Configuring tcp window scaling on a 32 way Superdome?

[Michael Zoeller]

I need to configure a 32 way Superdome running HP-UX 11.23 to use tcp window scaling. I need to set it as close as possible to the way the customers Sun box is configured. The Sun has a max window of 450K. How / what do I change to enable this on the Superdome. I think I need the ndd command but can not find much on what each of the tcp setting are for (ie. which ones I need to set)

[RAC_1]

ndd -h supported will give the list of the ndd parameters supported.

I think you are looking for tcp window size parameter.
Look at the folloing.
tcp_recv_hiwater_def - Maximum receive window size
tcp_recv_hiwater_lfp - Maximum receive window size for fast links
tcp_recv_hiwater_lnp - Maximum receive window size for slow links


ndd -h cp_recv_hiwater_def

Anil

[Sundar_7 · Accepted solution]

http://www2.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000071549498

A good document on TCP buffer size parameters.

[rick jones]

ftp://ftp.cup.hp.com/dist/networking/briefs/annotated_ndd.txt

Of course, there is also the old standby of applications making setsockopt() calls directly so they do not depend on system configuration :)

What sort of data transfer are you doing where you need a 450KB window?

[Michael Zoeller]

Only information I have is the customer has a DS3 link between Here (east coast) and the west coast. Thanks to all who answered I think I have what I need.