YAFU Version 2.11

[James Heinrich]

I just noticed this thread. Tried the latest v2.11 on my 7950X with a bunch of C79 from factordb.
It still has that same weird behaviour where it randomly crashes out in the middle of a factorization (e.g. during ECM or P-1).

[EdH]

I'm still having trouble with an occasional SIQS failure. To my untrained eye, it appears that YAFU is attempting to add relations, but they are not showing up:

starting SIQS on c70: 7193078225089295682426268467416399261468620513355262799015696435213249

==== sieving in progress ( 40 threads):   13104 relations needed ====
====             Press ctrl-c to abort and save state            ====
0 rels found: 0 full + 0 from 0 partial, (  0.00 rels/sec)
. . .
0 rels found: 0 full + 0 from 0 partial, (  0.00 rels/sec)
39 rels found: 39 full + 0 from 414 partial, (1738.93 rels/sec)
70 rels found: 69 full + 1 from 784 partial, (3182.50 rels/sec)
110 rels found: 107 full + 3 from 1169 partial, (4643.33 rels/sec)
. . .
13938 rels found: 6395 full + 7543 from 74638 partial, (71764.98 rels/sec)
13938 rels found: 6395 full + 7543 from 74638 partial, (71617.52 rels/sec)

building matrix with 13938 columns
Failed to find factors, re-trying with new relation target of 13759
rebuilding graph with 81033 buffered in-memory relations
13938 rels found: 6395 full + 7543 from 74638 partial, (33662.55 rels/sec)
13938 rels found: 6395 full + 7543 from 74638 partial, (33662.16 rels/sec)
. . .
13938 rels found: 6395 full + 7543 from 74638 partial, (33660.99 rels/sec)
13938 rels found: 6395 full + 7543 from 74638 partial, (33639.12 rels/sec)

building matrix with 13938 columns
Failed to find factors, re-trying with new relation target of 14446
rebuilding graph with 81033 buffered in-memory relations
13938 rels found: 6395 full + 7543 from 74638 partial, (22160.04 rels/sec)
13938 rels found: 6395 full + 7543 from 74638 partial, (22159.86 rels/sec)
. . .
13938 rels found: 6395 full + 7543 from 74638 partial, (22159.33 rels/sec)
13938 rels found: 6395 full + 7543 from 74638 partial, (22150.02 rels/sec)

building matrix with 13938 columns
Failed to find factors, re-trying with new relation target of 15168
rebuilding graph with 81033 buffered in-memory relations
13938 rels found: 6395 full + 7543 from 74638 partial, (16462.62 rels/sec)
13938 rels found: 6395 full + 7543 from 74638 partial, (16462.51 rels/sec)
. . .
13938 rels found: 6395 full + 7543 from 74638 partial, (16462.22 rels/sec)
13938 rels found: 6395 full + 7543 from 74638 partial, (16456.91 rels/sec)

building matrix with 13938 columns
Failed to find factors, re-trying with new relation target of 15926
rebuilding graph with 81033 buffered in-memory relations
13938 rels found: 6395 full + 7543 from 74638 partial, (13137.16 rels/sec)
13938 rels found: 6395 full + 7543 from 74638 partial, (13137.10 rels/sec)
. . .
13938 rels found: 6395 full + 7543 from 74638 partial, (13136.93 rels/sec)
13938 rels found: 6395 full + 7543 from 74638 partial, (13133.96 rels/sec)

building matrix with 13938 columns
Failed to find factors, re-trying with new relation target of 16722
rebuilding graph with 81033 buffered in-memory relations
SIQS elapsed time = 7.3945 seconds.


***factors found***


***co-factor***
C70 = 7193078225089295682426268467416399261468620513355262799015696435213249

ans = 7193078225089295682426268467416399261468620513355262799015696435213249

I've attached a couple full examples although they really only add the counting of each line of relations.

In case it's significant, I'm using inmem=100.

Thanks for all.

