[Gluster-devel] close() blocks until flush-behind finishes

[Raghavendra G]

Hi Paul,

The option flush-behind makes only the flush call as background. However it
waits for all the writes to complete, so that it can return the application
errors (if any) happened while syncing them to server. The mail thread you
gave for reference [2] also contains discussion about concerns regarding
flush-behind not waiting till write-syncs are complete and related
explanation.
http://permalink.gmane.org/gmane.comp.file-systems.gluster.user/3361

regards,
Raghavendra.

On Tue, Sep 13, 2011 at 11:59 PM, Paul van Tilburg <paul at luon.net> wrote:

> Hi all,
>
> I have a glusterfs test setup of two servers, each with a brick, that is
> replicated.  Between the two servers there is a bandwidth limit and I
> would like the flush-behind option to handle getting the data to the
> other side asynchronously.  I am using Debian Squeeze with glusterfs
> 3.2.3-1.  Volume setup:
>
>  gluster> volume info
>
>  Volume Name: vol1
>  Type: Replicate
>  Status: Started
>  Number of Bricks: 2
>  Transport-type: tcp
>  Bricks:
>  Brick1: glusterserver.home:/tmp/rep
>  Brick2: glusterclient.home:/tmp/rep
>  Options Reconfigured:
>  performance.write-behind-window-size: 32MB
>  performance.flush-behind: on
>
> However, it seems that when I create a file of 40MB with dd on
> glusterclient.home, the close() system call blocks until everything has
> fully reached glusterserver.home.  This problem has been brought up
> before on the users list[1].  I also recall a discussion, back when
> flush-behind was default off, that making close non-blocking is
> considered to be safe[2].
>
> It seem like I have hit a bug here and would thus like to file a
> report.  Unless I missed something in the configuration/documentation?
>
> Thanks!
>
> Paul
>
> 1: http://www.mail-archive.com/gluster-users@gluster.org/msg01023.html
> 2: http://comments.gmane.org/gmane.comp.file-systems.gluster.user/3152
>
> --
> PhD Student @ Eindhoven                     | email: paul at luon.net
> University of Technology, The Netherlands   | JID: paul at luon.net
> >>> Using the Power of Debian GNU/Linux <<< | GnuPG key ID: 0x50064181
>
> _______________________________________________
> Gluster-devel mailing list
> Gluster-devel at nongnu.org
> https://lists.nongnu.org/mailman/listinfo/gluster-devel
>



-- 
Raghavendra G
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://supercolony.gluster.org/pipermail/gluster-devel/attachments/20110915/2abca3c6/attachment-0003.html>