Slow operation with some PDFs #87
Description
(FIXME: update this issue from email correspondence about it.)
Seems like a lot of time is spent in _page.py's _merge_resources method, and of that, a lot is spent in typing's __instancecheck__.
pstops -pletter 16:0(0.50w,0.00h)+15(0.00w,0.00h)+3U(1.00w,1.00h)+12U(0.50w,1.00h),1(0.0w,0.00h)+14(0.50w,0.00h)+2U(0.5w,1.00h)+13U(1.00w,1.00h),4(0.50w,0.0h)+11(0.0w,0.0h)+7U(1.00w,1.00h)+8U(0.50w,1.00h),5(0.0w,0.0h)+10(0.50w,0.0h)+9U(1.00w,1.00h)+6U(0.50w,1.00h) 2026_weekbook_trial_002.pdf 2026_weekbook_trial_002_pstops.pdf
^C 21299954039 function calls (21299827432 primitive calls) in 3278.968 seconds
Ordered by: cumulative time
ncalls tottime percall cumtime percall filename:lineno(function)
179/1 0.003 0.000 3278.969 3278.969 {built-in method builtins.exec}
1 0.000 0.000 3278.969 3278.969 <string>:1(<module>)
1 0.000 0.000 3278.969 3278.969 <frozen runpy>:201(run_module)
1 0.000 0.000 3278.905 3278.905 <frozen runpy>:65(_run_code)
1 0.000 0.000 3278.905 3278.905 pstops.py:1(<module>)
1 0.000 0.000 3278.905 3278.905 pstops.py:104(pstops)
1 0.000 0.000 3278.791 3278.791 transformers.py:65(transform_pages)
1 0.000 0.000 3278.791 3278.791 transformers.py:85(transform_pages)
29 0.001 0.000 3278.790 113.062 transformers.py:408(write_page)
115 0.000 0.000 3278.782 28.511 _page.py:1362(merge_transformed_page)
115 0.003 0.000 3278.782 28.511 _page.py:1069(_merge_page)
115 0.021 0.000 3278.779 28.511 _page.py:1183(_merge_page_writer)
343 348.757 1.017 3277.685 9.556 _page.py:832(_merge_resources)
1934603605 508.871 0.000 2872.005 0.000 _data_structures.py:457(__setitem__)
3871073973 511.737 0.000 2363.351 0.000 {built-in method builtins.isinstance}
3869298699 1010.219 0.000 1851.614 0.000 typing.py:1871(__instancecheck__)
3869298702 319.951 0.000 676.984 0.000 <frozen abc>:117(__instancecheck__)
3869298702 357.032 0.000 357.033 0.000 {built-in method _abc._abc_instancecheck}
3869305979/3869305066 164.413 0.000 164.415 0.000 {built-in method builtins.getattr}
472591 51.103 0.000 51.104 0.000 {built-in method builtins.sorted}
472572 2.520 0.000 2.520 0.000 {method 'clear' of 'dict' objects}
478776/472572 0.540 0.000 1.432 0.000 _base.py:337(clone)
472572 0.733 0.000 1.318 0.000 _page.py:849(compute_unique_key)
172625/87450 0.150 0.000 0.916 0.000 _data_structures.py:1435(read_object)