search

dotnet / runtime

.NET is a cross-platform runtime for cloud, mobile, desktop, and IoT apps.
https://docs.microsoft.com/dotnet/core/
MIT License
14.91k stars 4.63k forks source link

SocketsHttpHandler: Support zero-byte read on response streams #61475

Closed geoffkizer closed 2 years ago

geoffkizer commented 2 years ago

Supporting zero-byte read helps users of these APIs reduce memory usage. It allows them to release their read buffers when no data is currently available.

We should support this in our HTTP response streams in SocketsHttpHandler, including RawConnectionStream since this is used for WebSockets and tunneling scenarios.

Ideally we would also release our own read buffer (if any and if possible) and issue a zero-byte read against the underlying connection. This is what SslStream does (as of 6.0). The idea here is that the user has indicated their interest in minimizing buffer memory usage, and so we should do the same for our own internal buffers.

I split this issue off from https://github.com/dotnet/runtime/issues/61223.

ghost commented 2 years ago

Tagging subscribers to this area: @dotnet/ncl See info in area-owners.md if you want to be subscribed.

Issue Details
Supporting zero-byte read helps users of these APIs reduce memory usage. It allows them to release their read buffers when no data is currently available. We should support this in our HTTP response streams in SocketsHttpHandler, including RawConnectionStream since this is used for WebSockets and tunneling scenarios. Ideally we would also release our own read buffer (if any and if possible) and issue a zero-byte read against the underlying connection. This is what SslStream does (as of 6.0). The idea here is that the user has indicated their interest in minimizing buffer memory usage, and so we should do the same for our own internal buffers. I split this issue off from https://github.com/dotnet/runtime/issues/61223.
Author: geoffkizer
Assignees: -
Labels: `area-System.Net.Http`, `untriaged`
Milestone: -
karelz commented 2 years ago

Triage: We have multiple customers who might benefit from this (savings in COGS) -- gRPC and 2 partner teams.

We might want to double check if SslStream 0-byte reads do not allocate. It might not be 100% working there. We do not have perf coverage here.

karelz commented 2 years ago

Partial fix is also in 6.0.9 (see PR #72804)