[CentOS-virt] Cannot allocate Memory

Pasi Kärkkäinen
Sun, 26 Jun 2016 16:30:57 -0000

On Wed, Jun 22, 2016 at 05:45:05PM +0000, Shaun Reitan
wrote:
>    Any of you guys ever seen an issue with Xen 4.4 were xm cannot create a
>    guest because of what looks like an issue allocating memory even though
xm
>    info shows like 5x the amount of free memory needed? We are still
>    unfortunately still using xm... it's on my list, i know..
>    We've had this happen on a couple hosts now.  Only way to resolve
seams to
>    be rebooting the host.  I'm going to update the host to latest Xen
4.4 now
>    hoping this is a old bug.
>    Here's from xen logs
>    [2016-06-22 09:13:50 1958] DEBUG (XendDomainInfo:105)
>    XendDomainInfo.create(['vm', ['name', 'xxx'],
['memory', 2048],
>    ['on_xend_start', 'ignore'], ['on_xend_stop',
'ignore'], ['vcpus', 2],
>    ['oos', 1], ['image', ['linux',
['kernel', '/kernels/vmlinux-2.6.18.8-4'],
>    ['videoram', 4], ['args', 'root=/dev/xvda ro
xencons=tty console=tty1 '],
>    ['tsc_mode', 0], ['nomigrate', 0]]],
['s3_integrity', 1], ['device',
>    ['vbd', ['uname', 'phy:vg/fs_6818'],
['dev', 'xvda'], ['mode', 'w']]],
>    ['device', ['vbd', ['uname',
'phy:vg/fs_6819'], ['dev', 'xvdb'], ['mode',
>    'w']]], ['device', ['vif', ['rate',
'40mb/s'], ['mac',
>    'FE:FD:48:01:F1:E7']]]])
>    [2016-06-22 09:13:50 1958] DEBUG (XendDomainInfo:2504)
>    XendDomainInfo.constructDomain
>    [2016-06-22 09:13:50 1958] DEBUG (balloon:187) Balloon: 7602632 KiB
free;
>    need 16384; done.
>

Hmm.. so you're using (dom0) memory ballooning? You might want to disable
it.
Things worked better without ballooning (at least with xend).


-- Pasi

>    [2016-06-22 09:13:50 1958] ERROR (XendDomainInfo:2566) (12, 'Cannot
>    allocate memory')
>    Traceback (most recent call last):
>      File
"/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py",
>    line 2561, in _constructDomain
>        target = self.info.target())
>    Error: (12, 'Cannot allocate memory')
>    [2016-06-22 09:13:50 1958] ERROR (XendDomainInfo:490) VM start failed
>    Traceback (most recent call last):
>      File
"/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py",
>    line 475, in start
>        XendTask.log_progress(0, 30, self._constructDomain)
>      File
"/usr/lib64/python2.6/site-packages/xen/xend/XendTask.py", line
>    209, in log_progress
>        retval = func(*args, **kwds)
>      File
"/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py",
>    line 2572, in _constructDomain
>        raise VmError(failmsg)
>    VmError: Creating domain failed: name=xxx
>    [2016-06-22 09:13:50 1958] ERROR (XendDomainInfo:110) Domain
construction
>    failed
>    Traceback (most recent call last):
>      File
"/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py",
>    line 108, in create
>        vm.start()
>      File
"/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py",
>    line 475, in start
>        XendTask.log_progress(0, 30, self._constructDomain)
>      File
"/usr/lib64/python2.6/site-packages/xen/xend/XendTask.py", line
>    209, in log_progress
>        retval = func(*args, **kwds)
>      File
"/usr/lib64/python2.6/site-packages/xen/xend/XendDomainInfo.py",
>    line 2572, in _constructDomain
>        raise VmError(failmsg)
>    VmError: Creating domain failed: name=xxx
>    --
>    Shaun