[PR #1259] [MERGED] add MC_FORCE_HCA environment variable to force use rdma

No labels

No milestone

No project

No assignees

1 participant

Notifications

Due date

The due date is invalid or out of range. Please use the format "yyyy-mm-dd".

No due date set.

Dependencies

No dependencies set.

Reference

kvcache-ai/Mooncake#2113

bsakaguchi commented

2026-10-29 21:32:52 +00:00

Owner

📋 Pull Request Information

Original PR: https://github.com/kvcache-ai/Mooncake/pull/1259
Author: @baymaxhuang
Created: 12/22/2025
Status: ✅ Merged
Merged: 12/23/2025
Merged by: @stmatengss

Base: main ← Head: dev

📝 Commits (3)

1b5fc28 add MC_FORCE_HCA environment variable to force use rdma
61dc71c Updater for better readability
4e0ce48 fix clang-format problem

📊 Changes

3 files changed (+10 additions, -2 deletions)

View changed files

📝 docs/source/design/transfer-engine/index.md (+1 -0)
📝 docs/source/zh_archive/transfer-engine.md (+1 -0)
📝 mooncake-transfer-engine/src/transfer_engine.cpp (+8 -2)

📄 Description

Description

In production environment, RDAM is usually needed to provide an efficent transport. But when a user provides a wrong HCA list, mooncake transport will be fallback to TCP. It will cause some unexpected performace problem. In this patch, we add a new environment varible to force to use RDMA as the active transport, it will return error if no HCA has been found.

Type of Change

Types
- Bug fix
- New feature
  - Transfer Engine
  - Mooncake Store
  - Mooncake EP
  - Integration
  - P2P Store
  - Python Wheel
- Breaking change
- CI/CD
- Documentation update
- Other

How Has This Been Tested?

Checklist

I have performed a self-review of my own code.
I have updated the documentation.
I have added tests to prove my changes are effective.

_{🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.}

## 📋 Pull Request Information **Original PR:** https://github.com/kvcache-ai/Mooncake/pull/1259 **Author:** [@baymaxhuang](https://github.com/baymaxhuang) **Created:** 12/22/2025 **Status:** ✅ Merged **Merged:** 12/23/2025 **Merged by:** [@stmatengss](https://github.com/stmatengss) **Base:** `main` ← **Head:** `dev` --- ### 📝 Commits (3) - [`1b5fc28`](https://github.com/kvcache-ai/Mooncake/commit/1b5fc28c921433087d45e84f8c3c3d88fa87d77e) add MC_FORCE_HCA environment variable to force use rdma - [`61dc71c`](https://github.com/kvcache-ai/Mooncake/commit/61dc71ca83ffa07981ebd2ce87b365ec01c92196) Updater for better readability - [`4e0ce48`](https://github.com/kvcache-ai/Mooncake/commit/4e0ce488afcba624a2b3225af790c29b22a5dd65) fix clang-format problem ### 📊 Changes **3 files changed** (+10 additions, -2 deletions) <details> <summary>View changed files</summary> 📝 `docs/source/design/transfer-engine/index.md` (+1 -0) 📝 `docs/source/zh_archive/transfer-engine.md` (+1 -0) 📝 `mooncake-transfer-engine/src/transfer_engine.cpp` (+8 -2) </details> ### 📄 Description ## Description In production environment, RDAM is usually needed to provide an efficent transport. But when a user provides a wrong HCA list, mooncake transport will be fallback to TCP. It will cause some unexpected performace problem. In this patch, we add a new environment varible to force to use RDMA as the active transport, it will return error if no HCA has been found.  ## Type of Change * Types - [ ] Bug fix - [x] New feature - [x] Transfer Engine - [ ] Mooncake Store - [ ] Mooncake EP - [ ] Integration - [ ] P2P Store - [ ] Python Wheel - [ ] Breaking change - [ ] CI/CD - [ ] Documentation update - [ ] Other ## How Has This Been Tested?  ## Checklist - [x] I have performed a self-review of my own code. - [x] I have updated the documentation. - [ ] I have added tests to prove my changes are effective. --- <sub>🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.</sub>

bsakaguchi

closed this issue
added the
pull-request
label

Rows
Columns

[PR #1259] [MERGED] add MC_FORCE_HCA environment variable to force use rdma #2113