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Shuh · Nov 7, 2002, 10:47 PM

In the last UNIX shop I used to work in, we were logged on for months on the same UNIX workstations. At times, memory would be bogged down with all sorts of indigenous processes and cruft.

So we would run a little command-line utility that would grab real-memory and have the OS push all the unused crap to VM. Then we would have room in RM to run our stuff. Anyone know about something like that for OSX?

Arkham_c · Nov 12, 2002, 04:05 PM

I whipped up a little app to do just this. It allocates more and more RAM until you stop it. It's called "Memory Hog" and can be downloaded (along with the source code) here:

http://software.theresistance.net/

Shuh · Nov 19, 2002, 01:28 PM

Thank you! This is just what someone using OSX needs when [s]he has a session with a few months uptime and a lot of cruft that would be better off paged to VM!

absmiths · Nov 21, 2002, 12:55 PM

I guess I don't see the utility. If an app has been idle for several months, it will be paged by now (unless your whole system is idle). The only thing hogging memory will accomplish is pushing active pages to the store which will probably be activated again when your hog finishes.

Unless what you are doing is temporarily pushing active pages to the store so that you can run a program which would be adversely affected by paging during its' operation.

OreoCookie · Nov 21, 2002, 04:51 PM

Well, I don't know about OS X, but Linux allows overcommitting, i. e. allowing apps to allocate more memory than available (because most apps won't use that much).

But OS X's memory management is advanced enough to push �old' apps into the VM by itself, except there is some wired memory (memory allocated and used by an application that explicitly wants to have �real' RAM). But in that, allocating memory won't push this memory into VM, either.

I have never had that problem with OS X, btw, opposed to the AlphaStation at work (just 256 MB are allowed per process -- bad news for me, my simulations eat up at least 300 MB, and growing). The kernel has to be replaced so that I would finally be able to run my simulations on it. But yeah well, there is always the Linux cluster ...