[Tmem-devel] tmem centos kernel from downloads or from patch 2.6.18-194.11.1.el5xen

[Dan Magenheimer]

Hi Vasiliy --

I am guessing that there is a bug in the "min_target_pages()"
function (also known as minimum_target() in the xen tree)
when memory is very large.  I don't have easy access to a
machine with large physical memory... though a colleague
tested this same patch once on a machine with 256GB and it
worked fine.

Or... how much swapspace to you have configured for your
domU?  If there is NO swapspace configured at all or if it
is very very small, I think this might cause OOMs.

Thanks,
Dan

> -----Original Message-----
> From: Vasiliy G Tolstov [mailto:v.tolstov at selfip.ru]
> Sent: Wednesday, August 18, 2010 9:51 AM
> To: Dan Magenheimer
> Cc: tmem-devel at oss.oracle.com
> Subject: RE: [Tmem-devel] tmem centos kernel from downloads or from
> patch 2.6.18-194.11.1.el5xen
> 
> В Срд, 18/08/2010 в 08:46 -0700, Dan Magenheimer пишет:
> > > > The oom-killer may be invoked if the balloon driver does
> > > > not have the balloon driver code fragment that limits
> > > > the minimum memory.
> > >
> > > I'm build from source rpm downloaded from oss.oracle.com and try it
> by
> > > kernel /boot/vmlinuz-2.6.18-194.3.1.0.2.el5.tmemxen root=/dev/xvda1
> > > console=xvc0 tmem noselfshrink
> > >
> > > But in domU oom-killer kills all programs. I think the patch to
> > > redhat/centos is bad and does not correct limit minimal memory to
> > > shrink.
> >
> > I have not seen this behavior with this rpm.  Could you provide
> > more detail on the exact steps you used to get to this point?
> > Including things like Xen version number, how much physical
> > memory you have on the physical machine, vm.cfg file parameters
> > etc.?
> >
> > Thanks,
> > Dan
> 
> Download source rpm do rpmbuild --with xenonly -ba spec-file; rpm -ivh
> resulted kernel-xen x86_86 rpm.
> 
> domU config file:
> bootloader = "/usr/bin/pygrub"
> name = "vps-21-25"
> vif = [ 'mac=00:16:3e:00:01:da,ip=188.127.237.66' ]
> disk = ['tap:aio:/mnt/storage/sas/21-25,xvda1,w']
> memory = 5000
> maxmem = 60000
> vcpus = 2
> maxvcpus = 14
> cpu_cap = 200
> cpu_weight = 2048
> vfb=['type=vnc,vncpasswd=E2G4R2s2W1']
> localtime=1
> 
> xm info on dom0:
> host                   : xen42
> release                : 2.6.32.13-0.5-xen
> version                : #1 SMP 2010-07-20 14:12:19 +0200
> machine                : x86_64
> nr_cpus                : 16
> nr_nodes               : 2
> cores_per_socket       : 4
> threads_per_core       : 2
> cpu_mhz                : 2266
> hw_caps                :
> bfebfbff:28100800:00000000:00001b40:009ce3bd:00000000:00000001:00000000
> virt_caps              : hvm hvm_directio
> total_memory           : 65455
> free_memory            : 50595
> free_cpus              : 0
> max_free_memory        : 50595
> max_para_memory        : 50591
> max_hvm_memory         : 50464
> node_to_cpu            : node0:0-3,8-11
>                          node1:4-7,12-15
> node_to_memory         : node0:28581
>                          node1:22013
> node_to_dma32_mem      : node0:2987
>                          node1:0
> max_node_id            : 1
> xen_major              : 4
> xen_minor              : 0
> xen_extra              : .0_21091_04-0.2
> xen_caps               : xen-3.0-x86_64 xen-3.0-x86_32p hvm-3.0-x86_32
> hvm-3.0-x86_32p hvm-3.0-x86_64
> xen_scheduler          : credit
> xen_pagesize           : 4096
> platform_params        : virt_start=0xffff800000000000
> xen_changeset          : 21091
> xen_commandline        : tmem=1 loglvl=all noreboot dom0_mem=2048M
> dom0_max_vcpus=2 dom0_vcpus_pin console=vga vga=current
> cc_compiler            : gcc version 4.3.4 [gcc-4_3-branch revision
> 152973] (SUSE Linux)
> cc_compile_by          : abuild
> cc_compile_domain      :
> cc_compile_date        : Thu May 20 11:44:41 UTC 2010
> xend_config_format     : 4
> 
> 
> --
> Vasiliy G Tolstov <v.tolstov at selfip.ru>
> Selfip.Ru
>