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Old 2021-08-23, 20:21   #287
gd_barnes
 
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Quote:
Originally Posted by rebirther View Post
R546 tested to n=2.5k + sieved to 1G (2.5-10k)

75963 remain

cant sieving higher than 715M

Results emailed - Base released
srsieve2 must not be working correctly. The file shows that it is sieved to P=715754497. Yet when I run srsieve on the file it is not removing factors at that sieve depth. This means that the file has already been sieved deeper than that.

I will attempt to sieve the file to P=1G using srsieve and see what point it starts removing factors.

I see that you have been having difficulty sieving to P=1G with srsieve2 for the last several large files with nearly 100,000 k's remaining. It might be time to consider srsieve again.
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Old 2021-08-23, 20:27   #288
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Quote:
Originally Posted by gd_barnes View Post
srsieve2 must not be working correctly. The file shows that it is sieved to P=715754497. Yet when I run srsieve on the file it is not removing factors at that sieve depth. This means that the file has already been sieved deeper than that.

I will attempt to sieve the file to P=1G using srsieve and see what point it starts removing factors.

I see that you have been having difficulty sieving to P=1G with srsieve2 for the last several large files with nearly 100,000 k's remaining. It might be time to consider srsieve again.
The first time it has stopped earlier. Tried 2 times with input file to resume from the last position with -W16 but running with the version from January, newer versions from srsieve2 has some issues.
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Old 2021-08-23, 20:54   #289
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Originally Posted by rebirther View Post
The first time it has stopped earlier. Tried 2 times with input file to resume from the last position with -W16 but running with the version from January, newer versions from srsieve2 has some issues.
I just now split the file over 4 cores running good old srsieve. It will finish sieving P=715M-1G in ~8-9 hours. I will let you know at what point it starts removing factors.

I get concerned about running buggy versions of software and using the files from those versions for future testing.

Edit: It has stopped early before. Both R358 and S330 stopped before P=1G earlier this year.

Last fiddled with by gd_barnes on 2021-08-23 at 21:17 Reason: edit
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Old 2021-08-24, 01:08   #290
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Reb, below are the 3 times that you could not sieve where you needed to with srsieve2 when there was a large number of k's remaining. One of these is your recent post about R546.

Quote:
Originally Posted by rebirther View Post
R358 tested to n=2.5k + sieved to 1G (2.5-10k)

265552 remain

sieved stopped at 964M because of 1 factor per 7000s+

Results emailed - Base released
Quote:
Originally Posted by rebirther View Post
S330 tested to n=2.5k + sieved to 1G (2.5-10k)

101096 remain

Results emailed - Base released

Sieving ended up at 32M after 2 runs with -t10 and -t16

Quote:
Originally Posted by rebirther View Post
R546 tested to n=2.5k + sieved to 1G (2.5-10k)

75963 remain

cant sieve higher than 715M

Results emailed - Base released
I did short multiple sieves on all of the files to see what their actual approximate sieve depth is. Here is what I found.

1. R358 is sieved to P=~964M like you stated in your post. But the file shows that it was sieved to P=694851893. Why is the file wrong? My sieves confirmed that P=~964M is correct. But the factor removal is faster than 1 per second. I don't know why you are showing one every 7000 secs.

2. S330 appears to be sieved to between P=300M and 350M somewhere. But you and the file show that it was sieved to P=32M. I'm getting ZERO factor removal at P=300M but many factors being removed per second at P=350M.

3. R546 appears to be sieved to P=1G. But you and the file show that it was sieved to P=715M. I'm getting no factor removal at various tests for P>715M including at P=990M. For additional verification I confirmed that factors were being removed at P>1G.

So I'm confused what is happening.

Below are my suggestions of what we should do. Please feel free to offer alternatives.

1. I can finish sieving R358 to P=1G.

2. For the S330 sieve depth, what you stated and what is in the file are very far off from the actual sieve depth. I feel like you should maybe start over the sieving of that one with a version of srsieve2 that you know is working properly.

3. As I stated above I will continue sieving R546 using srsieve for P=715M-1G to see if there are any missing factors. That effort will be complete in ~4 hours from this post. I do not expect to find any factors. If none are found I will simply update the sieve depth in the file.

I hope that future versions of srsieve2 are able to handle large numbers of k's remaining. Perhaps srsieve is better suited for such bases.

Last fiddled with by gd_barnes on 2021-08-24 at 01:12
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Old 2021-08-24, 05:22   #291
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Confirmed #3 in my last post: The file provided to me for R546 was already sieved to P=1G.
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Old 2021-08-24, 06:04   #292
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Quote:
Originally Posted by gd_barnes View Post
Confirmed #3 in my last post: The file provided to me for R546 was already sieved to P=1G.

