Limit of 4M on outgoing messages

[MathieuDutSik]

Bug Report

There is a limit on ongoing messages sent to a server of 4M that we can see in many different implementations. However, tonic also implements a limitation of 4M on outgoing messages. That limitation is rarer and maybe not justified.

Version

0.11

Platform

Crates

Description

[mladedav]

For anyone stumbling upon this, you can set your limits directly on the Grpc type like so:

            let grpc = tonic::client::Grpc::new(svc)
                .max_decoding_message_size(usize::MAX)
                .max_encoding_message_size(usize::MAX);

The question here should be whether there should be a default limit and if so whether it should be 4 MiB.

[ajwerner]

The question here should be whether there should be a default limit and if so whether it should be 4 MiB.

I don't know if this is worth having open as an issue to ask. Seems like this is the default for all of the implementations, and its configurable. I vote we just close this.

• C/C++: https://github.com/grpc/grpc/blob/14d76aac59df4be97adbba1dea93d3d6fe058eed/include/grpc/impl/grpc_types.h#L180
• C#: https://github.com/grpc/grpc-dotnet/blob/b57c87f2a9897b2046fdf8fff8e9eb5cb5bce396/src/Grpc.Net.Client/GrpcChannel.cs#L44
• Go: https://github.com/grpc/grpc-go/blob/6d236200ea68ea644d78a164c4ad9952a765aed3/clientconn.go#L96
• https://github.com/grpc/grpc-java/blob/a28357e197e2085b21683fe89b850c7e91cbe5a3/core/src/main/java/io/grpc/internal/GrpcUtil.java#L211-L214

[mladedav]

@ajwerner all links you sent are defaults for received messages. Default for size of outgoing messages is -1 in C/C++ and Math.MaxInt32 in Go, I didn't see similar constants in C# and Java.

For me this issue isn't about the default max size of received messages, but about tonic refusing to send large messages because of this limit.