mallopt(M_ARENA_MAX, 4)

[serprex]

No description provided.

[Copilot]

Pull request overview

This PR adds a glibc-specific mallopt(M_ARENA_MAX, 4) call in the background worker startup path to reduce virtual memory usage by limiting glibc malloc arenas before gRPC/Arrow-related threads are created.

Changes:

• Add glibc-only #include <malloc.h> to access mallopt() / M_ARENA_MAX.
• Call mallopt(M_ARENA_MAX, 4) at the start of PschBgworkerMain() (glibc-only) to cap arena growth.

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

[serprex]

with #121 we're fine to set this to 2

[JoshDreamland]

I worry this isn't the full story for cutting back gRPC usage, but seems safe enough to find out.

My main concern was that this should only affect the bgworker, which indeed seems to be the case. Because it's a C++ library, I do worry we could be starting up some gRPC logic in the main process; can't tell that by glancing the code.

[serprex]

full story is #121 but this'll help virtual memory usage on fat instances

[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.