mtsieve

[rogue]

Originally Posted by storm5510

I have an older package. With all due respect, I have not yet seen any good examples of how to use these things.

Sorry, but I have not updated the webpage in a while. Do you want to use a specific sieve from the framework?

[storm5510]

Originally Posted by rogue

Sorry, but I have not updated the webpage in a while. Do you want to use a specific sieve from the framework?

Not at this time. What web page are you referring to. Perhaps it might be of assistance, for learning.

[kruoli]

Here you go.

[rogue]

Originally Posted by kruoli

Here you go.

Horribly out of date. Working on an update.

[rogue]

Originally Posted by rogue

Horribly out of date. Working on an update.

Updated

[storm5510]

Originally Posted by kruoli

Here you go.

This is helpful. Many thanks!

Several years ago, when I was running LLR's, I used the srsieve group for several months. The command-line switches are different with this srsieve2. There were two min/max parameters then. I only see one now.

My RTX 2080 supports OpenCL, but using it did not seem to make much difference in throughput.

I will have to do more experimentation with this, and others.

[rogue]

Originally Posted by storm5510

This is helpful. Many thanks!

Several years ago, when I was running LLR's, I used the srsieve group for several months. The command-line switches are different with this srsieve2. There were two min/max parameters then. I only see one now.

My RTX 2080 supports OpenCL, but using it did not seem to make much difference in throughput.

I will have to do more experimentation with this, and others.

Yes, the command line parameters are different. This is part due to all sieves using some common parameters. Part of it is due to some of the parameters from srsieve have no equivalent in srsieve2 and srsieve2 have parameters that have no equivalent in srsieve.

srsieve2cl supports OpenCL. srsieve2 does not. srsieve2cl will start using the GPU when p > 1e6.

I have been using -g32 as that provides better rates compared to the default of -g8. With thousands of sequences you might need to use -K or -b with -K. You can also play around with -U, -V, and -X. You will likely need to use -M at lower p due to higher factor density. It will tell you if -M needs to be changed for the range.

Unfortunately the program does not "auto-tune" to come up with the best values for these parameters. I recommend that you find a fixed range that takes at least one minute to sieve then create a script to run that range multiple times, but changing the values for those switches. When done look at srsieve2.log to see which combination was the best.

[storm5510]

Originally Posted by rogue

Yes, the command line parameters are different. This is part due to all sieves using some common parameters. Part of it is due to some of the parameters from srsieve have no equivalent in srsieve2 and srsieve2 have parameters that have no equivalent in srsieve.

srsieve2cl supports OpenCL. srsieve2 does not. srsieve2cl will start using the GPU when p > 1e6.

I have been using -g32 as that provides better rates compared to the default of -g8. With thousands of sequences you might need to use -K or -b with -K. You can also play around with -U, -V, and -X. You will likely need to use -M at lower p due to higher factor density. It will tell you if -M needs to be changed for the range.

Unfortunately the program does not "auto-tune" to come up with the best values for these parameters. I recommend that you find a fixed range that takes at least one minute to sieve then create a script to run that range multiple times, but changing the values for those switches. When done look at srsieve2.log to see which combination was the best.

I found some of the older sieve programs on an external hard drive. sr1sieve, and others. I used the -h switch to look at the parameters for each. It seems my ability to remember things has dimmed somewhat. I can remember -p, -P, -n, and -N, but not much more. I used to run these from a batch file so I would not have to remember the specific switches. Looking through the forums might help.

[rogue]

Originally Posted by storm5510

I found some of the older sieve programs on an external hard drive. sr1sieve, and others. I used the -h switch to look at the parameters for each. It seems my ability to remember things has dimmed somewhat. I can remember -p, -P, -n, and -N, but not much more. I used to run these from a batch file so I would not have to remember the specific switches. Looking through the forums might help.

To start sieving one or more sequences with srsieve2/srsieve2cl the only required parameters are -s, -n, and -N. It will stop upon ^C if you do not specify -P. The output file name and format for that file are defaulted. You can change with -o and -F.

[rogue]

Here are some relative speeds for the programs. I used S750 from CRUS as the base for the sequences to be tested. I pre-sieved to 1e9. These times (in seconds) are for sieving from 1e9 to 2e9 with default values used for -g and -w. The CPU code ran on i9-11950H and the GPU code ran on NVIDIA RTX A5000.

          sr1sieve   sr2sieve   sr2sieve   srsieve2   srsieve2   srsieve2cl   srsieve2cl
                       w/Leg     wo/Leg      w/Leg     wo/Leg      w/Leg        wo/Leg
    1         54        n/a       n/a         65        218          30           30
   10        n/a        247       282        801        994         ***           91 
  100        n/a       1214      1580       3645       4198         ***          319

 *** -> uses generic sieving logic in the GPU, which does not support Legendre tables for multiple sequences

1000 sequences takes much longer, but I expect similar results. In other words srsieve2cl should be faster than anything else.

In the future I will add Legendre support in the GPU when using multiple sequences, but I'm not certain how much of a benefit it will have, especially when one has hundreds of sequences.

[storm5510]

Originally Posted by rogue

To start sieving one or more sequences with srsieve2/srsieve2cl the only required parameters are -s, -n, and -N. It will stop upon ^C if you do not specify -P. The output file name and format for that file are defaulted. You can change with -o and -F.

After doing more "digging" on my external drive, I found the batch files I had written for srsieve and sr1sieve. srsieve runs to a point then sr1sieve takes over after srfile does a conversion. This may take some time.

Many thanks!