Stolen Assignment?
 

I was checking my assignment page earlier and noticed that one of my double-check assignments had vanished, even though it was yet to be completed. After a bit of investigation, I discovered that someone else had submitted a residue, even though I was still running it:

[URL]http://www.mersenne.org/report_exponent/?exp_lo=35327729&exp_hi=&full=1[/URL]

(I'm listed under J. Gareth Moreton) What's the deal with this? Granted, the machine in question is quite old (and hence slow), so I don't know if I was taking too long. The assignment only seemed to disappear when the new residue was submitted.

[QUOTE=CuriousKit;430267]I was checking my assignment page earlier and noticed that one of my double-check assignments had vanished, even though it was yet to be completed. After a bit of investigation, I discovered that someone else had submitted a residue, even though I was still running it:

[URL]http://www.mersenne.org/report_exponent/?exp_lo=35327729&exp_hi=&full=1[/URL]

(I'm listed under J. Gareth Moreton) What's the deal with this? Granted, the machine in question is quite old (and hence slow), so I don't know if I was taking too long. The assignment only seemed to disappear when the new residue was submitted.[/QUOTE]

Unfortunately, it looks like the machine was indeed a little too slow. The assignment in question would have been a Cat 1, which means that it must be completed within 60 days or else it is automatically recycled and reassigned to another user. You were assigned this exponent on 2016-02-02, so the expiration date of the assignment would have been 60 days later...but that is 2016-04-02. Now I am not sure why you were expired out on 2016-03-28; that would be worth having George and/or Aaron investigate. In any event, once the system expired your assignment, another user (mognuts) who likely had already run the test and had the result waiting, went ahead and submitted their result. Since that constituted a matching DC, your assignment was no longer needed, and hence was dropped from your workload.

It is, however, worth asking the question: Why was this assignment expired after only 55 days, rather than the 60 days that the assignment rules promise?

It is likely that this was a cat 1 DC due to expire in 60 days (so, another 4 days to go), and might not have been projected to complete in that time. (what was the ETA that P95 was showing?) They must've completed it and submitted it 4 days too early in their eagerness.

It could've also been a coordination issue in the "strategic doublecheck thread", where they were working on the TC of that exponent but failed to register the assignment with Primenet.

I think, if you let the assignment run its course, you would still get credit for it (not 100% sure on this one, though).

EDIT:- @NBtarheel_33, The expiry is an artefact of someone turning in a result. The cause and effect are the other way around, in this case.

[QUOTE=NBtarheel_33;430268]Why was this assignment expired after only 55 days, rather than the 60 days that the assignment rules promise?[/QUOTE]Because mognuts "poached" it.

I figured it was due to the machine's slow speed. The computer in question, codenamed "Shadow", is an old laptop with a broken screen that I'm effectively trying to run into the grave... hey, if I don't use it, I can at least make it useful!

Still a bit miffed that it expired before April 2nd though.

P.S. The estimated completion date is April 9th.

[QUOTE=axn;430269]
I think, if you let the assignment run its course, you would still get credit for it (not 100% sure on this one, though).[/QUOTE]

Extra LL/DC results do get credit. Duplicated TF results do not.

If I was only at 20% or so, I would have just cancelled it and started a new one, but since it is at 62.5% at the time of writing, I'll let it run its course and claim said credit, even though I seek to help find primes and clear the double-check backlog more than score points!

The machine in question I've configured to only do double-checks now due to its slow speed. Its other current assignment, an LL in the 79M range, is 100 days and counting... a little too long for my tastes! (I'm letting it finish though, just in case it's prime!)

[QUOTE=CuriousKit;430288]The machine in question I've configured to only do double-checks now due to its slow speed. Its other current assignment, an LL in the 79M range, is 100 days and counting... a little too long for my tastes! (I'm letting it finish though, just in case it's prime!)[/QUOTE]

What kind of CPU is it? If it is a multi-core, perhaps you can improve its useful life by using multi-threaded testing to speed up the tests.

It's an Intel Core 2 Duo running at 2.2 GHz (so 2 cores), although it's throttled to 90% due to overheating issues. But to give you an idea of how out of date it is, it doesn't have anything later than SSE2 in the instruction set, or it hasn't got SSE4.1 and SSE4.2 at least - I haven't checked for SSE3 and SSSE3 yet (no wonder it's so slow... no AVX opcodes or nice 256-bit YMM registers!)

A naïve question though... how does one set up multi-threading? It sounds like a much smarter idea.

[QUOTE=CuriousKit;430294]It's an Intel Core 2 Duo running at 2.2 GHz (so 2 cores), although it's throttled to 90% due to overheating issues. But to give you an idea of how out of date it is, it doesn't have anything later than SSE2 in the instruction set, or it hasn't got SSE4.1 and SSE4.2 at least - I haven't checked for SSE3 and SSSE3 yet (no wonder it's so slow... no AVX opcodes or nice 256-bit YMM registers!)

A naïve question though... how does one set up multi-threading? It sounds like a much smarter idea.[/QUOTE]
I am assuming that there is only one assignment and worker in worktodo.txt. In that case, pause P95, go to the Test menu in P95, and select Worker Windows..
In the last box, "CPUs to use (multithreading)", you should see the number '1'. Change that to '2'. When you restart processing, you should see a second Affinity line: "Setting affinity to run helper thread 1 on logical CPU #2."
You should monitor temperatures, as it will probably run hotter with 2 cores working. Blowing out the air passages of the laptop is a good idea, if you haven't recently.

Hope this helps.

At one point I had a large desk fan standing next to it to help cool it down, but found that throttling was a little more energy efficient (and quieter too).

It has two tasks running currently... the 79M exponent task that has been on my record for 100 days and is only at 38%, and the double-check test that is about to officially expire.

Most likely, I'll pause Prime95, manually modify the configuration file to put the two tasks under the same worker thread, then make the necessary modifications to the CPU usage. Thanks for the tips - I'll let you know how I do when I next get access to the machine later on.