The Answer Gang

Using FTP, I can easily achieve 10MB/s+ (megabytes per second) to or from the box. The main HDD in the box is a 400GB, 7200RPM, ATA/100 HDD attached to an ATA/133 Promise Controller.

I believe the problem began when I upgraded the box to 2.6.11.

Problem Description:

Sending files to the box via NFS is slow, 1MB/s for a few seconds, nothing, then 2-3MB/s then back to nothing.

Receiving or (pulling) files from the box achieves a sustained transfer rate of 10MB/s+ (megabytes per second).

Boxname = p4box.

p4box (share = /home/myfiles)

If I mount p4box onto another box:

# mount p4box:/home/myfiles /mnt
# cp 1gbfile.txt /mnt

The above process will take forever, stall, lag and etc.

If I mount p4box onto another box:

# mount p4box:/home/myfiles /mnt
# cp /mnt/1gbfile.txt .

I get normal NFS speeds on a 100mbps network.

The problem also occurs in the following scenario:

On p4box (box with the problem):

I:

# mount remote_machine:/disk2 /mnt
# cp /mnt/1gig.txt .

This also does average 1MB/s, but not consistent, it peaks and goes slower and then nothing at all for a while.

If I do the same and copy something to the NFS share (outbound) then it runs at 10MB/s (megabytes per second).

The issue is inbound NFS is VERY slow.

On the affected box:

# Kernel Interface table
Iface   MTU Met   RX-OK RX-ERR RX-DRP RX-OVR   TX-OK TX-ERR TX-DRP TX-OVR Flg
eth0   1500 0   1283895      0      0      0  636062      0      0      0 BMRU
lo    16436 0      1040      0      0      0    1040      0      0      0 LRU

There is clearly no network issue.

REMEMBER: FTP works at full speed in both directions.

# rpcinfo -p l1
    program vers proto   port
     100000    2   tcp    111  portmapper
     100000    2   udp    111  portmapper
     100021    1   udp  32768  nlockmgr
     100021    3   udp  32768  nlockmgr
     100021    4   udp  32768  nlockmgr
     100024    1   udp    831  status
     100024    1   tcp    834  status
     100003    2   udp   2049  nfs
     100003    3   udp   2049  nfs
     100005    1   udp    996  mountd
     100005    1   tcp    999  mountd
     100005    2   udp    996  mountd
     100005    2   tcp    999  mountd
     100005    3   udp    996  mountd
     100005    3   tcp    999  mountd

I've tried rebooting the box, disconnecting/remounting/etc, nothing seems to solve this issue.

I've searched Google and the Web but I have not found anything pertinent to this situation.

Does anyone have any idea what I can try next?

Thanks!

Justin.