Quick question regarding commit memory and pagefile

OMNIOMEGA10 · 17 Sep 2011

I recently disabled my pagefile to see how it would affect the total commit usage in task manager. I have noticed that the commit usage is higher than the ram usage. Does this mean that Windows is paging to the SSD/HDD anyway? So in effect, if there is 300MB paged elsewhere, I can't use all 8GB of ram I assume, since going over the commit total (which seems to match my total ram) would lead to memory exhaustion, even if the ram is not used up.
Heres what task manager shows after login:
Physical Memory
Total: 8189MB
Cached: 1285MB
Available: 6826MB
Free: 5640MB
Used: 1340MB

Kernal Memory
Paged: 140MB
Nonpaged: 88MB
The commit shows 1628/8187 (used/total), pagefile disabled.
Is this the reason why pagefile should be left on?

OMNIOMEGA10 · 17 Sep 2011

Lol now I realise why. By adding Kernal and Physical Memory Used, you get the total commit used. Jeez, I must be brain dead.

OMNIOMEGA10 · 17 Sep 2011

Although that still doesn't explain why Windows reports 6826MB available ram if Kernel Memory is using it (maybe kernel memory is hidden in the 'free space')... Also 1340+140+88=1568, which falls short by 60 compared to the 1628 commit usage.

MilesAhead · 17 Sep 2011

Best explanation I found so far is for XP but it may shed some light:

Windows Task Manager - Performance Explained | PCWizKids Tech Talk - Configure your Gaming Rig and Tweak Windows for Performance

It was my impression that since code images act as their own page file, that the kernel "paged out" could be misleading. Since it should not have to be stored when it can be just read in again off the drive. Even when I run no swap file it always shows some kernel memory paged out.

If there's a system guru around please chime in as it's not easy to find definitions for some of this stuff. :)

logicearth · 18 Sep 2011

See Part One.
https://msmvps.com/blogs/gdicanio/ar...ssinovich.aspx

No better person to get this information from then Mark Russinovich.

OMNIOMEGA10 · 18 Sep 2011

Thanks for that link. Very detailed!
Considering that Commit is total ram and pagefile memory combined, and I don't have a pagefile, does that mean my ram usage is actually 1628MB, not 1340MB (as reported by all the ram usage monitors)? Does this also mean my ram available is 6561MB, not 6826MB? I'm still a bit confused.

karlsnooks · 19 Sep 2011

| RESMON | ENTER | MEMORY tab

lhorwinkle · 24 Sep 2011

logicearth said:

No better person to get this information from then Mark Russinovich.

Good advice. Russinovich (and Jeff Richter and others from the original NT-series design team) knows what he's talking about. Others (especially online) do not. The web contains a torrent of misinformation on these subjects. Ignore all of that.

Yes, there are a few experts who know what they're talking about. But there are also experts who are clueless, despite their fame, their putative credentials, and their online (false) reputation. Ignore them.

Simple rule: Read Russinovich. Ignore the rest.

**cluberti** · 24 Sep 2011

Also, don't use Task Manager for determining resource consumption - it uses terms that are not entirely correct when describing memory usage, and resmon or perfmon are much better (for example, committed in Task Manager != actual committed memory, it actually also includes other counters that can skew the results (for example, the commit column in task manager includes *reserved* memory, that hasn't actually been committed).

Task manager is for managing tasks in Windows 7 (and higher), and Resource Monitor (resmon) is for determining actual resource usage (short of using perfmon, Process Explorer, or the tools in the WPT).