Author vstinner
Recipients catalin.manciu, florin.papa, vstinner
Date 2016-02-19.11:12:44
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Message-id <1455880365.01.0.0599772710283.issue26382@psf.upfronthosting.co.za>
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"Theoretically, an object type that consistently allocates more than the small object threshold would perform a bit slower because it would first jump to the small object allocator, do the size comparison and then jump to malloc."

I expect that the cost of the extra check is *very* cheap (completly negligible) compared to the cost of a call to malloc().

To have an idea of the cost of the Python code around system allocators, you can take a look at the Performance section of my PEP 445 which added an indirection to all Python allocators:
https://www.python.org/dev/peps/pep-0445/#performances

I was unable to measure an overhead on macro benchmarks (perf.py). The overhead on microbenchmarks was really hard to measure because it was so low that benchmarks were very unable.
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Date User Action Args
2016-02-19 11:12:45vstinnersetrecipients: + vstinner, florin.papa, catalin.manciu
2016-02-19 11:12:45vstinnersetmessageid: <1455880365.01.0.0599772710283.issue26382@psf.upfronthosting.co.za>
2016-02-19 11:12:44vstinnerlinkissue26382 messages
2016-02-19 11:12:44vstinnercreate