Open miguelmarco opened 11 years ago
It would be good to provide more minimal code exhibiting the problem.
I'm setting the dependency simply because because any patch here might conflict with #14150.
Dependencies: #14150
Also, it seems you are running in the notebook. Does running it in the command-line make a difference?
Description changed:
---
+++
@@ -3,7 +3,7 @@
def trenza(f,points,exact=True,step=0.1,precision=53): if len(points)>2:
@parallel def siguehilo(f,x0,x1,y0a,d,Ak,R,F,RX,x,y,RY,dfx,dfy,exact,stepx):
I have trimmed down a little bit the code, but it is still very big.
I have tested on two different systems and the probabilities of hitting the problem seem to vary a lot. I have also experienced the same problem on the command line.
To trigger it i have to try several posibilities for the "exact" and "step" parameters. A combination that seems to work more often is this:
[trenza(f,[1,I,-1,-I,1],exact=True,step=0.5) for i in range(5)]
Each separated instance of
trenza(f,[1,I,-1,-I,1],exact=True,step=0.5)
takes around 3 seconds in my computer. But the list of five iterations doesn't give any answer even after several minutes.
If would be really good if you could simplify the code to better find out where it goes wrong.
Whats the expected output?
sage: [trenza(f,[1,I,-1,-I,1],exact=True,step=0.5) for i in range(5)]
[(None, (None, (None, None))),
(None, (None, (None, None))),
(None, (None, (None, None))),
(None, (None, (None, None))),
(None, (None, (None, None)))]
sage: trenza(f,[1,I,-1,-I,1],exact=True,step=0.5)
(None, (None, (None, None)))
Loop or no loop makes no difference here on Fedora 18 x86_64. Which OS are you on?
The expected is basically no output (the trenza function returns nothing, it is just to trigger the problem). As i said, the problem appears somehow randomly. Did you try to run it several times?
And as Murphy's law dictates, now the problem doesn't show in my system either ;)
I checked in both a Mageia server and my gentoo box. Both x86_64, with sage-5.7 compiled from source.
I get random freezes of a parallel process with the following code:
It is a code i am writing for computing braid monodromy of curves.
If i run it with, for example, this input:
I usually get the answer in a few seconds, but if i repeat several times the same computation, at some point it freezes, as if it was computing for a long time.
When i interrupt the computation i get the following traceback:
I really don't know how to catch the bug, and how to debug it.
Depends on #14150
Component: memleak
Keywords: parallel
Issue created by migration from https://trac.sagemath.org/ticket/14154