There could be 2 issues why its not working. The amount of k's or the multicore option -W, in the past I ran without -W and it was working but its a mess with 30 folders and merging every file. I always running 16cores + 14HT
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Old 2021-08-24, 06:38   #293
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Quote:
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There could be 2 issues why its not working. The amount of k's or the multicore option -W, in the past I ran without -W and it was working but its a mess with 30 folders and merging every file. I always running 16cores + 14HT

That would be a mess!

I would like to do a comparison between srsieve and srsieve2: How many CPU hours did it take you to run that full sieve?

Here is what I did: I sieved P=715M-1G in ~8.5 hours on 4 cores. So that's ~34 CPU hours for a P=285M range. Extrapolating: If I sieved the entire range we'd have: 1000M total-range / 285M range that I sieved * 34 CPU hours = ~120 CPU hours. To be fair, add about ~10% since the higher P-ranges sieve faster. Therefore:

I estimate using srsieve it would have taken me ~135 CPU hours to sieve S548 for n=2.5K-10K to P=1G.

How does that compare to how much CPU time that it took you running srsieve2?

Last fiddled with by gd_barnes on 2021-08-24 at 06:39
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Old 2021-08-24, 07:01   #294
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Quote:
Originally Posted by gd_barnes View Post
That would be a mess!

I would like to do a comparison between srsieve and srsieve2: How many CPU hours did it take you to run that full sieve?

Here is what I did: I sieved P=715M-1G in ~8.5 hours on 4 cores. So that's ~34 CPU hours for a P=285M range. Extrapolating: If I sieved the entire range we'd have: 1000M total-range / 285M range that I sieved * 34 CPU hours = ~120 CPU hours. To be fair, add about ~10% since the higher P-ranges sieve faster. Therefore:

I estimate using srsieve it would have taken me ~135 CPU hours to sieve S548 for n=2.5K-10K to P=1G.

How does that compare to how much CPU time that it took you running srsieve2?
With -W16 around 20h if its working.
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Old 2021-08-24, 07:37   #295
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With -W16 around 20h if its working.
So...16 threads/cores * 20 hours = 320 CPU hours.

I estimated 135 CPU hours running srsieve with multiple instances. That's with an old (but very reliable) version of srsieve.

Consider the following when sieving in the future:

Split up the k's remaining into 8, 10, 12, or 16 pieces depending on the # of cores/threads you want to use. That's more efficient than splitting up P-ranges while running multiple cores on all k's. Sieve them all at the same time with separate instances of srsieve (or try it with srsieve2). Then use srfile to combine all of the files at the end. I'm pretty sure you'll save CPU time that way.

Of course that defeats the purpose of having a multi-threaded program, which is its ease of use. But if its using that much more CPU time then you might consider the extra personal time worth it.

My sieving machine is not real fast and not over-clocked. It's an AMD Ryzen 16 core/32 thread running at 3.2 Ghz.
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Old 2021-08-24, 08:46   #296
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Quote:
Originally Posted by gd_barnes View Post
So...16 threads/cores * 20 hours = 320 CPU hours.

I estimated 135 CPU hours running srsieve with multiple instances. That's with an old (but very reliable) version of srsieve.

Consider the following when sieving in the future:

Split up the k's remaining into 8, 10, 12, or 16 pieces depending on the # of cores/threads you want to use. That's more efficient than splitting up P-ranges while running multiple cores on all k's. Sieve them all at the same time with separate instances of srsieve (or try it with srsieve2). Then use srfile to combine all of the files at the end. I'm pretty sure you'll save CPU time that way.

Of course that defeats the purpose of having a multi-threaded program, which is its ease of use. But if its using that much more CPU time then you might consider the extra personal time worth it.

My sieving machine is not real fast and not over-clocked. It's an AMD Ryzen 16 core/32 thread running at 3.2 Ghz.
Mine is a 3950x but cant run 16core llr, too hot, reaching 95°C, with 16+14 the clockspeed is lower with 80°C and faster for the smaller tests
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Old 2021-08-24, 09:19   #297
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Mine is a 3950x but cant run 16core llr, too hot, reaching 95°C, with 16+14 the clock speed is lower with 80°C and faster for the smaller tests
That's too bad about the heat on your machine. Mine is also a 3950X. It isn't great for small and medium-length LLR testing but is an excellent siever and seems almost equal to my Intels on longer LLR tests.

The benchmark that I gave you for the 4 cores running srsieve was with 20 instances of LLR running at the same time. So 24 threads were in operation at that time. That is generally the most that I will run on it at one time.

Last fiddled with by gd_barnes on 2021-08-24 at 09:23
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