Currently, the max number of in-flight requests in the proxy is
unbounded. This is due to the `Buffer` middleware being unbounded.
This is resolved by adding an instance of `InFlightLimit` around
`Buffer`, capping the max number of in-flight requests for a given
endpoint.
Currently, the limit is hardcoded to 10,000. However, this will
eventually become a configuration value.
Fixes#287
Signed-off-by: Carl Lerche <me@carllerche.com>
Currently, the conduit proxy uses a simplistic Round-Robin load
balancing algorithm. This strategy degrades severely when individual
endpoints exhibit abnormally high latency.
This change improves this situation somewhat by making the load balancer
aware of the number of outstanding requests to each endpoint. When nodes
exhibit high latency, they should tend to have more pending requests
than faster nodes; and the Power-of-Two-Choices node selector can be
used to distribute requests to lesser-loaded instances.
From the finagle guide:
The algorithm randomly picks two nodes from the set of ready endpoints
and selects the least loaded of the two. By repeatedly using this
strategy, we can expect a manageable upper bound on the maximum load of
any server.
The maximum load variance between any two servers is bound by
ln(ln(n))` where `n` is the number of servers in the cluster.
Signed-off-by: Oliver Gould <ver@buoyant.io>
The proxy depends on `protoc`-generated gRPC bindings to communicate
with the controller. In order to generate these bindings, build-time
dependencies must be compiled.
In order to support a more granular, cacheable build scheme, a new crate
has been created to house these gRPC bindings,
`conduit-proxy-controller-grpc`.
Because `TryFrom` and `TryInto` conversions are implemented for
protobuf-defined types, the `convert` module also had to be moved to
into a dedicated crate.
Furthermore, because the proxy's tests require that
`quickcheck::Aribtrary` be implemented for protobuf types, the
`conduit-proxy-controller-grpc` crate supports an _arbitrary_ feature
fla protobuf types, the `conduit-proxy-controller-grpc` crate supports
an _arbitrary_ feature flag.
While we're moving these libraries around, the `tower-router` crate has
been moved to `proxy/router` and renamed to `conduit-proxy-router.`
`futures-mpsc-lossy` has been moved into the proxy directory but has not
been renamed.
Finally, the `proxy/Dockerfile-deps` image has been updated to avoid the
wasteful building of dependency artifacts, as they are not actually used
by `proxy/Dockerfile`.
The conduit repo includes several library projects that have since been
moved into external repos, including `tower-grpc` and `tower-h2`.
This change removes these vendored libraries in favor of using the new
external crates.
The proxy will now try to detect what protocol new connections are
using, and route them accordingly. Specifically:
- HTTP/2 stays the same.
- HTTP/1 is now accepted, and will try to send an HTTP/1 request
to the target.
- If neither HTTP/1 nor 2, assume a TCP stream and simply forward
between the source and destination.
* tower-h2: fix Server Clone bounds
* proxy: implement Async{Read,Write} extra methods for Connection
Closes#130Closes#131
We’ve built Conduit from the ground up to be the fastest, lightest,
simplest, and most secure service mesh in the world. It features an
incredibly fast and safe data plane written in Rust, a simple yet
powerful control plane written in Go, and a design that’s focused on
performance, security, and usability. Most importantly, Conduit
incorporates the many lessons we’ve learned from over 18 months of
production service mesh experience with Linkerd.
This repository contains a few tightly-related components:
- `proxy` -- an HTTP/2 proxy written in Rust;
- `controller` -- a control plane written in Go with gRPC;
- `web` -- a UI written in React, served by Go.
Eliza Weisman
Kevin Lingerfelt
Carl Lerche
Oliver Gould
Dennis Adjei-Baah
Sean McArthur
Andrew Seigner