Opened 10 years ago
Closed 7 years ago
#11985 closed defect (fixed)
lcalc is too verbose (mysterious "Warning: new stack size")
Reported by:  was  Owned by:  jdemeyer 

Priority:  minor  Milestone:  sage6.2 
Component:  interfaces  Keywords:  lcalc 
Cc:  Merged in:  
Authors:  Jeroen Demeyer  Reviewers:  Travis Scrimshaw 
Report Upstream:  N/A  Work issues:  
Branch:  u/jdemeyer/ticket/11985 (Commits, GitHub, GitLab)  Commit:  f609cb0e20f8b23b95a7f1d9a74f0ab9ef37f899 
Dependencies:  #9640  Stopgaps: 
Description
I tried one simple example "by hand" that actually *uses* lcalc, and was not pleased by what happened:
sage: E = EllipticCurve('37a') sage: L = E.lseries() sage: L.zeros(10) *** Warning: new stack size = 1030944 (0.983 Mbytes). [0.000000000, 5.00317001, 6.87039122, 8.01433081, 9.93309835, 10.7751382, 11.7573247, 12.9583864, 15.6038579, 16.1920174] sage: L.zeros(10) *** Warning: new stack size = 1030944 (0.983 Mbytes). [0.000000000, 5.00317001, 6.87039122, 8.01433081, 9.93309835, 10.7751382, 11.7573247, 12.9583864, 15.6038579, 16.1920174]
Basically, every time you use lcalc to do anything with elliptic curve Lseries, you get some mysterious warning (of course, really output from PARI). However, the problem has been in released Sage for a long time. It was in sage4.7.
Change History (19)
comment:1 Changed 10 years ago by
 Dependencies set to #9640
comment:2 Changed 10 years ago by
 Component changed from elliptic curves to interfaces
 Owner changed from cremona to jdemeyer
comment:3 Changed 10 years ago by
 Milestone sage4.7.3 deleted
comment:4 Changed 7 years ago by
 Branch set to u/jdemeyer/ticket/11985
comment:5 Changed 7 years ago by
 Modified changed from 01/06/14 13:30:31 to 01/06/14 13:30:31
 Status changed from new to needs_review
comment:6 Changed 7 years ago by
 Commit set to d2ae836f3c5daea16049dbf02531be5429f90fbf
Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:
d2ae836  Use pari_init_stack() instead of old allocatemoremem()

comment:7 Changed 7 years ago by
 Commit changed from d2ae836f3c5daea16049dbf02531be5429f90fbf to f609cb0e20f8b23b95a7f1d9a74f0ab9ef37f899
Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:
f609cb0  Use pari_init_stack() instead of old allocatemoremem()

comment:8 Changed 7 years ago by
 Milestone set to sage6.1
comment:9 Changed 7 years ago by
 Keywords lcalc added
comment:10 Changed 7 years ago by
 Reviewers set to Travis Scrimshaw
 Status changed from needs_review to positive_review
Looks good to me.
comment:11 Changed 7 years ago by
 Resolution set to fixed
 Status changed from positive_review to closed
comment:12 Changed 7 years ago by
 Resolution fixed deleted
 Status changed from closed to new
I got this on mod during a doctests (somewhat random failure):
sage t long src/sage/schemes/elliptic_curves/lseries_ell.py ********************************************************************** File "src/sage/schemes/elliptic_curves/lseries_ell.py", line 243, in sage.schemes.elliptic_curves.lseries_ell.Lseries_ell.zeros Failed example: E.lseries().zeros(2) Expected: [0.000000000, 5.00317001] Got: *** Warning: not enough memory, new stack 1000000000. [0.000000000, 5.00317001] ********************************************************************** File "src/sage/schemes/elliptic_curves/lseries_ell.py", line 246, in sage.schemes.elliptic_curves.lseries_ell.Lseries_ell.zeros Failed example: a = E.lseries().zeros(20) # long time Expected nothing Got: *** Warning: not enough memory, new stack 1000000000. ********************************************************************** 1 item had failures:
This is also with #13163 but I'm pretty sure this ticket is the culprit...
comment:13 Changed 7 years ago by
 Status changed from new to needs_info
Please confirm that the system you were building this on was not low on memory. From reading the PARI sources, it looks like that message can only occur after a failed malloc()
. You should make sure doctests have 2.5GB of memory available.
comment:14 Changed 7 years ago by
 Status changed from needs_info to positive_review
comment:15 Changed 7 years ago by
As I said its on mod, so a pretty beefy machine with 128GB ram. Of course I don't know exactly what happened, but I think its pretty unlikely that some runaway process ate everything except 2% of the available ram such that only this doctest failed. Twice in a row.
comment:16 Changed 7 years ago by
Don't forget that mod
also runs the Sage Notebook server, which might make your scenario more likely. Were you testing many jobs in parallel? And were those the only doctest failures that you got?
comment:17 Changed 7 years ago by
That was the only failure in the whole build process and, at least when I checked later, there were tons (~50GB) of free memory. The buildbot always tests the same number of processes, no more, no less.
comment:18 Changed 7 years ago by
 Milestone changed from sage6.1 to sage6.2
comment:19 Changed 7 years ago by
 Resolution set to fixed
 Status changed from positive_review to closed
Milestone sage4.7.3 deleted