Pascal's OPN roadblock files

[wombatman]

This is what I was worried about. It got to ~40 million relations and I end up with this:

found 5162005 hash collisions in 40464281 relations
added 23 free relations
commencing duplicate removal, pass 2
found 4490571 duplicates and 35973733 unique relations
memory use: 197.2 MB
reading ideals above 720000
commencing singleton removal, initial pass
memory use: 1378.0 MB
reading all ideals from disk
memory use: 1282.0 MB
keeping 45221428 ideals with weight <= 200, target excess is 191371
commencing in-memory singleton removal
begin with 35973733 relations and 45221428 unique ideals
reduce to 4321 relations and 0 ideals in 17 passes

I assume I need to bump up the LPBA and add a sizable number of relations, yes?

[LaurV]

If you reduced them to ashes, then it might be over-sieved? Try again without some thousand lines, it may help. I remember I have seen a discussion about this in the past. It never happened to me, however, so I am not sure.

[chris2be8]

To judge by the last line:

 reduce to 4321 relations and 0 ideals in 17 passes

You need about 30% more relations.

Chris

[axn]

Originally Posted by wombatman

This is what I was worried about. It got to ~40 million relations and I end up with this

With a 29/30 combination, you'd need about 55M unique relations. Right now you have 35M. Add another 20-25M relations before retrying for a matrix. Keep adding 5M relations until you succeed.

[wombatman]

Thanks everybody. I'll report back with any new results.

[wombatman]

Hasn't completed yet, but it looks much better with more relations:

reduce to 13949767 relations and 14732971 ideals in 29 passes
max relations containing the same ideal: 96
filtering wants 1000000 more relations

Thanks for the help everybody.

[swellman]

This site has some good info on parameter selection.

There is a new thread the Math forum about estimating time to run GNFS that you might find interesting too.

Try out Yafu too.

[wombatman]

Thanks for pointing those out. A quick question on the Kamada graphs--for determining parameters, do you use the SNFS difficulty or the actual number of digits, at least for initial testing? Edit: Nevermind, I was being dumb. It looks like it goes with the difficulty, or at least Factmsieve does.

Also, the number I was working on ended up needing between 52M and 55M (I set minrels to 55M and it worked--at 52M, it needed more).

[wombatman]

Currently working on an SNFS 206. Now at over 65M relations (54.5M unique) and getting:

begin with 14655138 relations and 16282704 unique ideals
reduce to 13932177 relations and 15555212 ideals in 24 passes
max relations containing the same ideal: 184

Does this seem right?

[henryzz]

I assume that isn't the first pass of singleton removal. You are close but aren't quite there yet.

[wombatman]

Good deal. That was from the "in-memory singleton removal" step, so yes, I believe you're correct.