Newsgroups: comp.parallel.pvm
From: chiggins@ccvax.ucd.ie
Subject: Problem with PVM 3.3.7 on SPARC multiprocessor platform
Organization: University College Dublin
Date: 3 May 95 10:26:40 WET
Message-ID: <1995May3.102640.58740@ccvax.ucd.ie>

Hi,

I too am experiencing difficulties with PVM 3.3.7 on a 2 processor SPARC
station running SunOS 5.3. 

A simple code to iniate a number of tasks which write out their tid's and
exit hangs intermittently. Usually it hangs just after all the slave
tasks have called pvmfexit and before the Master completes it's
call to pvmfexit. However sometimes this code runs to completion with 	
no problems. 

My only idea at the moment is to implement a change suggested in the file
$PVM_ROOT/Readme.mp.

Running adb as described shows a limit on the number of shared memory 
segments ( and therefore the total number of PVM processes that can run 
at one time) for the host. This is currently set to 6, which is 
apparently the default.
Sun Microsystems have indicated that this can be changed by the systems	
administrator however the precise details of how to do so are not given
in the Readme.mp. 

Can anyone provide me with the details of how to increase the limit on the
number of shared memory segments a process can attach to please ?

Thanks,


Colum Higgins                             Email : higgins@irlearn.ucd.ie
Supercomputing Support               NEW! Tel.  : 353-1-706 2497
Computing Services                        Fax   : 353-1-283 7077
University College Dublin
Dublin 4
Ireland

ps. Here is the exact output from adb:

 adb -k /dev/ksyms /dev/mem
physmem 1e19
shminfo,4/D
shminfo:
shminfo:        1048576         1               100             6
                                                                _

