EHDRSZ grpc protocol_error ai_generated true

INTERNAL: grpc: header size exceeds max limit of 8192 bytes

ID: grpc/header-too-large

Also available as: JSON · Markdown · 中文
80%Fix Rate
85%Confidence
1Evidence
2024-05-20First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
gRPC v1.61.0 active — — —
gRPC v1.58.0 active — — —
gRPC v1.55.0 active — — —
C++ gRPC v1.50.0 active — — —

Root Cause

gRPC metadata (headers) sent in a single RPC call exceeds the default 8KB limit enforced by the gRPC framework.

generic

中文

单个 RPC 调用中发送的 gRPC 元数据（标头）超过了 gRPC 框架强制执行的默认 8KB 限制。

Official Documentation

https://grpc.io/docs/guides/error-handling/#header-size-limit

Workarounds

  1. 85% success Increase the max header size on both client and server via channel option: `grpc.max_metadata_size=16384` in Python, or `GRPC_ARG_MAX_METADATA_SIZE` in C++. 
    Increase the max header size on both client and server via channel option: `grpc.max_metadata_size=16384` in Python, or `GRPC_ARG_MAX_METADATA_SIZE` in C++.
  2. 75% success Reduce metadata size by splitting large metadata across multiple RPCs or using a separate side channel for large data. 
    Reduce metadata size by splitting large metadata across multiple RPCs or using a separate side channel for large data.

中文步骤

  1. 在客户端和服务器上通过通道选项增加最大标头大小：Python 中使用 `grpc.max_metadata_size=16384`，C++ 中使用 `GRPC_ARG_MAX_METADATA_SIZE`。
  2. 通过将大型元数据拆分到多个 RPC 或使用单独的侧通道传输大型数据来减少元数据大小。

Dead Ends

Common approaches that don't work:

  1. Increasing server-side max header size only 70% fail

    The limit is enforced on both client and server; both sides must agree.

  2. Compressing metadata using gRPC compression 95% fail

    Metadata is not compressed by gRPC compression; only message payload is.

  3. Sending metadata in the message body instead 80% fail

    Metadata is designed for headers; moving it to body breaks protocol semantics.