How long has your system been running without a reset?
 

I was just curious what the longest period of time that anyones GIMPS computer out there has been running without a reset. Here at home, I don't think that I have ever exceeded 30 days due to the fact that I either install a new piece of software that requires a reset, or upgrade Windows with one of the numerous patches which also require a reset. I have also had one power failure. I can imagine that some of you out there have a system sitting off in a corner that you never touch that has been running MUCH longer.

I had a long (somewhat over 6 hour) power outage early this month.

At that point, several of my LINUX boxes had been running GIMPS 24/7 dedicated for 7-8 months - or since I first moved them over TO GIMPS from RC5/OGR.

My experience with GIMPS and distributed.net using LINUX dedicated cruncher boxes is that is the NORM - they keep running unless I get a hardware failure or a power outage too long for the UPSs to handle. It's one of the reasons I picked GIMPS as a change from RC5/OGR - the native client support for LINUX - and *one* of the reasons I geve up in disgust on United Devices - even though most of my boxes are NOT optimal for GIMPS work.

I have a P-II box in the corner of a lab at work that's been up for well over a year. The project for which it was purchased is long since completed, and at 300 MHz it's a bit of a wimp, so no one has any interest in touching it.

My PC at home needs to reboot at least once a week. It's mostly because I download anti-virus updates.

Too bad we can't run mprime on it...

Our forum server:

[code:1]%uptime
12:38PM up 145 days, 16:56, 2 users, load averages: 0.36, 0.52, 0.45[/code:1]

I think the longest continuously running client has been on one of my FreeBSD dual processor machines:

11:20AM up 146 days, 10:03, 1 user, load averages: 2.00, 2.00, 2.00

Currently, my NT4SP6a server has been up for 124 days; would have been longer but for the building repairing the electrical system. The same system was up for 229 days prior to that.

My Linux server was up over 170 days, but mprime wasn't running the whole time because mprime crashed for a few days when the primenet server went down. A power outage last Thursday destroyed my uptime.

Is a reset good for you?
 

I'd been running my P4 under Win2k for several weeks without any apparent problems and knocked off my first exponent. I then started on a 10,000,000 digit baby and had been crunching that for some days, generally getting an iteration time of 0.105 or 0.106 when I wondered if Linux might be faster. So I rebooted into Linux and miserably failed to get mprime installed (boy am I dumb when it comes to Linux! :rolleyes: ). But here's the interesting thing. When I rebooted into Win2k and ran Prime 95 again on the same exponent I was getting 0.097 to 0.098 iterations! And I had changed nothing in my setup.

Can a system reset actually improve times by freeing up some resources or other? or had I just frightened Windoze into trying harder in case I replaced it? :)

P.S. If anyone has the patience to explain to me how to get mprime working I'd appreciate it.

Well there could always be a process stealing cycles. The taskmanager is a good place to look. Add a column for cputime - cpu-usage should be on by default. Look for process having a large cpu-time after the machine has been up for a day or so.

Now to the linux stuff.

I will use the console to do all this.

How far have you got? First of all you need to make a directory where you want mprime to run - something like md /usr/local/mprime - then put the tar.gz archive there. (mv mprime.xxx.tar.gz /usr/local/mprime) - next we get to unpacking the archive, use tar xvfz mprime.xxx.tar.gz to do that - after that start it up with ./mprime -m - you have about the same menu as in windows, just that it is text-based. Set everything up and you are done.

Hth, Matthes

Re: Is a reset good for you?
 

[quote="kwstone"]Can a system reset actually improve times by freeing up some resources or other?[/quote]
My experience says this is quite possible. I run under Windows 2000 and I have seen this happen plenty of times. It is not always necessary even to go as far as a reboot: commonly just stopping Prime95 (Test > Stop) and then immediately restarting it has this effect. You might have to do this several times to achieve the best iteration time!

Using Task Manager I have established that there is no consistent drain on CPU time from other processes causing this effect, and I think there was an earlier discussion somewhere that tentatively led to a conclusion that the way system RAM (i.e. [i]not[/i] cache) was allocated led to this effect - if it was allocated more sequentially/contiguously or something like that the access was quicker. I am not personally sure if this is true (or even possible) but I have certainly demonstrated this phenomenon many times.

George: would you care to comment on this phenomenon?

Yes, if the memory allocated to Prime95 or mprime is contiguous and sequential, the accesses are smoother and the program runs a bit faster. A system restart/reload may allow memory to be more serially allocated to the first few programs that run.

On Windows systems, Brian Beesley's ReCache utility is designed to straighten out memory allocations.

Warning: ReCache makes two passes through memory. The second pass can be slow -- it may be faster to do a system reset than run ReCache.

[quote="Mersenne Digest Vol. 1 Number 652"]Date: Mon, 25 Oct 1999 19:23:14 +0100
From: "Brian J. Beesley" <bjb@bbhvig.u-net.com>
Subject: Re: Mersenne: ReCache for Windoze (was: mprime startup at boot-time)

On 24 Oct 99, at 18:23, Bruce A Metcalf wrote:

> Hello, I must have missed the discussion of ReCache the last time around.
> Would someone be willing to explain where this can be obtained, how to
> install, and the likely benefits to Prime95?

ftp://lettuce.edsc.ulst.ac.uk/gimps/software/ReCache.zip

To install: Unzip the file & place the executable in a directory referenced in the search path. [Or in the same directory as Prime95] Read the other file.

To run: from DOS command prompt: change directory to the folder containing Prime95 then issue the command "ReCache nn Prime95.exe" where nn is the amount of physical memory in the system in megabytes. Can easily be set up as a Windows shortcut.

Benefits: the ReCache program forces unused DLLs out to swap space & causes a general "tidy up" of the whole Windows memory space. This makes any compute-intensive program launched using it operate a little more efficiently. Speed up of 1% or 2% is usual.

> I'd also be particularly interested in an automatic routine, as my Windoze
> box crashes 3 or 4 times a day. (Yes, I know -- but I've only read through
> chapter 3 in "Linus for Dummies" so far.)

Place a shortcut to Prime95 (or to launch Prime95 using ReCache) in your startup folder, using "Start/Settings/Taskbar/Start Menu/Add"

But you probably should find out why windoze crashes so often. If you're on a busy LAN, it does help to have a full set of LAN security patches installed!

Regards
Brian Beesley
[/quote]

Home boxes usually suffer from power outage as the reason for going down. Current box has been up since late April (new build) and the rest of the crunchers for somewhat longer. Several work boxes had about 4000 hours in task manager. Unfortunately I did an office update which required a reboot.

Re: Is a reset good for you?
 

What mainboart are you using? I have a few that do that - cause is related to finishing P-1, but mine are on 98SE so I tend to blame that. Must migrate farm to w2kpro ...

Work boxes are all w2k on via chipset (AMD cpu) or intel chipset / willie cpu. Rebooting them has no effect on iteration times and these don't drift over the long haul.

[quote="kwstone"] When I rebooted into Win2k and ran Prime 95 again on the same exponent I was getting 0.097 to 0.098 iterations! And I had changed nothing in my setup.

Can a system reset actually improve times by freeing up some resources or other? or had I just frightened Windoze into trying harder in case I replaced it? :)

[/quote]

Heh, my web server runs mprime. 214 days uptime and counting.