proxy: Use a PeakEWMA outbound load balancer (#1080)
`tower-balance` has been updated with a Peak-EWMA load balancer; and a new crate, `tower-h2-balance` has been introduced to make the load balancer aware of some H2 stream events. The Peak-EWMA balancer is designed to reduce tail latency by maintaining an Exponentially Weighted Moving Average of latencies to each endpoint which decay over a 10s window.
This commit is contained in:
Oliver Gould
GitHub
parent
0687665444
commit
2ed7c4ad40
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@ -149,7 +149,7 @@ dependencies = [
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"regex 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
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"ring 0.13.0-alpha4 (registry+https://github.com/rust-lang/crates.io-index)",
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"rustls 0.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-connect 0.1.0 (git+https://github.com/carllerche/tokio-connect)",
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"tokio-io 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-rustls 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
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@ -159,6 +159,7 @@ dependencies = [
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"tower-discover 0.1.0 (git+https://github.com/tower-rs/tower)",
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"tower-grpc 0.1.0 (git+https://github.com/tower-rs/tower-grpc)",
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"tower-h2 0.1.0 (git+https://github.com/tower-rs/tower-h2)",
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"tower-h2-balance 0.1.0 (git+https://github.com/tower-rs/tower-h2)",
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"tower-in-flight-limit 0.1.0 (git+https://github.com/tower-rs/tower)",
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"tower-reconnect 0.1.0 (git+https://github.com/tower-rs/tower)",
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"tower-service 0.1.0 (git+https://github.com/tower-rs/tower)",
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@ -433,12 +434,12 @@ dependencies = [
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"log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
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"net2 0.2.32 (registry+https://github.com/rust-lang/crates.io-index)",
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"time 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-executor 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-io 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-reactor 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-tcp 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-timer 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-timer 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
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"want 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
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]
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@ -1029,7 +1030,7 @@ dependencies = [
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[[package]]
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name = "tokio"
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version = "0.1.6"
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version = "0.1.7"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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dependencies = [
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"futures 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
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@ -1039,8 +1040,8 @@ dependencies = [
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"tokio-io 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-reactor 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-tcp 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-threadpool 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-timer 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-threadpool 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-timer 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-udp 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
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]
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@ -1068,7 +1069,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
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dependencies = [
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"futures 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-io 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-threadpool 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-threadpool 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
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]
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[[package]]
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@ -1100,7 +1101,7 @@ version = "0.6.0"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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dependencies = [
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"rustls 0.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
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"webpki 0.18.0-alpha4 (registry+https://github.com/rust-lang/crates.io-index)",
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]
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@ -1134,7 +1135,7 @@ dependencies = [
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[[package]]
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name = "tokio-threadpool"
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version = "0.1.3"
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version = "0.1.4"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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dependencies = [
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"crossbeam-deque 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
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@ -1147,7 +1148,7 @@ dependencies = [
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[[package]]
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name = "tokio-timer"
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version = "0.2.3"
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version = "0.2.4"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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dependencies = [
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"futures 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
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@ -1170,12 +1171,13 @@ dependencies = [
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[[package]]
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name = "tower-balance"
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version = "0.1.0"
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source = "git+https://github.com/tower-rs/tower#9d49396eb807e6913c46cd877d6f8d039d3d5e1d"
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source = "git+https://github.com/tower-rs/tower#fcdc9d27777d82ab75e58aa67ff2aac1b89ccc82"
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dependencies = [
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"futures 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
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"indexmap 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
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"log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
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"rand 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
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"rand 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-timer 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
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"tower-discover 0.1.0 (git+https://github.com/tower-rs/tower)",
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"tower-service 0.1.0 (git+https://github.com/tower-rs/tower)",
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]
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@ -1192,7 +1194,7 @@ dependencies = [
