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2021-12-13tests: fix broken &&-chains in `{...}` groupsEric Sunshine
The top-level &&-chain checker built into t/test-lib.sh causes tests to magically exit with code 117 if the &&-chain is broken. However, it has the shortcoming that the magic does not work within `{...}` groups, `(...)` subshells, `$(...)` substitutions, or within bodies of compound statements, such as `if`, `for`, `while`, `case`, etc. `chainlint.sed` partly fills in the gap by catching broken &&-chains in `(...)` subshells, but bugs can still lurk behind broken &&-chains in the other cases. Fix broken &&-chains in `{...}` groups in order to reduce the number of possible lurking bugs. Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> Reviewed-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-07tests: fix a memory leak in test-oidtree.cÆvar Arnfjörð Bjarmason
Fix a memory leak in t/helper/test-oidtree.c, we were not freeing the "struct strbuf" we used for the stdin input we parsed. This leak has been here ever since 92d8ed8ac10 (oidtree: a crit-bit tree for odb_loose_cache, 2021-07-07). Now that it's fixed we can declare that t0069-oidtree.sh will pass under GIT_TEST_PASSING_SANITIZE_LEAK=true. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-07-08oidtree: a crit-bit tree for odb_loose_cacheEric Wong
This saves 8K per `struct object_directory', meaning it saves around 800MB in my case involving 100K alternates (half or more of those alternates are unlikely to hold loose objects). This is implemented in two parts: a generic, allocation-free `cbtree' and the `oidtree' wrapper on top of it. The latter provides allocation using alloc_state as a memory pool to improve locality and reduce free(3) overhead. Unlike oid-array, the crit-bit tree does not require sorting. Performance is bound by the key length, for oidtree that is fixed at sizeof(struct object_id). There's no need to have 256 oidtrees to mitigate the O(n log n) overhead like we did with oid-array. Being a prefix trie, it is natively suited for expanding short object IDs via prefix-limited iteration in `find_short_object_filename'. On my busy workstation, p4205 performance seems to be roughly unchanged (+/-8%). Startup with 100K total alternates with no loose objects seems around 10-20% faster on a hot cache. (800MB in memory savings means more memory for the kernel FS cache). The generic cbtree implementation does impose some extra overhead for oidtree in that it uses memcmp(3) on "struct object_id" so it wastes cycles comparing 12 extra bytes on SHA-1 repositories. I've not yet explored reducing this overhead, but I expect there are many places in our code base where we'd want to investigate this. More information on crit-bit trees: https://cr.yp.to/critbit.html Signed-off-by: Eric Wong <e@80x24.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>