On Wed, Mar 23, 2005 at 11:04:40AM -0600, Miller, Ryan wrote:
> Here's a question from one of my cohorts, since this is our first try at 
> this, I thought I would see if I could get any input from anyone else doing 
> this.
>
> We have been testing jumbo frames(8990) using TSM on an AIX client. The base 
> line test with MTU of 1500 moved 22G in 44 minutes. Changing the MTU to 8990 
> and the TCP receive and send buffer sizes on both the mainframe and AIX 
> client to 256K, the same 22G of data takes 1 hour and 40 minutes.
>
> Also the largest input packet size is 8192, not 8940. Are their any tcp 
> parameters to se on the client that would help with the jumbo frame transfer 
> time?

How are your Mainframe and client connected together?  Does your switch/router
hardware support jumbos?  All devices on the network should support jumbo
frames, non jumbo routers will need to break the frames back down again.  There
is no real standard for jumbo frames, and we can't use them on our gear *yet*,
so that is why I am asking.

Bob