Illegal Sumout: MSN Windows Live ?!

[John S]

Hi I'm a noob so please be gentle! I joined this project just over a week ago. I've had Prime95 running about 12 hours a day since, with no errors. For info I'm running XP and have an AMD Sempron 2600+ (which I've figured out you'd want to know from reading the other threads...) However, my daughter occasionally uses this PC (even though she has a perfectly good one of her own) and of course uses MSN Windows Live (AKA Messenger). Since she upgraded MSN to v8.1 yesterday, I've noticed Prime95 has Illegal Sumout errors. It only seems to be when my daughter is using the PC, when MSN is running (which is kinda the same thing ;-) I just dry ran MSN in my account (we both use Limited Accounts for our day-to-day use) and sure enough, as soon as a message popped up (above the systray - it gives a little pop-up when you get a new message) an Illegal Sumout message appeared in the Prime95 window. So, I'm 98% certain that v8.1 of MSN Windows Live is conflicting with Prime95 somewhere along the line. And it seems to be when MSN produces one of those little pop-ups as described (I'm figuring others on this board will know what I'm talking about - I never use it myself). The error message also appeared in my daughter's account at exactly the same time that the pop-up came up. I appreciate this is more MSN's problem (like they'll care) than Prime95's but I thought I'd post anyway to see what others think. I'm probably going to uninstall MSN on this PC and re-install the previous version (daughter had been using that with no problems). But I was hoping to install Prime95 on my daughter's PC. I'm not going to force her to roll back her MSN though (unless it has other issues) so that idea will have to go on the backburner. Sorry for waffling, and I hope I've chosen the right forum to post this in. Any comments welcome!

[cheesehead]

Just a query to start: Have you read what the readme.txt file in your Prime95 subdirectory has to say about "ILLEGAL SUMOUT"?

Originally Posted by John S

I just dry ran MSN in my account (we both use Limited Accounts for our day-to-day use) and sure enough, as soon as a message popped up (above the systray - it gives a little pop-up when you get a new message) an Illegal Sumout message appeared in the Prime95 window.

This, along with your other observations (for which we thank you), may mean that when an MSN message pop-up occurs then ends, there is improper save/restore of the floating-point registers. (There are other possibilities, but this one has been reported to have been a flaw in other software elsewhere.) If that occurs, then in the middle of a Prime95 FFT calculation, one or more quantities may, suddenly and unexpectedly from the Prime95's lowest-priority point-of-view, change. At the end of the FFT transform (a fraction of a second later), a cross-check computation reveals a mismatch, which leads to the Illegal Sumout message.

I appreciate this is more MSN's problem (like they'll care) than Prime95's

(* sigh *) Yeah.

However, Prime95 is not powerless to protect itself in the face of the mighty MS monolith!!!

One thing you didn't tell us is whether after the Illegal Sumout messages, there are any other messages from Prime95, such as "Disregard last error" or something like that.

When Prime95 encounters Illegal Sumout or certain other problems, it goes back to the most recent save file (now you see why it makes one every half-hour!), restores the computation values from that file, then resumes calculation from that point. If it successfully gets past the point at which the Illegal Sumout occurred, then that was a "soft" error, not repeated when re-tried -- and Prime95 will usually post another message saying so. That later message may say "non-repeatable" (which is a Good Thing in this context). Do you see that on your system?

So Prime95 often recovers and continues to a successful completion, even in the too-easily-corruptible MS environs.

[John S]

Have you read what the readme.txt file in your Prime95 subdirectory has to say about "ILLEGAL SUMOUT"?

Yes, I did read that.

after the Illegal Sumout messages, are there any other messages from Prime95, such as "Disregard last error" or something like that.

