gh-75876: Correct the memory use declared by some bigmem tests - #155307
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Measured with a limited address space and the peak RSS of the process: * TupleTest.test_repeat_large_2 keeps 3 tuples of pointers alive, as its siblings do, but declared the count for a 32-bit build. * The md5 tests hash the data and a io.BytesIO() copy of it. * testDecompress4G keeps the data, the compressed and the decompressed bytes alive, and the decompressor grows its output buffer. * test_huge_string_builtins uses 3 times the string size, not 2. * test_large_subn uses a bit more than the 18 times it declared. Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
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needs backport to 3.13
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Thanks @serhiy-storchaka for the PR 🌮🎉.. I'm working now to backport this PR to: 3.13, 3.14, 3.15. |
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GH-155312 is a backport of this pull request to the 3.15 branch. |
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needs backport to 3.15
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GH-155313 is a backport of this pull request to the 3.14 branch. |
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GH-155314 is a backport of this pull request to the 3.13 branch. |
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…GH-155307) (GH-155314) Measured with a limited address space and the peak RSS of the process: * TupleTest.test_repeat_large_2 keeps 3 tuples of pointers alive, as its siblings do, but declared the count for a 32-bit build. * The md5 tests hash the data and a io.BytesIO() copy of it. * testDecompress4G keeps the data, the compressed and the decompressed bytes alive, and the decompressor grows its output buffer. * test_huge_string_builtins uses 3 times the string size, not 2. * test_large_subn uses a bit more than the 18 times it declared. (cherry picked from commit e469fa9) Co-authored-by: Serhiy Storchaka <storchaka@gmail.com> Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
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…GH-155307) (GH-155313) Measured with a limited address space and the peak RSS of the process: * TupleTest.test_repeat_large_2 keeps 3 tuples of pointers alive, as its siblings do, but declared the count for a 32-bit build. * The md5 tests hash the data and a io.BytesIO() copy of it. * testDecompress4G keeps the data, the compressed and the decompressed bytes alive, and the decompressor grows its output buffer. * test_huge_string_builtins uses 3 times the string size, not 2. * test_large_subn uses a bit more than the 18 times it declared. (cherry picked from commit e469fa9) Co-authored-by: Serhiy Storchaka <storchaka@gmail.com> Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
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Some bigmem tests declare less memory than they use. Measured as the peak RSS of a process running a single test with
-M:TupleTest.test_repeat_large_2HashLibTestCase.test_case_md5_hugeHashLibTestCase.test_case_md5_uintmaxZlibDecompressorTest.testDecompress4GBigmemTclTest.test_huge_string_builtinsReTests.test_large_subntest_repeat_large_2keeps 3 tuples of pointers alive, astest_repeat_smallandtest_repeat_largedo, but declared12instead ofpointer_size * 3, which is the count for a 32-bit build.The md5 tests pass the data to
check_file_digest(), which copies all of it into anio.BytesIO().testDecompress4Gkeeps the data, the compressed and the decompressed bytes alive at the same time, and the decompressor grows its output buffer.These are the only tests which use more memory than they declare. The other 227 bigmem tests were measured too: the largest excess is 1.03x, and it is 20 MiB in the median.