On Gwe, 2004-05-28 at 20:43, Janek Jakubek wrote: > We had a TCPIP performance issue when we upgraded from > OS/390 2.7 to 2.10. The conclusion of that the problem is attached > below (from an IBM ETR record). > This could be another lead to follow ....
Except that the problem occurs with an 8K MTU where you would be streaming 8K chunks , unless the latency of the link is horrible in which case you should check the zOS TCP stack supports the window scale feature. If not then you might want to remind your vendor that its not exactly "new". With large windows you can use more buffer space to hide the latency problem. Normally this applies to satellite links but if VM is having to thrash between guest OS's maybe there are similar issues. Be careful turning Nagle off btw - while it may improve individual throughput on a network as opposed to point to point hop it can lead to some really horrible network and stack inefficiencies. ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390