[Stargate38]

Both work on my end. I have inmem set to 75, but setting it to 100 doesn't change anything on my end:

C:\Numbers\yafu-master>yafu 7193078225089295682426268467416399261468620513355262799015696435213249
Applying tune_info entry for WIN64 - Intel(R) Core(TM) i5-9300H CPU @ 2.40GHz


YAFU Version 2.11
Built with Microsoft Visual Studio 1934 and Intel Compiler 2021
Using GMP-ECM 7.0.6-dev, Powered by MPIR 3.0.0
Detected Intel(R) Core(TM) i5-9300H CPU @ 2.40GHz
Detected L1 = 32768 bytes, L2 = 8388608 bytes, CL = 64 bytes
CPU features enabled: SSE41 AVX2 BMI2
Using 1 random witness for Rabin-Miller PRP checks
Cached 664579 primes; max prime is 9999991
Parsed yafu.ini from C:\Numbers\yafu-master

===============================================================
======= Welcome to YAFU (Yet Another Factoring Utility) =======
=======             bbuhrow@gmail.com                   =======
=======     Type help at any time, or quit to quit      =======
===============================================================

>> fac: factoring 7193078225089295682426268467416399261468620513355262799015696435213249
fac: using pretesting plan: deep
fac: using tune info for qs/gnfs crossover
input from file = 14289940376691307154546806758628389794060195806106065792881584318350516542239227
input to yafu = 7193078225089295682426268467416399261468620513355262799015696435213249
input from file = 3384479355371900826446280991735537190082644628099173553719008264462809917355371900826446280991735537190082644628099173553719
input to yafu = 7193078225089295682426268467416399261468620513355262799015696435213249
div: primes less than 10000
fmt: 1000000 iterations
93%fmt: performed 22 perfect square checks
rho: x^2 + 3, starting 4096 iterations on C70
rho: x^2 + 2, starting 4096 iterations on C70
rho: x^2 + 1, starting 4096 iterations on C70
pm1: starting B1 = 150K, B2 = gmp-ecm default on C70
pm1: Process took 0.1075 seconds.
fac: setting target pretesting digits to 23.333333
fac: estimated sum of completed work is t0.000000
fac: work done at B1=2000: 0 curves, max work = 30 curves
fac: 30 more curves at B1=2000 needed to get to t23.333333
ecm: 30/30 curves on C70, B1=2k, B2=gmp-ecm default
ecm: 23/30 curves on C70, B1=2k, B2=gmp-ecm default
fac: setting target pretesting digits to 23.333333
        t15: 1.00
        t20: 0.04
fac: estimated sum of completed work is t15.177725
fac: work done at B1=11000: 0 curves, max work = 74 curves
fac: 74 more curves at B1=11000 needed to get to t23.333333
ecm: 74/74 curves on C70, B1=11k, B2=gmp-ecm default
ecm: 61/74 curves on C70, B1=11k, B2=gmp-ecm default
ecm: 40/74 curves on C70, B1=11k, B2=gmp-ecm default
fac: setting target pretesting digits to 23.333333
        t15: 7.17
        t20: 1.04
        t25: 0.05
fac: estimated sum of completed work is t20.242996
fac: work done at B1=50000: 0 curves, max work = 214 curves
fac: 134 more curves at B1=50000 needed to get to t23.333333
ecm: 134/134 curves on C70, B1=50k, B2=gmp-ecm default, ETA: 0 sec 
ecm: 122/134 curves on C70, B1=50k, B2=gmp-ecm default, ETA: 1 sec
fac: setting target pretesting digits to 23.333333
        t15: 26.31
        t20: 7.42
        t25: 0.67
        t30: 0.04
fac: estimated sum of completed work is t23.373837
fac: QS time estimation from tune data = 2.11 sec
fac: GNFS time estimation from tune data = 272.81 sec
fac: tune params predict 2.11 sec for SIQS and 272.81 sec for NFS
fac: tune params scheduling SIQS work

