Re: [GIT PULL] (xen) stable/for-jens-3.10 xenwatch: page allocation failure: order:7, mode:0x10c0d0

["Roger Pau Monné" <roger.pau@citrix.com>]

On 24/04/13 20:16, Sander Eikelenboom wrote:
> Friday, April 19, 2013, 4:44:01 PM, you wrote:
> 
>> Hey Jens,
> 
>> Please in your spare time (if there is such a thing at a conference)
>> pull this branch:
> 
>>  git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git stable/for-jens-3.10
> 
>> for your v3.10 branch. Sorry for being so late with this.
> 
> <big snip></big snip>
> 
>> Anyhow, please pull and if possible include the nice overview I typed up in the
>> merge commit.
> 
>>  Documentation/ABI/stable/sysfs-bus-xen-backend |  18 +
>>  drivers/block/xen-blkback/blkback.c            | 843 ++++++++++++++++---------
>>  drivers/block/xen-blkback/common.h             | 145 ++++-
>>  drivers/block/xen-blkback/xenbus.c             |  38 ++
>>  drivers/block/xen-blkfront.c                   | 490 +++++++++++---
>>  include/xen/interface/io/blkif.h               |  53 ++
>>  6 files changed, 1188 insertions(+), 399 deletions(-)
> 
>> Roger Pau Monne (7):
>>       xen-blkback: print stats about persistent grants
>>       xen-blkback: use balloon pages for all mappings
>>       xen-blkback: implement LRU mechanism for persistent grants
>>       xen-blkback: move pending handles list from blkbk to pending_req
>>       xen-blkback: make the queue of free requests per backend
>>       xen-blkback: expand map/unmap functions
>>       xen-block: implement indirect descriptors
> 
> 
> Hi Konrad / Roger,
> 
> I tried this pull on top of latest Linus latest linux-3.9 tree, but although it seems to boot and work fine at first, i seem to get trouble after running for about a day.
> Without this pull it runs fine for several days.
> 
> Trying to start a new guest I ended up with the splat below. In the output of xl-dmesg i seem to see more of these than before:
> (XEN) [2013-04-24 14:37:40] grant_table.c:1250:d1 Expanding dom (1) grant table from (9) to (10) frames

Hello Sander,

Thanks for the report, it is expected to see more messages regarding
grant table expansion with this patch, since we are using up to 1056
persistent grants for each backend. Could you try lowering down the
maximum number of persistent grants to see if that prevents running out
of memory:

# echo 384 > /sys/module/xen_blkback/parameters/max_persistent_grants

This will set the maximum number of persistent grants to the previous value.