[Ocfs2-devel] disk full when it shouldn't

[Tao Ma <tao.ma@oracle.com>]

Hi Massimo,
Massimo Cetra wrote:
> Il 09/11/2010 02:06, Tao Ma ha scritto:
>> Hi Massimo,
>>
>> From the output, it seems that you shouldn't meet with ENOSPC problem
>> at that time. So when you meet with ENOSPC, could you please do 'sync'
>> first(that will sync the metadata to the disk so that stat_sysdir can
>> output the real metadata info) and then do stat_sysdir?
>>
>> btw, you can also try to 'touch' one new file in your ocfs2 volume. So
>> if it succeeds, it means that the inode_alloc is ok. Otherwise, your
>> inode_alloc has no space. Please also try this test when you meet with
>> ENOSPC.
>
> Hi Tao,
>
> As i supposed, the problem arose another time.
>
> Attached you may find the stat_sysdir output.
Got it.
>
>
> For the sake of completeness, have to say that:
>
> - The output of df was the following:
>
> # df -i
> Filesystem             Inode   IUsati  ILib. IUso% Montato su
> [CUT]
> /dev/drbd2           9174751 4695156 4479595   52% /var/mail
>
> # df
> Filesystem        blocchi di   1K   Usati Disponib. Uso% Montato su
> [CUT]
> /dev/drbd2            36699004  18780656  17918348  52% /var/mail
I have to say that df is only an approximate way to get the real info of 
an ocfs2 volume.
df -i use statfs(2). And since there is no easy way to calculate all the 
inodes without
locking every node's inode allocator, it just searchs the global_bitmap 
and gives a rough number.

>
> The filesystem was not full:
>
> sheet3-1:/var/mail/virtual# dd if=/dev/zero of=TEST bs=1024 count=1024
> dd: scrittura di `TEST': No space left on device
> 1009+0 records in
> 1008+0 records out
> 1032192 bytes (1,0 MB) copied, 0,454305 s, 2,3 MB/s
> sheet3-1:/var/mail/virtual#
So this is node2? From the stat_sysdir output you attached, 
inode_alloc:0001 is full.
It has no free inodes and the creation will fail.

So you are meeting with the problem of fragmentation. Discontig block 
group should fix it.

Regards,
Tao