This is an extract from the results.txt file: Iteration: 6470959/18248849, ERROR: ILLEGAL SUMOUT Possible hardware failure, consult the readme.txt file. Continuing from last save file. [Wed Apr 25 20:09:55 2007] Iteration: 6474883/18248849, ERROR: ILLEGAL SUMOUT Possible hardware failure, consult the readme.txt file. Continuing from last save file. [Wed Apr 25 21:14:55 2007] Iteration: 6507765/18248849, ERROR: ILLEGAL SUMOUT Possible hardware failure, consult the readme.txt file. Continuing from last save file. As you can see it doesn't seem to be the same iterations (which I guess is good?) These are the only sort of messages. I have reinstalled v8.0 of MSN although I haven't had a chance to dry run it (as I don't use the damn thing myself ;-) - I couldn't get it to give me one of those pop-ups (I think they're called "alerts"). I shall probably find out later today if it's been a problem (as my daughter will use the PC). I did notice, while ferreting round in the options, that you can turn the alerts off in MSN. So it could have been worth me trying that before uninstalling v8.1 - but I didn't notice until I had reinstalled v8.0. Cheers for the comments. And sorry about my double post :-\

[cheesehead]

Originally Posted by John S

Iteration: 6470959/18248849, ERROR: ILLEGAL SUMOUT Possible hardware failure, consult the readme.txt file. Continuing from last save file.
[Wed Apr 25 20:09:55 2007] Iteration: 6474883/18248849, ERROR: ILLEGAL SUMOUT Possible hardware failure, consult the readme.txt file. Continuing from last save file.
[Wed Apr 25 21:14:55 2007] Iteration: 6507765/18248849, ERROR: ILLEGAL SUMOUT Possible hardware failure, consult the readme.txt file. Continuing from last save file.

(1) Did each of these three messages occur immediately after an MSN alert?

(2a) Are there further SUMOUT messages beyond those? (2b) If so, does your iteration number (the xxxxxxx in xxxxxxx/18248849) keep getting higher each time?

If the answers to 1 and 2a are "yes, no" or answers to 1, 2a, and 2b are "yes, yes, yes", then I think your Prime95 is okay and your LL test result will be valid if there is no other type of error during the test.

As you can see it doesn't seem to be the same iterations (which I guess is good?)

As long as the iteration number increases each time, that's good.

These are the only sort of messages.

Just a doublecheck: Do you ever notice a SUMOUT message displayed at a time when an MSN alert has _not_ just occurred?

I have reinstalled v8.0 of MSN although I haven't had a chance to dry run it (as I don't use the damn thing myself ;-) - I couldn't get it to give me one of those pop-ups (I think they're called "alerts"). I shall probably find out later today if it's been a problem (as my daughter will use the PC). I did notice, while ferreting round in the options, that you can turn the alerts off in MSN. So it could have been worth me trying that before uninstalling v8.1 - but I didn't notice until I had reinstalled v8.0.

It will be helpful to us if you report:

(a) whether or not any SUMOUT messages occurring when MSN v8.0 is in use, and whether they occur just after an MSN alert or at some other time

(b) if you reinstall v8.1 and turn off alerts, are there any SUMOUT messages, and do you notice any common circumstances.

[John S]

(1) Did each of these three messages occur immediately after an MSN alert?

I think so, but as it's my daughter who uses it most of the time I can't be certain. But I come back to this below.

(2a) Are there further SUMOUT messages beyond those?

It is only happening with MSN. (As far as I can tell - there's been no problems at any other time. I did my usual malware scans the other day, which I guess are quite intensive (A2, Adaware, Spybot, Defender) and Prime95 happily ran in the background throughout.)

(2b) If so, does your iteration number (the xxxxxxx in xxxxxxx/18248849) keep getting higher each time?

Hmmm... don't think so. I've posted the extract from the results.txt file for today. I've deleted the following three lines from each entry. Apart from the times they're exactly the same. "Possible hardware failure, consult the readme.txt file. Continuing from last save file. [Fri Apr 27 21:31:35 2007]" Iteration: 8343524/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8330921/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329771/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8330125/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329540/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8331922/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8330070/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8331132/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8332213/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8330019/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8330658/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8330492/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8331690/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8333168/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8330547/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8330161/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329217/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329566/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329208/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329836/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8330144/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329281/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8331981/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329110/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329495/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329104/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329266/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329095/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329089/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329133/18248849, ERROR: ILLEGAL SUMOUT There doesn't seem to be any pattern to it. Other than it refers back to the last save file each time. My guess is that something is happening with MSN that trips Prime95 up, and it happens and different times after Prime95 starts again.

Just a doublecheck: Do you ever notice a SUMOUT message displayed at a time when an MSN alert has _not_ just occurred?

