[PR #337] [MERGED] fix(store): the metadata leak after umount segment #1490

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opened 2026-10-29 21:27:55 +00:00 by bsakaguchi · 0 comments

bsakaguchi commented

2026-10-29 21:27:55 +00:00

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📋 Pull Request Information

Original PR: https://github.com/kvcache-ai/Mooncake/pull/337
Author: @maobaolong
Created: 5/8/2025
Status: ✅ Merged
Merged: 5/15/2025
Merged by: @stmatengss

Base: main ← Head: fixUnmountLeak

📝 Commits (2)

b85e278 fix the metadata leak after umount segment
5d4c261 Add a performance test

📊 Changes

3 files changed (+173 additions, -1 deletions)

View changed files

📝 mooncake-store/include/master_service.h (+6 -0)
📝 mooncake-store/src/master_service.cpp (+38 -1)
📝 mooncake-store/tests/master_service_test.cpp (+129 -0)

📄 Description

Description

Although UnmountSegement remove the specified segment from buffer_allocator_manager, but the related metadata of objects still exists.

Although MetadataAccessor will remove these invalid key in the constructor, but it will still leak if the related keys do not be accessed any more.

So the safe way is remove the related keys in the UnmountSegement function.

Future work

It would be better to collect the UnmountSegement request and execute it async.

_{🔄 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/337 **Author:** [@maobaolong](https://github.com/maobaolong) **Created:** 5/8/2025 **Status:** ✅ Merged **Merged:** 5/15/2025 **Merged by:** [@stmatengss](https://github.com/stmatengss) **Base:** `main` ← **Head:** `fixUnmountLeak` --- ### 📝 Commits (2) - [`b85e278`](https://github.com/kvcache-ai/Mooncake/commit/b85e278219d264021847d51b448821fe7be4fe1d) fix the metadata leak after umount segment - [`5d4c261`](https://github.com/kvcache-ai/Mooncake/commit/5d4c261884cab54545a67bc52678b23f074afe0e) Add a performance test ### 📊 Changes **3 files changed** (+173 additions, -1 deletions) <details> <summary>View changed files</summary> 📝 `mooncake-store/include/master_service.h` (+6 -0) 📝 `mooncake-store/src/master_service.cpp` (+38 -1) 📝 `mooncake-store/tests/master_service_test.cpp` (+129 -0) </details> ### 📄 Description # Description Although `UnmountSegement` remove the specified segment from buffer_allocator_manager, but the related metadata of objects still exists. Although `MetadataAccessor` will remove these invalid key in the constructor, but it will still leak if the related keys do not be accessed any more. So the safe way is remove the related keys in the UnmountSegement function. # Future work - It would be better to collect the `UnmountSegement` request and execute it async. --- <sub>🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.</sub>

bsakaguchi

2026-10-29 21:27:55 +00:00