Windows 7: Lock pages in memory?

I was doing some benchmarks with Sandra & noticed in Windows 7 that my memory bandwidth was reduced from XP & Vista...but why?

So I looked all the way at the bottom of the bench to see a exclamation with a warning. So I double clicked it & it brought this up.

" Warning W5010 : Cannot use large page memory pages due to lack of privileges.



Fix: Use the Local Security Policy to give yourself lock memory pages privilege.

Large memory pages greatly improve performance when large memory blocks are allocated."


So I gave myself privileges to enable this and was very surprise with the performance increase although I still don't understand what it did & why so much of a memory bandwidth increase...

Screenshots below say it all... from 62% (6497mbs) memory bandwidth efficiency to 65% (6838mbs) with lock pages in memory enabled.

Does anyone here know what this does exactly & can you explain it to me to where I understand if this is a setting that is good or bad to have on for system performance.
Thanks...btw, I have 4Gbs of installed memory on Windows 7 32bit.

This is what the explain tab says

Lock pages in memory

"This security setting determines which accounts can use a process to keep data in physical memory, which prevents the system from paging the data to virtual memory on disk. Exercising this privilege could significantly affect system performance by decreasing the amount of available random access memory (RAM)."

Default: None

Have you noticed an improvement in performance?

Yea, I read all that already (and more) & that says the opposite of what it shows in the benchmarks.
The benchmarks show a marked improvement, but with "Real life" applications & games I don't see any difference in load times or speed increases.

But then again, if you take a bunch of small improvements that's not really noticeable by themselves & put them all together, you got a BIG performance improvement.
That's the reason I take the time to do ALL the OS & software tweaks I know to get the most out of my system.

Still the question remains to why this effects RAM bandwidth, or is this just synthetic & doesn't really effect it at all.