Re: [Moosefs-users] Reserved files remain forever

[Flow J. <fl...@gm...>]

Hi,

I now know how to re-create the issue and it should also be related to 
AutoFS.

I noticed that if I make a new file with non-zero size and delete it 
immediately, it will be set as reserved file and keep at this state for 
a while (about 1 minute in our environment). If the underlying MooseFS 
is unmounted within this short period, the behavior differs between 
fstab mounted FS and AufoFS mounted FS.

* If the FS is mounted by fstab, create and delete a file, then unmount 
the FS, the file eventually gets deleted
* If the FS is mounted by autofs, create and delete a file, then unmount 
the FS, the file remains as reserved forever

And unfortunately we are relying on the timeout feature of AutoFS so 
unmount happens frequently. This is the reason we have so many cache 
files (created then deleted during one mount session) remaining as 
reserved files forever.

Our AutoFS mount option is mentioned in the other thread 
(http://sourceforge.net/mailarchive/forum.php?thread_name=4D68E18F.3000708%40gmail.com&forum_name=moosefs-users). 
And the issue looks like the same:

* If the FS is mounted by fstab, writing a file (> 1M) to some folder 
then unmount it, works O.K.
* If the FS is mounted by autofs, writing a file (> 1M) to some folder 
then unmount it, core file gets dumped

Increasing autofs timeout would help for the reserved file issue but not 
for the core dump issue. And even if the timeout is increased, a restart 
/ power off of the system still won't leave enough time for the file to 
be totally deleted.

I do have a work around to fix the 2 issues temporarily, by mounting the 
entire MFS system with fstab and use "-fstype=bind" option in autofs to 
make auto mounting/unmounting happen. But this is complicated and 
different mfs mount options can't be set with different subfolders. So I 
do hope I can have native AutoFS supported MooseFS mounts.

Can any one help on this?

Many Thanks
Flow

On 02/22/2011 12:03 AM, Flow Jiang wrote:
> Hi,
>
> Just found another issue. I cleared about 10000 reserved files with 
> the script provided at 
> http://sourceforge.net/tracker/?func=detail&aid=3104619&group_id=228631&atid=1075722 
> yesterday, and this morning I had 0 reserved file when started working.
>
> However, after one day development activity with 6 workstations, now 
> we have 204 reserved files not deleted. I've noticed it's stated that 
> "Each session after two hours is automatically closed and all the 
> files are released." in above link, but seems it's not happening in 
> our environment. We have CentOS 5.5 x86 servers and run mfsmount on 
> Fedora 12 x64 workstations. Both servers and workstations run mfs 
> 1.6.19. And mfs is serving as home with read / write access.
>
> Here are some example of the reserved files by reading the metadata:
>
> 00067856|UserHome|tompan|.mozilla|firefox|mk9e32d7.default|OfflineCache|index.sqlite-journal 
>
> 00067857|UserHome|tompan|.mozilla|firefox|mk9e32d7.default|OfflineCache|index.sqlite-journal 
>
>
> Most of the 204 reserved files look like temp / journal files.
>
> Any ideas about the cause of the issue?
>
> BTW, OpenOffice fails to start if MFS serves as home directory. It 
> should be a FS bug as stated on: 
> http://qa.openoffice.org/issues/show_bug.cgi?id=113207. Would it be 
> related to the issue above? And can we fix this OOo issue?
>
> Many Thanks
> Flow
>
>
>
>
>
>
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