Memory leak in v1.2.8 on Linux ARM64 - When will v1.2.9 be released with the allocator fix?

[michachen]

We're experiencing severe memory leaks when using CatBoost v1.2.8 on Linux ARM64 (aarch64) in production. Memory grows continuously and never gets freed, even though ModelCalcerDelete is being called correctly.

Environment

• CatBoost version: v1.2.8 (precompiled binary: libcatboostmodel-linux-aarch64-1.2.8.so)
• Platform: Linux ARM64 (Kubernetes on GKE)
• Rust binding: catboost-rust 0.3.6

Observed Behavior

• We use this library to load cbm files and use them to predict.
• RSS grows from ~500MB to 12000MB over time. (We load around 3 models and update them every hour, each model is around 200MB to 800MB)
• Memory is never returned to the OS even after models are dropped
• ModelCalcerDelete is called correctly (verified via Rust Drop trait)
• Models are loaded swapped using ArcSwap

Root Cause Investigation

After investigating the source code, I found that the allocator was fixed in commits made after v1.2.8 was released:

1. Initial Fix (July 14, 2025)

Commit: ef3b895bc9

• Switched Linux ARM64 from jemalloc → tcmalloc
• Message: "fix allocator for linux aarch64"

2. Final Fix (July 15, 2025)

Commit: 3570f5146a

• Switched from tcmalloc → system_allocator (glibc malloc)
• Message: "use system allocator by default"

Question

When is v1.2.9 expected to be released?

The v1.2.8 release was on April 12, 2025 (10 months ago), and the allocator fixes are now on the main branch. We need the fixed precompiled binaries to resolve our production memory issues.

Are there any known issues with memory in this library?

[andrey-khropov]

Thank you for bringing attention to this issue.

When is v1.2.9 expected to be released?

I expect it to be released this week.

You can also check out binaries built in GitHub Actions CI from the master branch to confirm that your issues have been resolved.

[michachen]

I actually tried it today 🙂 Downloaded the latest binary and headers. Issue still persists.
Are there any known issues with memory RSS?

Thanks for the response.

[michachen]

@andrey-khropov I also saw some similar issues related to this and were not addressed. Posting them here for any case :)
#1979
#2767

[michachen]

@andrey-khropov Hey quick update here and for anyone who encounters this issue. So I found out theres a new method called LoadFullModelZeroCopy which is not available in v1.2.8. I used most recent un-official release binaries and started to use this method instead of the other load methods. This removes the model from memory immediately when using the rust binding.

[andrey-khropov]

@andrey-khropov Hey quick update here and for anyone who encounters this issue. So I found out theres a new method called LoadFullModelZeroCopy which is not available in v1.2.8. I used most recent un-official release binaries and started to use this method instead of the other load methods. This removes the model from memory immediately when using the rust binding.

CatBoost v1.2.9 that includes this feature has been released.

[michachen]

@andrey-khropov Thanks! Really appreciated :)