I want to use mlock to lock portions of my application process into memory, so it doesn't get swapped out. I would like to "mlock" the text segement, data segment, BSS segment and heap segment of my application process - how do I find the start address and length of each of these 4 segments of my application process?

Thanks in advance for your help...

Have you considered running a system that has no swap space?

No, I haven't thought of that before. Is that fairly easy to configure/setup?

Don't try to do that ... anyway, you can't. An application can "wire" a few pages into memory, maybe, but you can't make an entire application non-swappable.

If you're worried about this sort of thing .. buy more RAM, and/or run fewer applications in the system. Or impose "ulimit"s on what the individual applications can potentially allocate.

The system will never steal a page unless it's been reduced to stealing in order to survive. If you can demonstrate that your application is being adversely affected by swapping, then the root cause to be dealt-with is not a microscopic one but a much bigger picture.

At install time you get prompted to define a swap partition (or logical volume if you lean that way). After installation while running normally you remove the swap line from /etc/fstab and reboot. You now have a spare partition you can repurpose.

Then all your processes will refrain from any paging/swapping with no extra effort.

Thanks for all of the advice. At this point, I'm only interested in locking/pinning certain segments of an applicaiton into memory using the mlock function. However, I'm not sure how to find out the starting address and length of each segment. It appears to be available in kernel space via the mm_struct, but not sure how to access that information in the application itself?

#sundialsvcs - I'm curious to understand why you believe that an entire application can't be "wired" into memory and made non-swappable? Thanks