-----Original Message----- From: Mike Kearey [mailto:mkearey@xxxxxxxxxx] Sent: Wednesday, February 28, 2007 12:56 AM To: General Red Hat Linux discussion list Subject: Re: Locking shared memory Allen, Jack wrote: > I do not think the error is because of the first explanation of ENOMEM > So my question is based on the second one. > > Is there a kernel or vm parameter that controls how much memory a > process can utilize? > > I am running RH AS 4.4 32 bit with 2GB of physical memory. > > Thanks in advance: > Jack Allen > G'day Jack, There is memlock limit in shell, changed using the ulimit command from bash. See ulimit -l: $ ulimit -l 32 The actual hard and soft limits are controlled on a Red Hat system using the pam_limits pam module, using the config file /etc/security/limits.conf Check the doc's from RHEL4 for the pam module for details : /usr/share/doc/pam-0.77/txts/README.pam_limits This may well be where the ENOMEM came from, as the default limit that a user may lock memory is 32kB. Cheers, Michael ========================================= Michael: Thanks for the information. Since I do not want all users to have the limit increased for them, I do not want to add and entry in /etc/security/limits.conf. I know it can be done on a per user bases, but any user can start the main database program that creates the shared memory segments. And because the main program runs set UID and the owner of the program is root, it runs as root no matter who starts. I know there are those that think SUID programs to root are dangerous, but we have to have it this way to make things work the way we want it to. It is limited it what it does, in that it does not execute or create files, etc.. arbitrarily, it has very specific things that is does. With that being said what I did was set the resource limit within the program via setrlimit(RLIMIT_MEMLOCK,&rlimit). I set the limit to 1GB and setrlimit returned a success value. But when I try to lock the second 256MB shared memory segment address it still fails the same way. The system has 2GB of memory and there is basically nothing else running on the system other than all the standard/default processes for various services. Do you or anyone else have anymore thoughts as to what may be keeping me from locking the second shared memory segment address? Thank: Jack Allen -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
