hw of th= e hypervisor underneath.</div><div><br></div><div>One of the topics was numa= usage and its overheads in case of a "too" big VM, in terms of both number o= f vcpus and memory amount.</div><div>Eg: </div><div>suppose host has 2 i= ntel based sockets, with 6 cores and HT enabled and has 96Gb of ram (distrib= uted 48+48 between the 2 processors)</div><div>suppose I configure a VM with= 16 vcpus (2:4:2): would be the mapping respected at physical level or only a= sort of "hint" for the hypervisor?</div><div>Can I say that it would perfor= m better if I configure it 12 vcpus and mapping 1:6:2, because it can stay a= ll inside one cpu?</div><div><br></div><div>And what if I define a VM with 5= 2Gb of ram? Can I say that it would perform in general better if I try to ge= t it all in one cpu related memory slots (eg not more than 48Gb in my exampl= e)?</div><div><br></div><div>Are there any documents going more deeply in th= ese sort of considerations?</div><div><br></div><div>Also, if one goes and s= izes so that the biggest VM is able to all-stay inside one cpu-memory, does i= t make sense to say that it will perform better in this scenario a cluster c= omposed by 4 nodes, each one with 1 socket and 48Gb of memory instead of a c= luster of 2 nodes, each one with 2 sockets and 96Gb of ram?</div><div><br></=

<br></div><div>Thanks in advance for any insight,</div><div>Gianluca  = </div></div> </div></blockquote><blockquote type=3D"cite"><div><span>____________________= ___________________________</span><br><span>Users mailing list</span><br><sp= an><a href=3D"mailto:Users@ovirt.org">Users@ovirt.org</a></span><br><span><a=

--Apple-Mail-FC5CF2F4-77D9-4AB3-AECA-43D5365F3844 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable <html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=3D= utf-8"></head><body dir=3D"auto"><div><span></span></div><div><meta http-equ= iv=3D"content-type" content=3D"text/html; charset=3Dutf-8"><div><blockquote t= ype=3D"cite"><div dir=3D"ltr"><font color=3D"#000000"><span style=3D"backgro= und-color: rgba(255, 255, 255, 0);">Are there any documents going more deepl= y in these sort of considerations?</span></font></div></blockquote><div id=3D= "AppleMailSignature"><br></div>This is exactly what I have been searching fo= r lately, too.  Please let me know if you find anything (or blog posts,= forums, books, etc).  Thank you!<br><br>Sent from my mobile phone</div= div><div>Hope I have clarified my questions/doubts.</div><div><br></div><div= href=3D"http://lists.ovirt.org/mailman/listinfo/users">http://lists.ovirt.o= rg/mailman/listinfo/users</a></span><br></div></blockquote></div></body></ht= ml>= --Apple-Mail-FC5CF2F4-77D9-4AB3-AECA-43D5365F3844--