[BUG]: Thread pool lru cache

[tazarov]

Description of changes

The problem stems from how AnyIO handles synchronous calls when back pressure is on uvicorn. As it turns out, threads from the pool are used (max is 40); however, the thread contexts change, which causes the Connections to no longer be linked to thread-local but remain in the _connections set of the pool, leading to an infinite growth of open file handles (one per Connection). To solve this, an LRU cache is introduced to keep track of and clean up Connections that are not used for a configurable amount of time.

Summarize the changes made by this PR.

• Improvements & Bug fixes
  • LRU cache in the PerThread SQLite connection pool

Test plan

How are these changes tested?

• Tests pass locally with pytest for python, yarn test for js

Documentation Changes

N/A

[github-actions]

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Quality

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[jasdeepsngh576]

When is this fix going to be released. We are facing similar issue where file handles are growing infinitely even for global chroma client.

[mrityunjayupadhyay]

We are running this issue frequently. Kindly give an ETA of fix.

[tazarov]

@HammadB, wdyt, does the PR make sense?

[tazarov]

Try to see if #1938 resolves this.

[tazarov]

Try to see if #1938 resolves this.

After testing with a Chroma community member in a prod/prod-like environment, I can confirm that #1938 does not resolve the issue.

[tazarov]

Closing this in favor of #2014