feat: add collective communication primitives for CP#182
Open
Chamberlain0w0 wants to merge 1 commit into
Open
Conversation
chen2021673
reviewed
Jul 8, 2026
|
|
||
| // NCCL 2.28.3+ provides native host collective ncclAlltoAll with the same contiguous rank-major layout. | ||
| // Older NCCL releases do not expose it, so fall back to an equivalent grouped ncclSend/ncclRecv schedule. | ||
| #if NCCL_VERSION_CODE >= NCCL_VERSION(2, 28, 3) |
Contributor
There was a problem hiding this comment.
上面#ifndef NCCL_VERSION_CODE #define NCCL_VERSION，这里有 NCCL_VERSION 没有 define 的风险
Contributor
Author
There was a problem hiding this comment.
这个宏应该是 nccl.h 里面定义的，这个文件要编的话也会在编译的一步就检查 nccl.h 了
Contributor
Author
There was a problem hiding this comment.
那似乎 NCCL_VERSION_CODE 和 NCCL_VERSION 这俩本身都无需定义来着
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
新增通信层基础能力，为后续 context parallel 等并行策略提供底层通信算子支持。
主要改动：
CclImpl/NcclImpl中新增AlltoAll接口；在ProcessGroup中新增AlltoAll；在parallel::function中新增 AlltoAll functional wrapper。NcclImpl::AlltoAll支持两路实现：NCCL 2.28.3 及以上使用原生 ncclAlltoAll；低版本 NCCL fallback 到 grouped ncclSend / ncclRecv。torch.distributed.batch_isend_irecv，用于一次性提交一组 p2p send/recv op）：新增P2POpType/P2POp定义，ProcessGroup::BatchSendRecv，复用现有 compute/comm stream event 同步模式，并使用 CCL group 语义提交批量 p2p 操作。