All:

I have 4 systems that have plenty of RAM to run XP without a swap file. I use these systems only for R@H and most of them are P4 with HT and 1.25GB of RAM.

Should I expect to see much of an improvement in crunching when I disable the page file? I would assume the process is fairly efficient but the disks are so much slower than RAM that I expect to see an improvement.

Does anyone know of any issues with no page file and BOINC? What problems should I expect?

thx

---

Thx!

Paul

As long as they are dedicated crunchers and your BOINC preferences are set correctly, you can run no pagefile just fine. Correct settings for your circumstance would include:

Leave applications in memory while suspended? no
Write to disk at most every 300 seconds
Use at most 0% of page file (swap space)
Use at most 25% of memory when computer is in use
Use at most 50% of memory when computer is not in use

You're welcome to increase the last two values as needed, just be careful not to set the last one beyond 75%. I.e., the operating system should have at least 512M left to do everything else.

In theory, your machine in your situation will run no faster without a page file then with one. Because, as you describe it, you never need to write anything out to the page file. Windows is aware of the reletive speed of disk vs RAM and so avoids using the page file when possible.

However, if anything should come up that would cause your machine to use more memory, even only temporarily, it's not going to have any way to handle the situation... and I believe crash Windows.

So, it is possible to run with no page file. But, in your case, having one would be sort of an insurance policy.

I would suggest you push up the setting for how often to write to disk to 10 or 15 minutes, and go in to the setup for the machine and set the disk to power down when idle.

The only time I've heard of people setting things with no page file is when they are truely running a diskless machine.

---

Rosetta Moderator: Mod.Sense

In theory, your machine in your situation will run no faster without a page file then with one. Because, as you describe it, you never need to write anything out to the page file. Windows is aware of the reletive speed of disk vs RAM and so avoids using the page file when possible.

However, if anything should come up that would cause your machine to use more memory, even only temporarily, it's not going to have any way to handle the situation... and I believe crash Windows.

So, it is possible to run with no page file. But, in your case, having one would be sort of an insurance policy.

I would suggest you push up the setting for how often to write to disk to 10 or 15 minutes, and go in to the setup for the machine and set the disk to power down when idle.

The only time I've heard of people setting things with no page file is when they are truely running a diskless machine.

There is some debate by enthusiast power users whether a pagefile is necessary in these cases. Windows swaps a bit more aggressively than you realize...but there is very little if any advantage to not having a swap file, other than using the free space for something else.

General advice is to keep at least a small (512MB or 1GB pagefile) as an insurance policy. I have successfully run workstations without a pagefile, but they were used for a specific purpose only and had plenty of headroom (extra RAM). Best practice for this guy's case (even if he has 4GB RAM) would be create a pagefile with min & max sizes equal to 512MB or 1GB.

Oh, and BTW, don't ever run DirectX games on a system without a pagefile....

I set 4 systems to run with no page file and let them run for 3 days while I was out of town. To make a long story short, every system experienced problems.

I have now set all 4 of these systems with a 500MB page file and set the local prefs to use 0.00% of the page file. My goal is to keep my WUs in RAM only.

I would like to get a few weeks of run time on these machines to see if this helps my RAC. These systems usually run in the 180 - 190 range so if I can get them over 200 I will be very pleased.

---

Thx!

Paul

I ran 5 systems with local prefs set to use 0.00% swap file. When I check the processes, the WUs look like they require about 250MB of RAM.

Does anyone know of a utility I can use to provide some visibility into the processes using the swap file?

I would like to verify that the WUs are 100% in RAM and using only RAM for all activities.

thx

---

Thx!

Paul

...........
Does anyone know of a utility I can use to provide some visibility into the processes using the swap file?

I would like to verify that the WUs are 100% in RAM and using only RAM for all activities.

thx

Hello Paul,
Process Explorer might be useful for you. Its freeware, originally from Sysinternals, it can now be found at: http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx

Success,
Path7.

The Process Explorer is EXACTLY what I needed. It looks like the WUs are still using some amount of virtual memory but they are kept mostly in RAM. I need to let this config run for a couple of weeks to see if it is better.

I will let you know and thank you for the help.

---

Thx!

Paul

Hi Paul,

The Process Explorer is EXACTLY what I needed.

Just right.

It looks like the WUs are still using some amount of virtual memory but they are kept mostly in RAM.

I'd like to quote you from your first post:

systems that have plenty of RAM to run XP without a swap file. I use these systems only for R@H and most of them are P4 with HT and 1.25GB of RAM.

1.25 GB on WinXP running two Rosettas is everything but a "plenty of RAM to run XP without a swap file". Keep in mind that Rosetta's processes often consume much more than 200-300 MB of memory. I've often seen it around 500 MB and my fattest ever noticed (not Ralph but) Rosetta WU peaked at 937.5 MB, check this Ralph thread.

I need to let this config run for a couple of weeks to see if it is better.

A hint: check TaskManager's or ProcessExplorer's Peak Commit Charge value (in the Sys Info window), it should be a bit or even better much lower than the amount of your installed RAM.

Peter

Thank you for the response.

I was working from the understanding that the WUs require about 400MB each. That would still leave over 400MB for WindowsXP to use for whatever it does.

These systems are dedicated crunchers that run almost nothing more the R@H. I have considered booting them to Linux with a USB drive or a CD and let them run that way b/c it sounds like Linux systems achieve about 20% more work. Even if it is only 5% or 10%, it is something. I just have not wanted to learn how to make it work.

Based on your comments, 2.5GB would be the smallest reliable memory model - right?

---

Thx!

Paul

This is my machine that doesn't have a swap file and never has any problems:

https://boinc.bakerlab.org/rosetta/results.php?hostid=587655

It's single-core so only 1 thread, but it runs Windows MCE (including watching & recording TV/playing Videos etc) and runs a copy of Rosetta. It's got 1.25GB RAM, although some of this is used for the onboard graphics.

HTH
Danny

---

I was working from the understanding that the WUs require about 400MB each. That would still leave over 400MB for WindowsXP to use for whatever it does.

These systems are dedicated crunchers that run almost nothing more the R@H. [...] Based on your comments, 2.5GB would be the smallest reliable memory model - right?

I would not go under safe 2GB for a dedicated XP rosetta cruncher. But once again: check the Peak Commit Charge value over long term. This is the amount of RAM your host needs.

Peter

I would not go under safe 2GB for a dedicated XP rosetta cruncher. But once again: check the Peak Commit Charge value over long term. This is the amount of RAM your host needs.

I wanted, but omitted to write: "I would not go under safe 2GB for a dedicated XP dual rosetta cruncher."

Peter