starting SIQS on c70: 7193078225089295682426268467416399261468620513355262799015696435213249
input from file = 14289940376691307154546806758628389794060195806106065792881584318350516542239227
input to yafu = 7193078225089295682426268467416399261468620513355262799015696435213249
assigning tdiv_medprimes_32k_avx2 ptr
assigning tdiv_LP_avx2 ptr
assigning resieve_medprimes_32k_avx2 ptr
assigning med_sieveblock_32k_avx2 ptr
assigning nextRoots_32k_avx2_intrin ptr
fb bounds
        small: 1024
        SPV: 27
        10bit: 88
        11bit: 160
        12bit: 280
        13bit: 528
        32k div 3: 672
        14bit: 960
        15bit: 1760
        med: 2896
        large: 7456
        large_x2: 13040
        all: 13040
start primes
        SPV: 241
        10bit: 1123
        11bit: 2111
        12bit: 4127
        13bit: 8293
        32k div 3: 11047
        14bit: 16553
        15bit: 33049
        med: 57527
        large: 163673
        large_x2: 302587
        all: 302587

==== sieve params ====
n = 70 digits, 233 bits
factor base: 13040 primes (max prime = 302587)
single large prime cutoff: 25719895 (85 * pmax)
double large prime range from 91558892569 to 9289045383747
DLP MFB = 1.75
allocating 4 large prime slices of factor base
buckets hold 2048 elements
large prime hashtables have 327680 bytes
using AVX2 enabled 32k sieve core
sieve interval: 5 blocks of size 32768
polynomial A has ~ 9 factors
using multiplier of 1
using Q2(x) polynomials for kN mod 8 = 1
using in-memory storage, aborts will lose all progress
using SPV correction of 20 bits, starting at offset 27
trial factoring cutoff at 75 bits

==== sieving in progress (  8 threads):   13104 relations needed ====
====             Press ctrl-c to abort and save state            ====
13673 rels found: 5686 full + 7987 from 89526 partial, (30842.97 rels/sec)

sieving required 26162 total polynomials (206 'A' polynomials)
trial division touched 1123783 sieve locations out of 8572764160
dlp-ecm: 0 failures, 30208 attempts, 309273 outside range, 198574 prp, 29772 useful
total reports = 1123783, total surviving reports = 603495
total blocks sieved = 261620, avg surviving reports per block = 2.31
Elapsed time: 3.0870 sec
QS elapsed time = 3.0900 seconds.

==== post processing stage (msieve-1.38) ====
read 95212 relations
begin singleton removal with 95212 relations
reduce to 23550 relations in 7 passes
attempting to read and process 23550 relations
recovered 23550 relations
recovered 15511 polynomials
attempting to build 13673 cycles
found 13673 cycles from 23550 relations in 3 passes
distribution of cycle lengths:
   length 1 : 5686
   length 2 : 4919
   length 3 : 2013
   length 4 : 699
   length 5 : 248
   length 6 : 85
   length 7 : 16
   length 9+: 7
largest cycle: 9 relations
building matrix with 13673 columns
matrix is 13040 x 13673 (2.1 MB) with weight 443333 (32.42/col)
sparse part has weight 443333 (32.42/col)
filtering completed in 4 passes
matrix is 11898 x 11962 (1.7 MB) with weight 356288 (29.78/col)
sparse part has weight 356288 (29.78/col)
saving the first 48 matrix rows for later
matrix is 11850 x 11962 (1.4 MB) with weight 285190 (23.84/col)
sparse part has weight 249192 (20.83/col)
matrix includes 64 packed rows
commencing Lanczos iteration
memory use: 1.9 MB
lanczos halted after 189 iterations (dim = 11844)
recovered 13 nontrivial dependencies
Lanczos elapsed time = 2.1720 seconds.
Sqrt elapsed time = 0.0200 seconds.
SIQS elapsed time = 5.2822 seconds.
pretesting / qs ratio was 2.41
Total factoring time = 18.4442 seconds


***factors found***

P38 = 36778125298740129629221829539366277381
P33 = 195580339309347601712283486553229

ans = 1


C:\Numbers\yafu-master>yafu 8904029861692348898844855788190213555881777216202881511828039505900141
Applying tune_info entry for WIN64 - Intel(R) Core(TM) i5-9300H CPU @ 2.40GHz


