[Gluster-users] question about info and info.tmp

[Atin Mukherjee]

On Fri, Nov 11, 2016 at 8:33 AM, songxin <songxin_1980 at 126.com> wrote:

> Hi Atin,
>
> Thank you for your reply.
> I have two questions for you.
>
> 1.Are the two files info and info.tmp are only to be created or changed in
> function glusterd_store_volinfo()? I did not find other point in which the
> two file are changed.
>

If we are talking about info file volume then yes, the mentioned function
actually takes care of it.


> 2.I found that glusterd_store_volinfo() will be call in many point by
> glusterd.Is there a problem of thread synchronization?If so, one thread may
> open a same file info.tmp using O_TRUNC flag when another thread is
> writing the info,tmp.Could this case happen?
>

 In glusterd threads are big lock protected and I don't see a possibility
(theoretically) to have two glusterd_store_volinfo () calls at a given
point of time.


>
> Thanks,
> Xin
>
>
> At 2016-11-10 21:41:06, "Atin Mukherjee" <amukherj at redhat.com> wrote:
>
> Did you run out of disk space by any chance? AFAIK, the code is like we
> write new stuffs to .tmp file and rename it back to the original file. In
> case of a disk space issue I expect both the files to be of non zero size.
> But having said that I vaguely remember a similar issue (in the form of a
> bug or an email) landed up once but we couldn't reproduce it, so something
> is wrong with the atomic update here is what I guess. I'll be glad if you
> have a reproducer for the same and then we can dig into it further.
>
> On Thu, Nov 10, 2016 at 1:32 PM, songxin <songxin_1980 at 126.com> wrote:
>
>> Hi,
>> When I start the glusterd some error happened.
>> And the log is following.
>>
>> [2016-11-08 07:58:34.989365] I [MSGID: 100030] [glusterfsd.c:2318:main]
>> 0-/usr/sbin/glusterd: Started running /usr/sbin/glusterd version 3.7.6
>> (args: /usr/sbin/glusterd -p /var/run/glusterd.pid --log-level INFO)
>> [2016-11-08 07:58:34.998356] I [MSGID: 106478] [glusterd.c:1350:init]
>> 0-management: Maximum allowed open file descriptors set to 65536
>> [2016-11-08 07:58:35.000667] I [MSGID: 106479] [glusterd.c:1399:init]
>> 0-management: Using /system/glusterd as working directory
>> [2016-11-08 07:58:35.024508] I [MSGID: 106514]
>> [glusterd-store.c:2075:glusterd_restore_op_version] 0-management:
>> Upgrade detected. Setting op-version to minimum : 1
>> *[2016-11-08 07:58:35.025356] E [MSGID: 106206]
>> [glusterd-store.c:2562:glusterd_store_update_volinfo] 0-management: Failed
>> to get next store iter *
>> *[2016-11-08 07:58:35.025401] E [MSGID: 106207]
>> [glusterd-store.c:2844:glusterd_store_retrieve_volume] 0-management: Failed
>> to update volinfo for c_glusterfs volume *
>> *[2016-11-08 07:58:35.025463] E [MSGID: 106201]
>> [glusterd-store.c:3042:glusterd_store_retrieve_volumes] 0-management:
>> Unable to restore volume: c_glusterfs *
>> *[2016-11-08 07:58:35.025544] E [MSGID: 101019]
>> [xlator.c:428:xlator_init] 0-management: Initialization of volume
>> 'management' failed, review your volfile again *
>> *[2016-11-08 07:58:35.025582] E [graph.c:322:glusterfs_graph_init]
>> 0-management: initializing translator failed *
>> *[2016-11-08 07:58:35.025629] E [graph.c:661:glusterfs_graph_activate]
>> 0-graph: init failed *
>> [2016-11-08 07:58:35.026109] W [glusterfsd.c:1236:cleanup_and_exit]
>> (-->/usr/sbin/glusterd(glusterfs_volumes_init-0x1b260) [0x1000a718]
>> -->/usr/sbin/glusterd(glusterfs_process_volfp-0x1b3b8) [0x1000a5a8]
>> -->/usr/sbin/glusterd(cleanup_and_exit-0x1c02c) [0x100098bc] ) 0-:
>> received signum (0), shutting down
>>
>>
>> And then I found that the size of vols/volume_name/info is 0.It cause
>> glusterd shutdown.
>> But I found that vols/volume_name_info.tmp is not 0.
>> And I found that there is a brick file vols/volume_name/bricks/xxxx.brick
>> is 0, but vols/volume_name/bricks/xxxx.brick.tmp is not 0.
>>
>> I read the function code glusterd_store_volinfo () in glusterd-store.c .
>> I know that the info.tmp will be rename to info in function
>> glusterd_store_volume_atomic_update().
>>
>> But my question is that why the info file is 0 but info.tmp is not 0.
>>
>>
>> Thanks,
>> Xin
>>
>>
>>
>>
>> _______________________________________________
>> Gluster-users mailing list
>> Gluster-users at gluster.org
>> http://www.gluster.org/mailman/listinfo/gluster-users
>>
>
>
>
> --
>
> ~ Atin (atinm)
>
>
>
>
>



-- 

~ Atin (atinm)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.gluster.org/pipermail/gluster-users/attachments/20161111/8cb024f7/attachment.html>