[Lustre-discuss] Number of inodes on OST

[Chan Ching Yu Patrick]

Hi all,

I found that when I create a file, the number of inodes on OST does not 
increase.

Let's see the following experiment:

[root at client lustre]# lfs df -i
UUID                      Inodes       IUsed       IFree IUse% Mounted on
data-MDT0000_UUID         524288        3428      520860   1% /lustre[MDT:0]
data-OST0000_UUID         393216        2398      390818   1% /lustre[OST:0]
data-OST0001_UUID         393216        2398      390818   1% /lustre[OST:1]

filesystem summary:       524288        3428      520860   1% /lustre


[root at client lustre]# dd if=/dev/zero of=/lustre/file12 bs=1M count=1000
1000+0 records in
1000+0 records out
1048576000 bytes (1.0 GB) copied, 46.4868 s, 22.6 MB/s


[root at client lustre]# lfs df -i
UUID                      Inodes       IUsed       IFree IUse% Mounted on
data-MDT0000_UUID         524288        3429      520859   1% /lustre[MDT:0]
data-OST0000_UUID         393216        2398      390818   1% /lustre[OST:0]
data-OST0001_UUID         393216        2398      390818   1% /lustre[OST:1]

filesystem summary:       524288        3429      520859   1% /lustre


You can see the number of inodes on MDT is increased by 1. But the 
number of inodes on OST keep unchanged.


According to Lustre Manual, the inodes on OST should increase.

"Each time a file is created on a Lustre file system, it consumes one 
inode on the MDT and one inode for each OST object over which the file 
is striped. "


Anyone knows why?   Thanks very much.

Regards,
Patrick