Default batch size potentially too large for OTLP exporter

[kbrockhoff]

Describe the bug
Correctness tests using golden dataset result in error when using the default batch process settings.

Steps to reproduce
Remove this line from correctness_test.go
send_batch_size: 1024

What did you expect to see?
Tests to pass.

What did you see instead?
grpc: received message larger than max (4987657 vs. 4194304)

What version did you use?
Version: 6dcfa47

What config did you use?
Config: See testbed/correctness/correctness_test.go

Environment
OS: OS X
Compiler(if manually compiled): go1.14.3 darwin/amd64

Additional context

[bogdandrutu]

@kbrockhoff the max message size can be configured https://github.com/open-telemetry/opentelemetry-collector/blob/master/config/configgrpc/configgrpc.go#L122 to a larger value if the intent is to support larger batches.

I think this works as expected, gRPC otlp receiver respects the config. I would close this issue but feel free to reopen or start a new issue if this config is not enough.

[cwegener]

For anyone who comes across this post and is wondering what "Line 122" in configgrpc.go actually refers to in Bogdan's comment.
It's this:

opentelemetry-collector/config/configgrpc/configgrpc.go

Lines 128 to 129 in 8a385c2

	// MaxRecvMsgSizeMiB sets the maximum size (in MiB) of messages accepted by the server.
	MaxRecvMsgSizeMiB uint64 `mapstructure:"max_recv_msg_size_mib"`