[Linux-cluster] GFS2 locking issues

Dennis B. Hopp dhopp at coreps.com
Mon Jun 15 19:00:26 UTC 2009


We have a three node nfs/samba cluster that we seem to be having very
poor performance on GFS2.  We have a samba share that is acting as a
disk to disk backup share for Backup Exec and during the backup
process the load on the server will go through the roof until the
network requests timeout and the backup job fails.

I downloaded the ping_pong utility and ran it and seem to be getting
terrible performance:

[root at sc2 ~]# ./ping_ping /mnt/backup/test.dat 4
       97 locks/sec

The results are the same on all three nodes.

I can't seem to figure out why this is so bad.  Some additional information:

[root at sc2 ~]# gfs2_tool gettune /mnt/backup
new_files_directio = 0
new_files_jdata = 0
quota_scale = 1.0000   (1, 1)
logd_secs = 1
recoverd_secs = 60
statfs_quantum = 30
stall_secs = 600
quota_cache_secs = 300
quota_simul_sync = 64
statfs_slow = 0
complain_secs = 10
max_readahead = 262144
quota_quantum = 60
quota_warn_period = 10
jindex_refresh_secs = 60
log_flush_secs = 60
incore_log_blocks = 1024
demote_secs = 600

[root at sc2 ~]# gfs2_tool getargs /mnt/backup
data 2
suiddir 0
quota 0
posix_acl 1
num_glockd 1
upgrade 0
debug 0
localflocks 0
localcaching 0
ignore_local_fs 0
spectator 0
hostdata jid=0:id=262146:first=0
locktable
lockproto lock_dlm

       97 locks/sec
[root at sc2 ~]# rpm -qa | grep gfs
kmod-gfs-0.1.31-3.el5
gfs-utils-0.1.18-1.el5
gfs2-utils-0.1.53-1.el5_3.3

[root at sc2 ~]# uname -r
2.6.18-128.1.10.el5

Thanks,

--Dennis





More information about the Linux-cluster mailing list