YAFU Version 2.11
Built with Microsoft Visual Studio 1934 and Intel Compiler 2021
Using GMP-ECM 7.0.6-dev, Powered by MPIR 3.0.0
Detected Intel(R) Core(TM) i5-9300H CPU @ 2.40GHz
Detected L1 = 32768 bytes, L2 = 8388608 bytes, CL = 64 bytes
CPU features enabled: SSE41 AVX2 BMI2
Using 1 random witness for Rabin-Miller PRP checks
Cached 664579 primes; max prime is 9999991
Parsed yafu.ini from C:\Numbers\yafu-master

===============================================================
======= Welcome to YAFU (Yet Another Factoring Utility) =======
=======             bbuhrow@gmail.com                   =======
=======     Type help at any time, or quit to quit      =======
===============================================================

>> fac: factoring 8904029861692348898844855788190213555881777216202881511828039505900141
fac: using pretesting plan: deep
fac: using tune info for qs/gnfs crossover
input from file = 14289940376691307154546806758628389794060195806106065792881584318350516542239227
input to yafu = 8904029861692348898844855788190213555881777216202881511828039505900141
input from file = 3384479355371900826446280991735537190082644628099173553719008264462809917355371900826446280991735537190082644628099173553719
input to yafu = 8904029861692348898844855788190213555881777216202881511828039505900141
div: primes less than 10000
fmt: 1000000 iterations
99%fmt: performed 23 perfect square checks
rho: x^2 + 3, starting 4096 iterations on C70
rho: x^2 + 2, starting 4096 iterations on C70
rho: x^2 + 1, starting 4096 iterations on C70
pm1: starting B1 = 150K, B2 = gmp-ecm default on C70
pm1: Process took 0.0990 seconds.
fac: setting target pretesting digits to 23.333333
fac: estimated sum of completed work is t0.000000
fac: work done at B1=2000: 0 curves, max work = 30 curves
fac: 30 more curves at B1=2000 needed to get to t23.333333
ecm: 30/30 curves on C70, B1=2k, B2=gmp-ecm default
ecm: 15/30 curves on C70, B1=2k, B2=gmp-ecm defaultcm: 10/30 curves on C70, B1=2k, B2=gmp-ecm default
fac: setting target pretesting digits to 23.333333
        t15: 1.00
        t20: 0.04
fac: estimated sum of completed work is t15.177725
fac: work done at B1=11000: 0 curves, max work = 74 curves
fac: 74 more curves at B1=11000 needed to get to t23.333333
ecm: 74/74 curves on C70, B1=11k, B2=gmp-ecm default
ecm: 68/74 curves on C70, B1=11k, B2=gmp-ecm default
ecm: 35/74 curves on C70, B1=11k, B2=gmp-ecm default
fac: setting target pretesting digits to 23.333333
        t15: 7.17
        t20: 1.04
        t25: 0.05
fac: estimated sum of completed work is t20.242996
fac: work done at B1=50000: 0 curves, max work = 214 curves
fac: 134 more curves at B1=50000 needed to get to t23.333333
ecm: 134/134 curves on C70, B1=50k, B2=gmp-ecm default, ETA: 0 sec 
ecm: 128/134 curves on C70, B1=50k, B2=gmp-ecm default, ETA: 0 sec
fac: setting target pretesting digits to 23.333333
        t15: 26.31
        t20: 7.42
        t25: 0.67
        t30: 0.04
fac: estimated sum of completed work is t23.373837
fac: QS time estimation from tune data = 2.11 sec
fac: GNFS time estimation from tune data = 272.81 sec
fac: tune params predict 2.11 sec for SIQS and 272.81 sec for NFS
fac: tune params scheduling SIQS work

starting SIQS on c70: 8904029861692348898844855788190213555881777216202881511828039505900141
input from file = 14289940376691307154546806758628389794060195806106065792881584318350516542239227
input to yafu = 8904029861692348898844855788190213555881777216202881511828039505900141
assigning tdiv_medprimes_32k_avx2 ptr
assigning tdiv_LP_avx2 ptr
assigning resieve_medprimes_32k_avx2 ptr
assigning med_sieveblock_32k_avx2 ptr
assigning nextRoots_32k_avx2_intrin ptr
fb bounds
        small: 1024
        SPV: 30
        10bit: 88
        11bit: 144
        12bit: 280
        13bit: 488
        32k div 3: 640
        14bit: 920
        15bit: 1760
        med: 2896
        large: 7440
        large_x2: 13040
        all: 13040
start primes
        SPV: 233
        10bit: 1163
        11bit: 2053
        12bit: 4091
        13bit: 8243
        32k div 3: 10987
        14bit: 16447
        15bit: 33247
        med: 57637
        large: 163613
        large_x2: 304039
        all: 304039

