topic Maximum TCP connections per process in Operating System - OpenVMS

Maximum TCP connections per process

Nicolau Roca — Thu, 15 May 2008 06:17:52 GMT

Hi,
how do I know the maximum number of TCP connections per process on OpenVMS?

(I need this information in order to determine the number of dispatcher processes in an Oracle Shared Server configuration)

Thank you,
Nicolau

Re: Maximum TCP connections per process

labadie_1 — Thu, 15 May 2008 06:40:27 GMT

Hello

Fillm sets the maximum number of files and active network logical links.
So it is more or less fillm (and your fillm should be less than CHANNELCNT, the system-wide limit)

Re: Maximum TCP connections per process

Ian Miller. — Thu, 15 May 2008 10:07:36 GMT

and a big enough BYTLM quota to support that

Re: Maximum TCP connections per process

Robert Gezelter — Thu, 15 May 2008 10:28:19 GMT

Nicolau,

I think that we need to go back a step. Are you counting the number of possible connections, or the number of connections that the Oracle client side will establish?

The two are almost assuredly different. For most (single threaded) code, I would suspect that the correct guess would be one per process (should be confirmed from the appropriate Oracle documentation).

- Bob Gezelter, http://www.rlgsc.com

Re: Maximum TCP connections per process

Wim Van den Wyngaert — Mon, 19 May 2008 07:30:25 GMT

To see the maximum number of connections system wide (ucx show comm in the old days) :
ana/sys
SDA> tcpip show inetcb/stat
...
ACT/PEAK/MAX_SOCKET

Will show the maximum (10000 in my case).
See also
http://forums12.itrc.hp.com/service/forums/questionanswer.do?admit=109447627+1211185608007+28353475&threadId=1169204

Wim

Re: Maximum TCP connections per process

Nicolau Roca — Mon, 02 Jun 2008 12:00:47 GMT

Hi,
from Oracle documentation I have seen that each BG device consumes 1472 bytes of the process BYTLM quota.

So un upper limit for the number of concurrent TCP connections for a process is /1472

Thank you all

Regards,
Nicolau

Re: Maximum TCP connections per process

Wim Van den Wyngaert — Mon, 02 Jun 2008 12:25:43 GMT

Also check sysgen channelcnt. It may change the limit downwards ...

Best is to write a program that creates sockets and see how many channels you can open.

Wim