add gc.collect() to the memleak test from #31313

[dimpase]

the memleak test added in #31313 does not use gc.collect(), which leads to random errors sometimes.

CC: @koffie @jhpalmieri @vbraun

Component: graph theory

Author: Dima Pasechnik

Branch: 872e9ad

Reviewer: John Palmieri

Issue created by migration from https://trac.sagemath.org/ticket/31671

[dimpase]

Author: Dima Pasechnik

[dimpase]

Branch: u/dimpase/graphs/add_gccollect_to_memleak_test

[dimpase]

New commits:

872e9ad

gc.collect() to normalise get_memory_usage() output

[dimpase]

Commit: 872e9ad

[dimpase]

comment:3

Please review!

[jhpalmieri]

comment:4

I still get the same occasional doctest failure:

sage [t/31671/graphs/add_gccollect_to_memleak_test] % ./sage -t src/sage/graphs/bipartite_graph.py
Running doctests with ID 2021-04-15-09-29-14-4df85c26.
Git branch: t/31671/graphs/add_gccollect_to_memleak_test
Using --optional=build,dochtml,homebrew,pip,sage,sage_spkg
Doctesting 1 file.
sage -t --warn-long 103.4 --random-seed=0 src/sage/graphs/bipartite_graph.py
**********************************************************************
File "src/sage/graphs/bipartite_graph.py", line 329, in sage.graphs.bipartite_graph.BipartiteGraph.__init__
Failed example:
    print(round(get_memory_usage() - start_mem))
Expected:
    0.0
Got:
    1.0
**********************************************************************
1 item had failures:
   1 of  14 in sage.graphs.bipartite_graph.BipartiteGraph.__init__
    [320 tests, 1 failure, 1.32 s]
----------------------------------------------------------------------
sage -t --warn-long 103.4 --random-seed=0 src/sage/graphs/bipartite_graph.py  # 1 doctest failed
----------------------------------------------------------------------
Total time for all tests: 1.4 seconds
    cpu time: 1.3 seconds
    cumulative wall time: 1.3 seconds

[dimpase]

comment:5

well, then there is a real platform-specific (macOS) bug.
Still, this patch makes sense to get in now and here.

[dimpase]

comment:6

or should we tag it as a # known bug ?

[jhpalmieri]

comment:7

I agree that the patch here can't hurt, and it could certainly help in some cases. We can merge this and separately can try to track down what's going on with OS X.

[jhpalmieri]

Reviewer: John Palmieri

[vbraun]

Changed branch from u/dimpase/graphs/add_gccollect_to_memleak_test to 872e9ad

[slel]

Changed commit from 872e9ad to none

[slel]

comment:9

Discussed again:

• sage-release (Sage 9.4.beta2 thread)

[dimpase]

comment:10

well, there is a bug in bipartite_graph, no way around it...