==== sieve params ====
n = 70 digits, 233 bits
factor base: 13040 primes (max prime = 304039)
single large prime cutoff: 25843315 (85 * pmax)
double large prime range from 92439713521 to 9367191243882
DLP MFB = 1.75
allocating 4 large prime slices of factor base
buckets hold 2048 elements
large prime hashtables have 327680 bytes
using AVX2 enabled 32k sieve core
sieve interval: 5 blocks of size 32768
polynomial A has ~ 9 factors
using multiplier of 1 (kn mod 8 == 5)
using in-memory storage, aborts will lose all progress
using SPV correction of 21 bits, starting at offset 30
trial factoring cutoff at 75 bits

==== sieving in progress (  8 threads):   13104 relations needed ====
====             Press ctrl-c to abort and save state            ====
13580 rels found: 5226 full + 8354 from 97865 partial, (27341.61 rels/sec)

sieving required 33655 total polynomials (265 'A' polynomials)
trial division touched 1466187 sieve locations out of 11028070400
dlp-ecm: 0 failures, 40848 attempts, 347906 outside range, 251687 prp, 40394 useful
total reports = 1466187, total surviving reports = 703138
total blocks sieved = 336550, avg surviving reports per block = 2.09
Elapsed time: 3.7705 sec
QS elapsed time = 3.7745 seconds.

==== post processing stage (msieve-1.38) ====
read 103091 relations
begin singleton removal with 103091 relations
reduce to 24837 relations in 7 passes
attempting to read and process 24837 relations
recovered 24837 relations
recovered 17547 polynomials
attempting to build 13580 cycles
found 13580 cycles from 24837 relations in 3 passes
distribution of cycle lengths:
   length 1 : 5226
   length 2 : 4508
   length 3 : 2270
   length 4 : 966
   length 5 : 394
   length 6 : 146
   length 7 : 48
   length 9+: 22
largest cycle: 10 relations
building matrix with 13580 columns
matrix is 13040 x 13580 (2.2 MB) with weight 469115 (34.54/col)
sparse part has weight 469115 (34.54/col)
filtering completed in 4 passes
matrix is 12179 x 12243 (1.9 MB) with weight 392558 (32.06/col)
sparse part has weight 392558 (32.06/col)
saving the first 48 matrix rows for later
matrix is 12131 x 12243 (1.5 MB) with weight 320104 (26.15/col)
sparse part has weight 282445 (23.07/col)
matrix includes 64 packed rows
commencing Lanczos iteration
memory use: 2.0 MB
lanczos halted after 193 iterations (dim = 12128)
recovered 14 nontrivial dependencies
Lanczos elapsed time = 2.4580 seconds.
Sqrt elapsed time = 0.0220 seconds.
SIQS elapsed time = 6.2544 seconds.
pretesting / qs ratio was 1.93
Total factoring time = 18.7810 seconds


***factors found***

P31 = 9902998934502241704533809840921
P39 = 899124590498594820097612439217556424821

ans = 1

[bsquared]

EdH's problem is intermittent. Sometimes post processing will start too early when lots of cores are used and sometimes all dependencies will produce a trivial factorization. In both cases the solution is to sieve more and try again. I put in code to do that, and I thought it worked, but I guess I was wrong. I haven't had much time for another try at it, but I'll get to it at some point.

[birtwistlecaleb]

i found out that the gc version works well.

(context: this post was about a similar siqs issue)

[BudgieJane]

TL;DR = delete sigs.dat before running yafu on a particular number for the first time.


