kernel memory tunables

Chuck Swiger cswiger at
Wed Jan 18 09:05:55 PST 2006

Michael Barnett wrote:
> I am trying to figure out which system tunables determine memory  
> resource usage by the amount of available physical memory in the box  so 
> i can hard code sane values on a system with a lot of memory.

If the machine is properly configured, getrlimit(RLIMIT_DATA, ...) is a 
reasonable starting place.  The amount of memory available to an individual 
process may well be less than the total amount of RAM installed, especially on 
32-bit machines using PAE to have more than 4GB of RAM.

Otherwise, consider using the sysctl interface to look at hw.usermem...


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