gRPC 0 OK vs 4 DEADLINE_EXCEEDED
Both gRPC 0 (OK) and 4 (DEADLINE_EXCEEDED) belong to the gRPC Status Codes category. 0 indicates that the operation completed successfully. Not an error; returned on success. Meanwhile, 4 means that the deadline expired before the operation could complete. For operations that change the state of the system, this error may be returned even if the operation has completed successfully.
Description
The operation completed successfully. Not an error; returned on success.
When You See It
The RPC completed without any issues. This is the expected response for every successful gRPC call.
How to Fix
No fix needed — this indicates everything worked correctly.
Description
The deadline expired before the operation could complete. For operations that change the state of the system, this error may be returned even if the operation has completed successfully.
When You See It
The RPC took longer than the configured deadline allows. Common in slow network conditions, overloaded servers, or when the deadline is set too aggressively.
How to Fix
Increase the client deadline, optimize the server-side processing, or add server-side caching. If the operation might have succeeded, check idempotency before retrying.
Key Differences
gRPC 0: The operation completed successfully. Not an error; returned on success.
gRPC 4: The deadline expired before the operation could complete. For operations that change the state of the system, this error may be returned even if the operation has completed successfully.
You encounter 0 when the RPC completed without any issues. This is the expected response for every successful gRPC call.
You encounter 4 when the RPC took longer than the configured deadline allows. Common in slow network conditions, overloaded servers, or when the deadline is set too aggressively.
When to Use Which
For 0 (OK): No fix needed — this indicates everything worked correctly. For 4 (DEADLINE_EXCEEDED): Increase the client deadline, optimize the server-side processing, or add server-side caching. If the operation might have succeeded, check idempotency before retrying.