Processes in Shared Memory

rmv · October 23, 2009, 9:18am

Hello ,

I would like to know how to check if a given process id belongs to particualr shared memory segment .

Please help

Thanks in advance

Scrutinizer · October 23, 2009, 9:59am

A shared memory segment is not owned by a process but rather is pinned in memory and is owned by a user / group. Multiple processes can access the shared memory segments with the right credentials. You can check the segment and who owns them by typing:

ipcs -ma

as user root.

rmv · October 23, 2009, 10:28am

I realized that the CPID is the creator process id and from there I could
trace all the active processes that are accessing a particular shared memory segment.

Scrutinizer · October 23, 2009, 2:52pm

I see... I would tend to think that from a process' perspective it is not relevant who the CPID is. To find out who are using a shared memory segment I would look at the processes and see what regions they have mapped using a utility like e.g. pmap and/or perhaps info in /proc/pid if you are on a linux system.