Add profilingSampleCount to decouple profiler sampling source from opCount (#2067)#2067
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Add profilingSampleCount to decouple profiler sampling source from opCount (#2067)#2067mlunar-meta wants to merge 2 commits intometa-pytorch:mainfrom
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…Count (meta-pytorch#2067) Summary: Add a `profilingSampleCount_` pointer on `CtranComm` that allows callers to control which counter the profiler uses for sampling decisions. When set, the profiler samples based on the pointed-to counter instead of opCount. When null (default), existing behavior is preserved — opCount is used. MCCL uses this to sample based on a new `collectiveCount_` counter (incremented per allReduce call) rather than opCount, enabling independent sampling control. Changes: - Add `uint64_t* profilingSampleCount_` to CtranComm (nullptr = use opCount) - Add `uint64_t collectiveCount_` to McclComm, incremented in allReduce - Wire `profilingSampleCount_` to `collectiveCount_` in McclComm::finishInit - Profiler::initForEachColl uses profilingSampleCount when set, else opCount - Add AUTODEPS fix for profiler_test BUCK (ncclx-cvars dep) - Add 2 test cases: override via profilingSampleCount, nullptr fallback to opCount Differential Revision: D100730174
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…Count (meta-pytorch#2067) Summary: Pull Request resolved: meta-pytorch#2067 Add a `profilingSampleCount_` pointer on `CtranComm` that allows callers to control which counter the profiler uses for sampling decisions. When set, the profiler samples based on the pointed-to counter instead of opCount. When null (default), existing behavior is preserved — opCount is used. MCCL uses this to sample based on a new `collectiveCount_` counter (incremented per allReduce call) rather than opCount, enabling independent sampling control. Changes: - Add `uint64_t* profilingSampleCount_` to CtranComm (nullptr = use opCount) - Add `uint64_t collectiveCount_` to McclComm, incremented in allReduce - Wire `profilingSampleCount_` to `collectiveCount_` in McclComm::finishInit - Profiler::initForEachColl uses profilingSampleCount when set, else opCount - Add AUTODEPS fix for profiler_test BUCK (ncclx-cvars dep) - Add 2 test cases: override via profilingSampleCount, nullptr fallback to opCount Differential Revision: D100730174
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Summary: Introduce a SamplingRegistry class in ctran/profiler/ that encapsulates the sampling decision (shouldTrace based on opCount % samplingWeight). The Profiler now reads the sampling weight from ctranConfig at construction instead of receiving it as a parameter at every initForEachColl() call. This decouples the profiler sampling from the hardcoded NCCL_CTRAN_ALGO_PROFILING_SAMPLING_WEIGHT CVAR, allowing MCCL to control its sampling rate independently via a new MCCL_CTRAN_ALGO_PROFILING_SAMPLING_WEIGHT CVAR set on ctranConfig before ctranInit(). Changes: - Add SamplingRegistry class (SamplingRegistry.h/.cc) with shouldTrace(opCount) method - Add profilingSamplingWeight field to ctranConfig (default: NCCL_CTRAN_ALGO_PROFILING_SAMPLING_WEIGHT) - Add MCCL_CTRAN_ALGO_PROFILING_SAMPLING_WEIGHT CVAR (int, default: 1) - Profiler::initForEachColl() no longer takes samplingWeight parameter - Update all 7 algorithm call sites to use simplified initForEachColl(opCount) - MCCL sets profilingSamplingWeight on ctranConfig before ctranInit() - Add SamplingRegistryTest with 5 test cases - Update ProfilerTest to construct Profiler with config-based sampling weight Differential Revision: D100706980
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…Count (meta-pytorch#2067) Summary: Add a `profilingSampleCount_` pointer on `CtranComm` that allows callers to control which counter the profiler uses for sampling decisions. When set, the profiler samples based on the pointed-to counter instead of opCount. When null (default), existing behavior is preserved — opCount is used. MCCL uses this to sample based on a new `collectiveCount_` counter (incremented per allReduce call) rather than opCount, enabling independent sampling control. Changes: - Add `uint64_t* profilingSampleCount_` to CtranComm (nullptr = use opCount) - Add `uint64_t collectiveCount_` to McclComm, incremented in allReduce - Wire `profilingSampleCount_` to `collectiveCount_` in McclComm::finishInit - Profiler::initForEachColl uses profilingSampleCount when set, else opCount - Add AUTODEPS fix for profiler_test BUCK (ncclx-cvars dep) - Add 2 test cases: override via profilingSampleCount, nullptr fallback to opCount Differential Revision: D100730174
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…Count (meta-pytorch#2067) Summary: Pull Request resolved: meta-pytorch#2067 Add a `profilingSampleCount_` pointer on `CtranComm` that allows callers to control which counter the profiler uses for sampling decisions. When set, the profiler samples based on the pointed-to counter instead of opCount. When null (default), existing behavior is preserved — opCount is used. MCCL uses this to sample based on a new `collectiveCount_` counter (incremented per allReduce call) rather than opCount, enabling independent sampling control. Changes: - Add `uint64_t* profilingSampleCount_` to CtranComm (nullptr = use opCount) - Add `uint64_t collectiveCount_` to McclComm, incremented in allReduce - Wire `profilingSampleCount_` to `collectiveCount_` in McclComm::finishInit - Profiler::initForEachColl uses profilingSampleCount when set, else opCount - Add AUTODEPS fix for profiler_test BUCK (ncclx-cvars dep) - Add 2 test cases: override via profilingSampleCount, nullptr fallback to opCount Differential Revision: D100730174
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Summary:
Add a
profilingSampleCount_pointer onCtranCommthat allows callers to control which counter the profiler uses for sampling decisions. When set, the profiler samples based on the pointed-to counter instead of opCount. When null (default), existing behavior is preserved — opCount is used.MCCL uses this to sample based on a new
collectiveCount_counter (incremented per allReduce call) rather than opCount, enabling independent sampling control.Changes:
uint64_t* profilingSampleCount_to CtranComm (nullptr = use opCount)uint64_t collectiveCount_to McclComm, incremented in allReduceprofilingSampleCount_tocollectiveCount_in McclComm::finishInitDifferential Revision: D100730174