I've had that problem as well. If you remember, I usually call YAFU automatically from my application, and it's this that goes wrong occasionally. However, after this happened today, I called YAFU manually from its own directory, and it worked. Here are some diagnostics: first of all the automatic call from my application (just the SIQS bit)

05/08/23 14:38:53, starting SIQS on c89: 35761714489199661945209000116376720917040498268122704288680763161443979238900836003352289
05/08/23 14:38:53, random seed: 110715191753848095
05/08/23 14:38:53, ==== sieve params ====
05/08/23 14:38:53, n = 89 digits, 295 bits
05/08/23 14:38:53, factor base: 69824 primes (max prime = 1856297)
05/08/23 14:38:53, single large prime cutoff: 204192670 (110 * pmax)
05/08/23 14:38:53, double large prime range from 3445838552209 to 2363601591436203
05/08/23 14:38:53, DLP MFB = 1.85
05/08/23 14:38:53, using AVX512BW enabled 32k sieve core
05/08/23 14:38:53, sieve interval: 8 blocks of size 32768
05/08/23 14:38:53, polynomial A has ~ 11 factors
05/08/23 14:38:53, using multiplier of 1
05/08/23 14:38:53, using multiplier of 1
05/08/23 14:38:53, using Q2(x) polynomials for kN mod 8 = 1
05/08/23 14:38:53, using SPV correction of 19 bits, starting at offset 35
05/08/23 14:38:53, trial factoring cutoff at 92 bits
05/08/23 14:38:53, ==== sieving started ( 4 threads) ====
05/08/23 14:38:53, trial division touched 0 sieve locations out of 0
05/08/23 14:38:53, total reports = 0, total surviving reports = 0
05/08/23 14:38:53, total blocks sieved = 0, avg surviving reports per block = -nan(ind)
05/08/23 14:38:53, dlp-ecm: 0 failures, 0 attempts, 0 outside range, 0 prp, 0 useful
05/08/23 14:38:53, 70301 relations found: 22085 full + 48216 from 878220 partial, using 0 polys (0 A polys)
05/08/23 14:38:53, on average, sieving found inf rels/poly and 2047879.12 rels/sec
05/08/23 14:38:53, trial division touched 0 sieve locations out of 0
05/08/23 14:38:53, ==== post processing stage (msieve-1.38) ====

and there it exits and returns to my application.

Now the manual version

starting SIQS on c89: 35761714489199661945209000116376720917040498268122704288680763161443979238900836003352289

==== sieving in progress (  4 threads):   69888 relations needed ====
====             Press ctrl-c to abort and save state            ====
70390 rels found: 22237 full + 48153 from 902659 partial, (7594.84 rels/sec)

building matrix with 70390 columns
SIQS elapsed time = 131.1278 seconds.
Total factoring time = 188.8053 seconds


***factors found***

P56 = 15462823480129404505066388742085588299840884826588594913
P34 = 2312754493715554016956912992996353

ans = 1

When I looked at that I realized I forgot to add the verbose flags to the YAFU call, so I tried to run the manual version again with -v -v -v. Imagine my surprise when it didn't work (i.e. it didn't produce the factors). I looked through the output on the screen, and I noticed that the preliminaries didn't go through the ecm stuff again, even though I had not specifiied -R on the command and it is not in yafu.ini. So this implies to me that something that changed the first time I ran it affects subsequent runs as though -R were specified, and that must be the previous savefile (from the documentation). So I had a look at the files in the directory that I called yafu from, and I saw the file siqs.dat which had the date and time of the latest run, so I immediately thought "what happens if I delete that?" So I deleted it and ran the manual version again, and it worked.

So I went to the directory that yafu gets called from in my application, and deleted siqs.dat from there, and then repeated my run from my application. And, thank heavens, it worked. So it seems that the fix for my problem is to delete siqs.dat before running yafu, which shouldn't be a problem as I'm not going to try to run yafu on the same number more than once ordinarily. It may not stop the problem reoccuring, but I hope it does.

I don't know if this will affect other people's problems, but I put it forward as something to look at.

I have a couple of questions:
- Is siqs.dat the name of the previous savefile, or am I barking up the wrong tree?
- What does yafu do differently depending on the presence or absence of siqs.dat?


Sorry this is so long.

[James Heinrich]

Would it be possible to have an option to output only JSON to stdout?

