[Gluster-users] GlusterFS Slow Performance In One Direction

[Jeffery Soo]

Here's my setup. I have 2 servers with the exact hardware and OS 
configuration.
Each server is also a client.  I've tried to do a "DRBD" style setup 
using GlusterFS.

Let's say I have gluserfs mounted on /mnt/gluster

On Remote 1's shell I issue this command:

cp /mnt/gluster/test1000mbfile /mnt/gluster/test100mbfile--

The transfer rate to Server 2 reaches about 30-40 MB/s.

The problem is if I do this same thing on Server 2, the transfer rate to 
Server 1 is only about 10-15 MB/s
Does anyone have any idea what is causing the slow performance from 
Server 2 to Server 1?

Server 2 is capable of sending at 40MB/s to Server 1 in an SCP transfer, 
so I've ruled out network or hardware issues.

=====================================================

Both servers have the same glusterfsd.vol and glusterfs.vol files:

Client File:

+------------------------------------------------------------------------------+
  1: volume remote1
  2:   type protocol/client
  3:   option transport-type tcp
  4:   option remote-host xx.xx.xx.xx
  5:   option remote-subvolume brick
  6: end-volume
  7:
  8: volume remote2
  9:   type protocol/client
 10:   option transport-type tcp
 11:   option remote-host xx.xx.xx.xx
  17:   option remote-subvolume brick
 18: end-volume
 19:
 20: volume replicate
 21:   type cluster/replicate
 22:   subvolumes remote1 remote2
 23: end-volume
 24:
 25: volume writebehind
 26:   type performance/write-behind
 27:   option window-size 1MB
 28:   subvolumes replicate
 29: end-volume
 30:
 31: volume cache
 32:   type performance/io-cache
 33:   option cache-size 512MB
 34:   subvolumes writebehind
 35: end-volume

Server
=================
  1: volume posix
  2:   type storage/posix
  3:   option directory /data/export
  4: end-volume
  5:
  6: volume locks
  7:   type features/locks
  8:   subvolumes posix
  9: end-volume
 10:
 11: volume brick
 12:   type performance/io-threads
 13:   option thread-count 8
 14:   subvolumes locks
 15: end-volume
 16:
 17: volume server
 18:   type protocol/server
 19:   option transport-type tcp
 20:   option auth.addr.brick.allow *
 21:   subvolumes brick
 22: end-volume