Ram usage question

[Kirk Gittings]

I have a new computer, Quad Core 2 with 8 gigs of ram. Question for the computer wizards?

I installed one of these CPU and Ram usage monitors. I then ran through my normal PS workflow to see what happened on the monitor. With up to 5 large files open with as many as 12 layers, running very memory intensive procedures like Photomerge and Lens Correction, I never saw the memory usage rise above 51%, even with other programs running in the background. This is with a RAM allocation in PS at 70%, 30 History States, cache level 4.

What does this 51% RAM usage tell me, if anything, about how I should adjust my Performance settings in PS?

[Preston]

Kirk,

What does the user guide for the usage monitor say about what the data reveals? Without knowing the specific monitoring program, it's tough to tell what the 51% figure actually means.

-Preston

[Jeff Conrad]

What does PS show for scratch size? I assume you're running CS4 under a 64-bit OS.

[Mike1234]

First, as Jeff asks, do you have a 64 bit OS and 64 bit PS? Second, what does your System Information indicate reagrding your RAM (how much)? Lastly, have you tried setting your PS Preferences to 85 or 90 percent and checked the monitor again?

One more question... how large are the PS files and what filters are you using?

[Ed Richards]

It means you have enough memory. Do not raise you PS allocation above 70%, it can lead to real slow downs. There is a lot going out in the OS that PS depends on. Be happy!

[Mike1234]

PS will only use "available" RAM. I set mine to 85 percent but I close PS when I need other applications.

[Greg Miller]

Kirk - you are fine. Since you have PS set to use 70% of memory, if your PS maxed out, your monitor would show total memory usage at 85%+ (the additional used by the OS and any other apps that are running).

As with most things computer once you reach 90% utilization or more of a resource, you will see significant performance degradation. At 50% total memory utilization, you are in a comfort zone with room to spare.

70% for PS is a general sweet spot. You could try to tweak that a bit but you won't see any appreciable performance gains based on the numbers that you report. If you allocate more than that, you will start to starve other apps for memory, including the OS, and that usually has a way to come back and hurt PS too.

[Kirk Gittings]

First, as Jeff asks, do you have a 64 bit OS and 64 bit PS? Second, what does your System Information indicate reagrding your RAM (how much)? Lastly, have you tried setting your PS Preferences to 85 or 90 percent and checked the monitor again?

One more question... how large are the PS files and what filters are you using?

Yes I have a 64 bit OS and 64bit PS. I haven't tried setting Pref higher than 70%.

Files go up to about 200GB+ plus layers. Just for fun I ran things like lens correction that is very resources hungry.

[Kirk Gittings]

Kirk - you are fine. Since you have PS set to use 70% of memory, if your PS maxed out, your monitor would show total memory usage at 85%+ (the additional used by the OS and any other apps that are running).

As with most things computer once you reach 90% utilization or more of a resource, you will see significant performance degradation. At 50% total memory utilization, you are in a comfort zone with room to spare.

70% for PS is a general sweet spot. You could try to tweak that a bit but you won't see any appreciable performance gains based on the numbers that you report. If you allocate more than that, you will start to starve other apps for memory, including the OS, and that usually has a way to come back and hurt PS too.

Thanks Greg. I have noticed that the CPU occasionally maxes out very briefly during some proceses. I mean it hits max for a very brief instant and then goes down again.

[Ed Richards]

CPU maxing out is fine. What are you doing that generates 200gb files? If you can handle several of those your system is amazing.