Definitely not when MSN hasn't been running. But see below.

It will be helpful to us if you report: (a) whether or not any SUMOUT messages occurring when MSN v8.0 is in use, and whether they occur just after an MSN alert or at some other time (b) if you reinstall v8.1 and turn off alerts, are there any SUMOUT messages, and do you notice any common circumstances.

OK, I disabled the alerts but these do not seem to be the culprit after all. I uninstalled 8.1 and reinstalled 8.0 - but this is also causing the problem. My daughter informs me that I had 7.5 installed on this machine before 8.1 - there are three other PCs in the flat. So I'm going to track down which machine has the 7.5 install file and reinstall that (good grief...) The only thing I can say is that when my daughter was on MSN earlier I had the Prime95 window open and watched very closely to see what happened when it next tripped up. She had three or four MSN windows open along the taskbar (I think these are separate conversations??) and as soon as one of the inactive ones flashed orange, Prime95 tripped up. But I only observed this once - I didn't continue watching as (apart from being a bit rude to my daughter!) I had just got home from work and wanted my dinner! I think the inactive windows on the taskbar flash orange when someone has just replied - I guess the window is trying to notify you of something. I just tried opening Excel, and going back to this (browser) window - when Excel finished loading the taskbar window flashed orange (as I expected) but am pleased to say this didn't trip up Prime95. I thought it might be worth a shot... I hope I've provided some useful information among all this. Thanks for looking at this. BTW - am I being stupid? Why don't my posts have any linebreaks? I'm using them, honest!

[cheesehead]

Everything you've added seems consistent with my previous opinion "your Prime95 is okay and your LL test result will be valid if there is no other type of error during the test".

Originally Posted by John S

I've deleted the following three lines from each entry. Apart from the times they're exactly the same. "Possible hardware failure, consult the readme.txt file. Continuing from last save file. [Fri Apr 27 21:31:35 2007]" Iteration: 8343524/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8330921/18248849, ERROR: ILLEGAL SUMOUT Iteration: 8329771/18248849,

< snip >

Thank you. I see by your iteration counts that you're not making progress between these MSN interruptions.

To alleviate that, change your "Minutes between disk writes:" to a small number of minutes -- try 10, or even 5 or less. Click on Prime95's "Options" then "Preferences" -- on that panel will be "Minutes between disk writes:".

The smaller time interval will give Prime95 a better chance of saving a block of valid progress before an error occurs, so it'll have less far to go back to resume each time. Each disk save will take only a few seconds.

There doesn't seem to be any pattern to it.

Actually, the pattern is that it's consistent with the theory that MSN is causing the trouble, especially because you don't observe it happening when MSN isn't running.

OK, I disabled the alerts but these do not seem to be the culprit after all.

Okay -- it may be that the problem occurs whenever MSN processes a certain type of message, even though alerts-off means it's not telling you about any of those messages. Thanks for trying.

I thought it might be worth a shot... I hope I've provided some useful information among all this.

Yes, you are! It seems conclusive (to me) that MSN software is causing the problem, and that the workaround is to use a short disk save time interval to minimize amount of calculation time lost on each occurrence.

Why don't my posts have any linebreaks?

With the software used in this forum, you need to either leave a blank line (press Enter twice), or use the

<br>

formatting command, which gives you a line break (two in a row

<br><br>

gives a blank line spacer).

When you press Enter only once, the forum software deletes that line break before displaying what you wrote.

[John S]

To alleviate that, change your "Minutes between disk writes:" to a small number of minutes -- try 10, or even 5 or less. Click on Prime95's "Options" then "Preferences" -- on that panel will be "Minutes between disk writes:".

Aha! That sounds like a plan. Although I think most of the time is taken up with poor old Prime95 waiting 5 minutes to try again. I've trained my daughter in how to turn it off (it clogs up the results file!) and turn it back on before logging off. I haven't got round to reinstalling v7.5 yet - as I'm sure that wasn't causing any problems. I have loads of install files for the various incarnations so I guess it's a case of deducting the right one from the modified dates :-\

I'll repost if I get round to reinstalling it to say what the results are.

Hopefully this will be useful for anyone else with the same problem.

HTML linebreaks it is then. Cheers for that :-)