kvcache-ai / kvcache-ai/Mooncake

[Bug]: mooncake-store offload SSD some question

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bug
Dominant language
C++
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Forks
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Avg merge
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Merged PRs (30d)
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Description

Bug Report

When SSD offload is enabled, I noticed that after writing some keys on Node 1, they get offloaded to the SSD. Later, when I try to read these keys from Node 2, if the key has already been evicted from Node 1’s DRAM but still resides on its SSD, Node 2 will attempt to fetch it. However, Node 2 tries to read directly via the local SSD file path of the key. Since Node 2 obviously does not have this file locally, the read operation fails.

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Research direction

Start by tracing the mooncake-store SSD offload read path, focusing on how Node 2 handles a key that was evicted from Node 1's DRAM but remains on Node 1's SSD. Reproduce the Node 1/Node 2 scenario described in the report and identify where the remote read uses a local SSD path. Done means the key can be fetched successfully from its owning node's SSD.

Written by the indexing model from the issue text.

Assessment

Tech stack
cpp
Domain
distributed-systems
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Quiet
Clarity
Mostly clear
Newbie friendliness
45/100

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