Wired Active Inactive Used Free Memory

icerabbit · **Joined:** Mon Nov 29, 2004 9:00 am **Posts:** 21

Looking at the "top" details in terminal I notice that where I thought I always had about 100-150MB RAM free, it actually details like:

PhysMem:
76.4M wired
285M active
142M inactive
505M used
6.62M free

I am reallly curious as to what 76M wired memory means?
as I'd say it has 512 wired.

Why does the inactive amount stay so high? And/or what controls the active / inactive ratio. Keeping an eye on it, it doesn't really change???
I launch additional applications and it hovers around the same numbers.

-- Does a G5 stay at this odd ratio of inactive memory when you add another 512 or 1GB?

Thanks,
icerabbit

eastcoastweb · **Posted:** Thu Apr 28, 2005 9:50 am

I've been wondering this myself. Especially the wired memory....

icerabbit wrote:

Looking at the "top" details in terminal I notice that where I thought I always had about 100-150MB RAM free, it actually details like:

PhysMem:
76.4M wired
285M active
142M inactive
505M used
6.62M free

I am reallly curious as to what 76M wired memory means?
as I'd say it has 512 wired.

Why does the inactive amount stay so high? And/or what controls the active / inactive ratio. Keeping an eye on it, it doesn't really change???
I launch additional applications and it hovers around the same numbers.

-- Does a G5 stay at this odd ratio of inactive memory when you add another 512 or 1GB?

Thanks,
icerabbit

Cory Cooper · **Joined:** Sat Apr 24, 2004 11:50 pm **Posts:** 5400

Here's an explanation from Apple:

Mac OS X: Reading system memory usage in Activity Monitor

Basically:

Wired - Non-cacheable to VM, must stay in RAM
Active - Currently in RAM and being used
Inactive - No longer in use, has been cached to VM
Free - Not be used

If your combination of Free and Inactive is low, you need more RAM.

C

icerabbit · **Joined:** Mon Nov 29, 2004 9:00 am **Posts:** 21

Thanks Cory,

After reading that article it makes sense. Though naming still will be something to get used to ... wired ram, inactive ram? LOL

Guest · **Posted:** Mon May 23, 2005 3:29 pm

Cory Cooper wrote:

Here's an explanation from Apple:

Mac OS X: Reading system memory usage in Activity Monitor

Basically:

Wired - Non-cacheable to VM, must stay in RAM
Active - Currently in RAM and being used
Inactive - No longer in use, has been cached to VM
Free - Not be used

If your combination of Free and Inactive is low, you need more RAM.

C

how much is low?

antarius · **Posted:** Mon May 23, 2005 6:21 pm

Anonymous wrote:

Cory Cooper wrote:

Here's an explanation from Apple:

Mac OS X: Reading system memory usage in Activity Monitor

Basically:

Wired - Non-cacheable to VM, must stay in RAM
Active - Currently in RAM and being used
Inactive - No longer in use, has been cached to VM
Free - Not be used

If your combination of Free and Inactive is low, you need more RAM.

C

how much is low?

I'd say sub 128-256 is low.

I'm running 100% CPU usage, and 6 applications right now (no photo-intensive applications) and I've got ~500MB free+inactive (combined) out of this 1GB total.