Lang Graph Nodes Experience High Latency Unrelated to LLM Execution

[joshuamoreno1]

Checked other resources

• This is a bug, not a usage question. For questions, please use GitHub Discussions.
• I added a clear and detailed title that summarizes the issue.
• I read what a minimal reproducible example is (https://stackoverflow.com/help/minimal-reproducible-example).
• I included a self-contained, minimal example that demonstrates the issue INCLUDING all the relevant imports. The code run AS IS to reproduce the issue.

Example Code

We use langchain default observability.

Error Message and Stack Trace (if applicable)

We don't have an error, the traces are our only evidence.

Description

Hi there,

We're experiencing significant latency in our agent. When analyzing the trace in LangSmith, we notice that LLM operations execute relatively quickly, but the node exhibits unexpectedly high latency with no clear cause. We suspect that the issue might be related to the LangSmith integration, but we have no way to confirm it.

As shown in the attached image, there is a delay of over one second where seemingly nothing is happening.

Any insights or suggestions would be greatly appreciated.

System Info

System Information

OS: Ubuntu
OS Version: Ubuntu 22.04.5 LTS jammy
Python Version: 3.12.8 (main, Dec 3 2024, 18:42:41) [Clang 16.0.0 (clang-1600.0.26.4)]

Package Information

langchain_core: 0.3.29
langchain: 0.3.14
langchain_community: 0.3.14
langsmith: 0.2.10
langchain_anthropic: 0.3.1
langchain_openai: 0.2.14
langchain_text_splitters: 0.3.5
langserve: 0.3.1

Other Dependencies

aiohttp: 3.11.11
anthropic: 0.42.0
async-timeout: Installed. No version info available.
dataclasses-json: 0.6.7
defusedxml: 0.7.1
fastapi: 0.115.6
httpx: 0.28.1
httpx-sse: 0.4.0
jsonpatch: 1.33
langsmith-pyo3: Installed. No version info available.
numpy: 2.2.1
openai: 1.59.7
orjson: 3.10.14
packaging: 24.2
pydantic: 2.10.5
pydantic-settings: 2.7.1
PyYAML: 6.0.2
requests: 2.32.3
requests-toolbelt: 1.0.0
SQLAlchemy: 2.0.37
sse-starlette: 2.2.1
tenacity: 9.0.0
tiktoken: 0.8.0
typing-extensions: 4.12.2
zstandard: Installed. No version info available.

[eyurtsev]

Could you share a snippet that shows what that code is doing? If not, check whether this node is doing additional processing or API calls? Are you using sync / async code?