10.7.2 - virtual memory, nom nom nom

The only thing you need to watch is page outs, which indicate you've maxed out your RAM. To determine if you can benefit from more RAM, launch Activity Monitor and click the System Memory tab at the bottom to check your page outs. Page outs are cumulative since your last restart, so the best way to check is to restart your computer and track page outs under your normal workload (the apps, browser pages and documents you normally would have open). If your page outs are significant (say 1GB or more) under normal use, you may benefit from more RAM. If your page outs are zero or very low during normal use, you probably won't see any performance improvement from adding RAM.

Mac OS X: Reading system memory usage in Activity Monitor

To see which apps are consuming system resources, Launch Activity Monitor and change "My Processes" at the top to "All Processes", then click on the CPU column heading once or twice, so the arrow points downward (highest values on top). Also, click on the System Memory tab at the bottom. Then take a screen shot, scroll down to see the rest of the list, take another screen shot and post them.

 

"Inactive" memory is effectively "free" (it will be reclaimed if other apps need it).

Inactive memory can be retained for use by apps that may need to reference it until it is needed for something else. An example of this i see all the time is inactive memory caused by VMware Fusion's use as disk cache for virtual machines.

AS above, just keep an eye on the page-outs (more importantly, the rate/sec) and ignore the blue section of the graph. Consider the blue section (inactive) the same as "free".

"Free" memory on a modern system that uses virtual memory and buffer cache is WASTED memory. It is doing nothing to improve performance, whilst "inactive" memory may help (and is reclaimed if needed anyway).

"VM" size has nothing to do with real memory usage, it is virtual address space provided to applications.

VM size will be large on lion/64 bit systems because OS X provides a much larger virtual address space in this situation. It doesn't actually allocate the "VM" size of memory....

 

It's also due to a bug in OS X. Adam Fields has a write up on the issue.

 

I much prefer the aesthetics of Mac OS X. It's just enjoyable to use. But I have to say that Windows 7 performs better in my experience. Believe it or not, Windows 7 is snappier running in Parallels than native Lion on the same machine!

I really believe it all comes down to the virtual memory problem that has been exacerbated in Lion -- it just kills performance. Has anyone noticed any improvements in this area in Mountain Lion?

 

Memory oage out enormous

Hi,

On my MacBookPro 4Gb 2.4GHz IntelCorei7 (2011) I have OSX10.7.5

I am experiencing big performance problems and I feel it is the memory usage. Page out and Swap usage are 8Gb and 7.7Gb respectively. These overloads are very frequent and I need to restart the system to reset this, although with normal use it goes up again in a few hours work.

Intensive use of some applications that rely on memory such as Mac(I tested the same things I do with a regular linux workstation with same memory and worst graphics card).

At MacStore they recomended me to upgrade to 10.8, is that the solution I need?