From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Williams Subject: Re: Possible regression: XEN 4.0.0 total_memory decrease Date: Thu, 15 Apr 2010 14:26:42 -0400 Message-ID: <4BC75A62.7000104@iweb.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: "Xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org Yes you're correct! Both hosts have dom0_mem=3D512M set. Xen 3.4.2: free_memory : 3514 Xen 4.0.0: free_memory : 3523 So now it appears to be a free memory INCREASE caused by this 'bug' ? ;) Thank you!!! Keir Fraser wrote: > Ah, hm, I think this is a bug in total memory reporting only. I think t= he > memory is still there in the free pools though. :-) How does xm info's > free_memory compare in the two cases? I bet it's a lot closer than 150M= B > (assuming dom0 is allocated the same amount of memory in both cases, e.= g., > by explicitly specifying dom0_mem=3Dxxx on Xen command line). >=20 > -- Keir >=20 > On 15/04/2010 18:33, "Alex Williams" wrote: >=20 >> Hello, >> >> Both builds run a 64-bit Xen kernel and 64-bit Dom0 kernel. >> >> (XEN) Xen kernel: 64-bit, lsb, compat32 >> (XEN) Dom0 kernel: 64-bit, lsb, paddr 0xffffffff80200000 -> >> 0xffffffff805d388c >> >> As for the RAM: >> >> Xen 3.4.2: (XEN) System RAM: 3946MB (4041012kB) >> Xen 4.0.0: (XEN) System RAM: 4084MB (4182064kB) >> >> I have also verified with only 2048MB installed in the system. Here ar= e >> the results: >> >> Xen 3.4.2: (XEN) System RAM: 2036MB (2084912kB) >> Xen 4.0.0: (XEN) System RAM: 1898MB (1943860kB) >> >> Still 150MB RAM missing... it appears this problem is static and >> independant of the amount of RAM installed in the system. >> >> Regards, >> >> >> >> Keir Fraser wrote: >>> Are the hypervisor and dom0 kernel 64-bit or 32-bit? Xen prints a mes= sage >>> "System RAM: xxx" early during boot. Do these differ significantly fo= r you >>> between 3.4.2 and 4.0.0? >>> >>> K. >>> >>> On 15/04/2010 16:54, "Alex Williams" wrote: >>> >>>> Hello, >>>> >>>> I noticed a significant *decrease* (150MB) in "total_memory" on a ho= st >>>> build using XEN 4.0.0 with kernel 2.6.18. >>>> >>>> Here are the details: >>>> >>>> Server =3D 4096MB RAM >>>> XEN 3.4.2 + kernel 2.6.18: xm info | grep total_memory =3D 4084 >>>> XEN 4.0.0 + kernel 2.6.18: xm info | grep total_memory =3D 3946 >>>> >>>> The exact same kernel config file was used for both builds. I also m= ade >>>> sure there is absolutely no difference on the hosts (while the build= s >>>> are created on a different machine). >>>> >>>> This seems like a regression, unless someone can provide suggestions= on >>>> how to correct this? >>>> >>>> Thanks. >>>> --=20 Alexander Williams IT Architecture Specialist Sp=E9cialiste de l'Architecture TI http://www.iWeb.com/