Right now I can call ./yafu '123456789' and get the factoring progress followed by:

***factors found***

P13 = 1154905652933
P68 = 10770501407167744869020364926833770037404552145874242009905692194033

ans = 1

If I add -silent it's too silent, just outputs 1.

Would it be possible to have an option like -jsonscreen where it would just print the JSON result line to stdout?
{ "input-expression":"factor(123456789)", "input-decimal":"123456789", "input-argument-string":"123456789 ", "factors-prime":["3","3","3607","3803"], "runtime" : {"total":0.0002}, "time-start" : "2023-05-09 10:34:21", "time-end" : "2023-05-09 10:34:21", "info":{"compiler":"GNUC 11","ECM-version":"7.0.6-dev","GMP-version":"6.2.1","yafu-version":"2.10"} }

This can be pulled from factor.json of course, but it would be easier just to grab it from stdout.

[Denial140]

When running 40332148362698186503207202016403392614370799382249149846314221161361155086431334693701404827921704387044 in yafu 2.11 with -pretune, it consistently reaches an infinite loop on C27=199063039811021252248642153. It looks like the issue is caused by finding an ECM factor, and a trivial amount of ECM for the remaining composite, triggering line 1237 of factor/autofactor.c.

Apologies if this is known or not the right place to report this kind of thing.

[Stargate38]

What does "Error: M=10^28" mean, and what's the workaround to getting SNFS to work? I was trying to factor the C106 from 10^109*409522002-53310761, and I got the following output:

Applying tune_info entry for WIN64 - Intel(R) Core(TM) i5-9300H CPU @ 2.40GHz


YAFU Version 2.11
Built with Microsoft Visual Studio 1934 and Intel Compiler 2021
Using GMP-ECM 7.0.6-dev, Powered by MPIR 3.0.0
Detected Intel(R) Core(TM) i5-9300H CPU @ 2.40GHz
Detected L1 = 32768 bytes, L2 = 8388608 bytes, CL = 64 bytes
CPU features enabled: SSE41 AVX2 BMI2
Using 1 random witness for Rabin-Miller PRP checks
Cached 664579 primes; max prime is 9999991
Parsed yafu.ini from C:\Numbers\yafu-master

===============================================================
======= Welcome to YAFU (Yet Another Factoring Utility) =======
=======             bbuhrow@gmail.com                   =======
=======     Type help at any time, or quit to quit      =======
===============================================================

>> nfs: checking for job file - job file found, testing for matching input
input from file = 4622287850254535685448462647685575025651986357826695554551610526005995631281348164595285069118676184303
input to yafu = 4095220019999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999946689239
nfs: number in job file does not match input
nfs: checking for poly file - no poly file found
nfs: commencing nfs on c118: 4095220019999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999946689239
nfs: searching for brent special forms...
nfs: checking a*b^x +/- c for 32 <= x <= 1478
nfs: checking a*b^x +/- c for 32 <= x <= 933
nfs: checking a*b^x +/- c for 32 <= x <= 637
nfs: checking a*b^x +/- c for 32 <= x <= 572
nfs: checking a*b^x +/- c for 32 <= x <= 527
nfs: checking a*b^x +/- c for 32 <= x <= 445
nfs: input divides 409522002*10^109 - 53310761
nfs: snfs form detection took 0.002994 seconds
gen: ========================================================
gen: considering the following polynomials:
gen: ========================================================

nfs: checking degree 4 poly
Error: M=10000000000000000000000000000

Event Viewer:

Faulting application name: yafu.exe, version: 0.0.0.0, time stamp: 0x64337825
Faulting module name: ucrtbase.dll, version: 10.0.19041.789, time stamp: 0x2bd748bf
Exception code: 0xc0000409
Fault offset: 0x0000000000071208
Faulting process id: 0x2208
Faulting application start time: 0x01d98beebcb82948
Faulting application path: C:\Numbers\yafu-master\yafu.exe
Faulting module path: C:\WINDOWS\System32\ucrtbase.dll
Report Id: fdb2b54c-4b7c-42be-9037-9a51ee4c23bf
Faulting package full name: 
Faulting package-relative application ID: