Use ifconfig to check the MTU on your eth device
If it is bigger than 1500 than u use jumbo.
You will need to check on the switch as well.
Make sure all the MTU's in your path are the same.
You can also check the mss (MTU-headers) 

-----Original Message-----
From: [mailto:[EMAIL PROTECTED]
On Behalf Of Miguel Gonzalez Casta?os
Sent: Wednesday, January 09, 2008 1:07 PM
Subject: Re: Performance of open-iscsi over TCP

> 10 MB/sec sounds really poor.
> What kind of disk performance do you get locally on the target/server 
> from the SATA RAID array? You can try iometer or some other disk
benchmarking tools.
I've downloaded iometer, can you tell me what do I have to test and how?
> What kind of latency (ping roundtrip with 4k packets) do you have from

> the initiator to the target? latency is one of the key factors 
> limiting IOPS you will get.
ping -s 4048

4056 bytes from icmp_seq=179 ttl=128 time=0.795 ms

--- ping statistics ---
179 packets transmitted, 178 received, 0% packet loss, time 178261ms rtt
min/avg/max/mdev = 0.789/1.429/1.990/0.534 ms

> How's your network between the target and initiator? gigabit? jumbo
> flow control? what kind of switch are you using?
gigabit in both ends. The switch I'm not in front of the machine so I
can't tell you until next week but my guess is that's a regular switch. 
I think that I'm going to try a crossover cable of CAT 6 to avoid any
other issue. I think jumbo frames are deactivated but how can I know?
> How's the performance with FTP/HTTP/CIFS between the target and the 
> initiator?
It is the same as mentioned before: 10 MB/s


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