Use ncclx::Hints for NCCLx-specific config#1017
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pavanbalaji wants to merge 4 commits intometa-pytorch:mainfrom
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Use ncclx::Hints for NCCLx-specific config#1017pavanbalaji wants to merge 4 commits intometa-pytorch:mainfrom
pavanbalaji wants to merge 4 commits intometa-pytorch:mainfrom
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Summary: Pull Request resolved: meta-pytorch#1017 In populateNcclConfigFromHints, NCCLx-specific parameters (ncclAllGatherAlgo, lazySetupChannels, fastInitMode) were being set directly on the ncclConfig_t struct fields. This bypasses the ncclx::Hints API which is the intended mechanism for passing NCCLx-specific configuration. Change upstream NCCL config fields (blocking, cgaClusterSize, minCTAs, etc.) to continue being set directly on the config struct, while NCCLx-specific fields are now passed via an ncclx::Hints object attached to config.hints. Also update isFastInitEnable/useFastInit to check the hints object for fastInitMode since it is no longer set directly on the config struct. Reviewed By: minsii Differential Revision: D95972679
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Summary: Pull Request resolved: meta-pytorch#1017 In populateNcclConfigFromHints, NCCLx-specific parameters (ncclAllGatherAlgo, lazySetupChannels, fastInitMode) were being set directly on the ncclConfig_t struct fields. This bypasses the ncclx::Hints API which is the intended mechanism for passing NCCLx-specific configuration. Change upstream NCCL config fields (blocking, cgaClusterSize, minCTAs, etc.) to continue being set directly on the config struct, while NCCLx-specific fields are now passed via an ncclx::Hints object attached to config.hints. Also update isFastInitEnable/useFastInit to check the hints object for fastInitMode since it is no longer set directly on the config struct. Reviewed By: minsii Differential Revision: D95972679
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Summary: Each public comm-creation API now immediately creates a guaranteed non-null internalConfigPtr (using the user-passed config or a default) and calls ncclxParseCommConfig on it. This ensures each communicator gets a freshly allocated ncclx::Config with sole ownership, preventing a double-free when callers reuse the same ncclConfig_t for multiple comms. Public APIs updated: ncclCommInitRank, ncclCommInitAll, ncclCommInitRankConfig, ncclCommInitRankScalable, ncclCommSplit, ncclCommShrink, and ncclCommGrow (v2_29). Inside ncclxParseCommConfig, assert that config is non-null and ncclxConfig is still at NCCL_CONFIG_UNDEF_PTR, rather than silently returning or doing an idempotency check. Removed ncclxParseCommConfig call from ncclCommInitChildComm (private helper) since the public caller already did it. Reviewed By: minsii Differential Revision: D95714601
Summary: Add unit tests exercising ncclxParseCommConfig, covering flat ncclConfig_t fields, hints-based configuration, default values, idempotency, and conflict detection between flat fields and hints. Applied identically to v2_27, v2_28, and v2_29. Reviewed By: minsii Differential Revision: D95714600
Summary: Strip the "ncclx::" prefix in Hints::set() and Hints::get() so that callers can use either "fastInitMode" or "ncclx::fastInitMode" interchangeably. The prefix is stripped before key matching, storage, and lookup, so the internal map always uses bare key names (compatible with ncclxParseCommConfig). Reviewed By: minsii Differential Revision: D95972681
Summary: In populateNcclConfigFromHints, NCCLx-specific parameters (ncclAllGatherAlgo, lazySetupChannels, fastInitMode) were being set directly on the ncclConfig_t struct fields. This bypasses the ncclx::Hints API which is the intended mechanism for passing NCCLx-specific configuration. Change upstream NCCL config fields (blocking, cgaClusterSize, minCTAs, etc.) to continue being set directly on the config struct, while NCCLx-specific fields are now passed via an ncclx::Hints object attached to config.hints. Also update isFastInitEnable/useFastInit to check the hints object for fastInitMode since it is no longer set directly on the config struct. Reviewed By: minsii Differential Revision: D95972679
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Summary:
In populateNcclConfigFromHints, NCCLx-specific parameters
(ncclAllGatherAlgo, lazySetupChannels, fastInitMode) were being
set directly on the ncclConfig_t struct fields. This bypasses the
ncclx::Hints API which is the intended mechanism for passing
NCCLx-specific configuration.
Change upstream NCCL config fields (blocking, cgaClusterSize,
minCTAs, etc.) to continue being set directly on the config
struct, while NCCLx-specific fields are now passed via an
ncclx::Hints object attached to config.hints.
Also update isFastInitEnable/useFastInit to check the hints
object for fastInitMode since it is no longer set directly on
the config struct.
Differential Revision: D95972679