Thread: bug in SlabAlloc / VALGRIND_MAKE_MEM_DEFINED
Hi, Andres nagged to me about valgrind runs taking much longer since 9fab40ad introduced the SlabContext into reorderbuffer.c. And by "longer" I mean hours instead of minutes. After a bit of investigation I stumbled on this line in slab.c: VALGRIND_MAKE_MEM_DEFINED(chunk, SlabChunkGetPointer(chunk)); which is wrong, because the second parameter should be size and not another pointer. This essentially marks a lot of memory as defined, which results in the extreme test runtime. Instead, the line should be: VALGRIND_MAKE_MEM_DEFINED(SlabChunkGetPointer(chunk), sizeof(int32)); Patch attached. -- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
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On 04/04/2017 10:42 PM, Tomas Vondra wrote: > Hi, > > Andres nagged to me about valgrind runs taking much longer since > 9fab40ad introduced the SlabContext into reorderbuffer.c. And by > "longer" I mean hours instead of minutes. > > After a bit of investigation I stumbled on this line in slab.c: > > VALGRIND_MAKE_MEM_DEFINED(chunk, SlabChunkGetPointer(chunk)); > > which is wrong, because the second parameter should be size and not > another pointer. This essentially marks a lot of memory as defined, > which results in the extreme test runtime. > > Instead, the line should be: > > VALGRIND_MAKE_MEM_DEFINED(SlabChunkGetPointer(chunk), sizeof(int32)); > > Patch attached. > Turns out SlabCheck() was missing VALGRIND_MAKE_MEM_DEFINED, resulting in a valgrind failure with --enable-assert. Updated patch version attached, passing all tests in test_decoding. regards -- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
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On 2017-04-04 23:23:30 +0200, Tomas Vondra wrote: > On 04/04/2017 10:42 PM, Tomas Vondra wrote: > > Hi, > > > > Andres nagged to me about valgrind runs taking much longer since > > 9fab40ad introduced the SlabContext into reorderbuffer.c. And by > > "longer" I mean hours instead of minutes. > > > > After a bit of investigation I stumbled on this line in slab.c: > > > > VALGRIND_MAKE_MEM_DEFINED(chunk, SlabChunkGetPointer(chunk)); > > > > which is wrong, because the second parameter should be size and not > > another pointer. This essentially marks a lot of memory as defined, > > which results in the extreme test runtime. > > > > Instead, the line should be: > > > > VALGRIND_MAKE_MEM_DEFINED(SlabChunkGetPointer(chunk), sizeof(int32)); > > > > Patch attached. > > > > Turns out SlabCheck() was missing VALGRIND_MAKE_MEM_DEFINED, resulting in a > valgrind failure with --enable-assert. Updated patch version attached, > passing all tests in test_decoding. Pushed, and re-enabled TestDecoding on skink.