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 25/04/13 10:35, Roger Pau Monné wrote:
> 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

And the number of free pages keep in blkback cache:

# echo 256 > /sys/module/xen_blkback/parameters/max_buffer_pages