#11900: Serious regression caused by #9138
-------------------------------------------------------------+--------------
Reporter: SimonKing | Owner:
tbd
Type: defect | Status:
positive_review
Priority: critical | Milestone:
sage-4.8
Component: performance | Keywords:
categories regression
Work_issues: Update reviewer patch | Upstream:
N/A
Reviewer: Jeroen Demeyer, Nicolas M. Thiéry, Simon King | Author:
Simon King
Merged: | Dependencies:
#9138 #11911 #9562
-------------------------------------------------------------+--------------
Old description:
> At [http://groups.google.com/group/sage-
> devel/browse_thread/thread/d885434ba9c22d66 sage-devel], Jeroen reported
> a massive regression in elliptic curve computations. The regression was
> introduced in the transition from sage-4.7.2.alpha2 to sage-4.7.2.alpha3.
>
> It seems that #9138 is responsible, at least for a big part of the
> regression. With unpatched sage-4.7.2.alpha2, we find
> {{{
> sage: E = J0(46).endomorphism_ring()
> sage: %time g = E.gens()
> CPU times: user 5.54 s, sys: 0.15 s, total: 5.69 s
> Wall time: 5.81 s
> }}}
> Adding #9138 and its dependency, we obtain
> {{{
> sage: E = J0(46).endomorphism_ring()
> sage: %time g = E.gens()
> CPU times: user 8.72 s, sys: 0.18 s, total: 8.89 s
> Wall time: 8.92 s
> }}}
>
> It turns out that much time is wasted for calls to
> `sage.categories.Category.join` and to
> `sage.categories.Category.hom_category`.
>
> When caching these two methods, one can reduce the speed difference to
> something like that (sage-4.7.2.alpha3 plus #11115 plus an experimental
> patch for the caching):
> {{{
> sage: E = J0(46).endomorphism_ring()
> sage: %time g = E.gens()
> CPU times: user 6.82 s, sys: 0.16 s, total: 6.98 s
> Wall time: 7.40 s
> }}}
> However, that's still far from good. After caching join and hom_category,
> there is still too much time spent (according to %prun) for the
> initialisation of matrix spaces.
>
> Apply [attachment:trac11900_category_speedup_combined.patch]
> or [attachment:trac11900_category_speedup_combined_Finitesingleton.patch]
> at your choice.
New description:
At [http://groups.google.com/group/sage-
devel/browse_thread/thread/d885434ba9c22d66 sage-devel], Jeroen reported a
massive regression in elliptic curve computations. The regression was
introduced in the transition from sage-4.7.2.alpha2 to sage-4.7.2.alpha3.
It seems that #9138 is responsible, at least for a big part of the
regression. With unpatched sage-4.7.2.alpha2, we find
{{{
sage: E = J0(46).endomorphism_ring()
sage: %time g = E.gens()
CPU times: user 5.54 s, sys: 0.15 s, total: 5.69 s
Wall time: 5.81 s
}}}
Adding #9138 and its dependency, we obtain
{{{
sage: E = J0(46).endomorphism_ring()
sage: %time g = E.gens()
CPU times: user 8.72 s, sys: 0.18 s, total: 8.89 s
Wall time: 8.92 s
}}}
It turns out that much time is wasted for calls to
`sage.categories.Category.join` and to
`sage.categories.Category.hom_category`.
When caching these two methods, one can reduce the speed difference to
something like that (sage-4.7.2.alpha3 plus #11115 plus an experimental
patch for the caching):
{{{
sage: E = J0(46).endomorphism_ring()
sage: %time g = E.gens()
CPU times: user 6.82 s, sys: 0.16 s, total: 6.98 s
Wall time: 7.40 s
}}}
However, that's still far from good. After caching join and hom_category,
there is still too much time spent (according to %prun) for the
initialisation of matrix spaces.
Apply [attachment:trac11900_category_speedup_combined.patch]
--
Comment(by jdemeyer):
I posted a comment at #11943: should I wait until #11943 also gets a
positive review in order to merge #9138, #11900 and #11943 together?
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/11900#comment:188>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/sage-trac?hl=en.