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[[package]]
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name = "tower-discover"
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version = "0.1.0"
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source = "git+https://github.com/tower-rs/tower#9d49396eb807e6913c46cd877d6f8d039d3d5e1d"
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source = "git+https://github.com/tower-rs/tower#fcdc9d27777d82ab75e58aa67ff2aac1b89ccc82"
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dependencies = [
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"futures 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
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"tower-service 0.1.0 (git+https://github.com/tower-rs/tower)",
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@ -1226,7 +1228,7 @@ dependencies = [
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[[package]]
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name = "tower-h2"
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version = "0.1.0"
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source = "git+https://github.com/tower-rs/tower-h2#abb40873322af7c014d2cb3a4caf03f5f88175e9"
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source = "git+https://github.com/tower-rs/tower-h2#760f9fc1c83c3a96edb6fbddb6b0cd3cac73d8ac"
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dependencies = [
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"bytes 0.4.7 (registry+https://github.com/rust-lang/crates.io-index)",
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"futures 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
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@ -1238,6 +1240,19 @@ dependencies = [
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"tower-service 0.1.0 (git+https://github.com/tower-rs/tower)",
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]
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[[package]]
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name = "tower-h2-balance"
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version = "0.1.0"
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source = "git+https://github.com/tower-rs/tower-h2#760f9fc1c83c3a96edb6fbddb6b0cd3cac73d8ac"
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dependencies = [
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"futures 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
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"h2 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
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"http 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
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"tower-balance 0.1.0 (git+https://github.com/tower-rs/tower)",
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"tower-h2 0.1.0 (git+https://github.com/tower-rs/tower-h2)",
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"tower-service 0.1.0 (git+https://github.com/tower-rs/tower)",
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]
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[[package]]
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name = "tower-in-flight-limit"
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version = "0.1.0"
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@ -1260,7 +1275,7 @@ dependencies = [
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[[package]]
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name = "tower-service"
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version = "0.1.0"
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source = "git+https://github.com/tower-rs/tower#9d49396eb807e6913c46cd877d6f8d039d3d5e1d"
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source = "git+https://github.com/tower-rs/tower#fcdc9d27777d82ab75e58aa67ff2aac1b89ccc82"
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dependencies = [
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"futures 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
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]
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@ -1292,7 +1307,7 @@ dependencies = [
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"tokio-io 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-reactor 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-tcp 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-timer 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-timer 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio-udp 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
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"url 1.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
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]
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@ -1311,7 +1326,7 @@ dependencies = [
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"lru-cache 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
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"resolv-conf 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
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"smallvec 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
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"tokio 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
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"trust-dns-proto 0.4.0 (git+https://github.com/bluejekyll/trust-dns)",
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]
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@ -1586,7 +1601,7 @@ dependencies = [
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"checksum termion 1.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "689a3bdfaab439fd92bc87df5c4c78417d3cbe537487274e9b0b2dce76e92096"
|
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"checksum thread_local 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "279ef31c19ededf577bfd12dfae728040a21f635b06a24cd670ff510edd38963"
|
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"checksum time 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)" = "a15375f1df02096fb3317256ce2cee6a1f42fc84ea5ad5fc8c421cfe40c73098"
|
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"checksum tokio 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "7d00555353b013e170ed8bc4e13f648a317d1fd12157dbcae13f7013f6cf29f5"
|
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"checksum tokio 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "8ee337e5f4e501fc32966fec6fe0ca0cc1c237b0b1b14a335f8bfe3c5f06e286"
|
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"checksum tokio-connect 0.1.0 (git+https://github.com/carllerche/tokio-connect)" = "<none>"
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"checksum tokio-executor 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "8cac2a7883ff3567e9d66bb09100d09b33d90311feca0206c7ca034bc0c55113"
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"checksum tokio-fs 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "76766830bbf9a2d5bfb50c95350d56a2e79e2c80f675967fff448bc615899708"
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@ -1595,8 +1610,8 @@ dependencies = [
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"checksum tokio-rustls 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7abfd34d641c0cade850bd94bd0bbfa548b88adb2f08ae237a129144034ff9ae"
|
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"checksum tokio-signal 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6a5bf935a0151cc8899aa806ce6a425bdaec79ed4034de1a1e6bfa247e2def"
|
||||
"checksum tokio-tcp 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ec9b094851aadd2caf83ba3ad8e8c4ce65a42104f7b94d9e6550023f0407853f"
|
||||
"checksum tokio-threadpool 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "5783254b10c7c84a56f62c74766ef7e5b83d1f13053218c7cab8d3f2c826fa0e"
|
||||
"checksum tokio-timer 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "535fed0ccee189f3d48447587697ba3fd234b3dbbb091f0ec4613ddfec0a7c4c"
|
||||
"checksum tokio-threadpool 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "b3c3873a6d8d0b636e024e77b9a82eaab6739578a06189ecd0e731c7308fbc5d"
|
||||
"checksum tokio-timer 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)" = "028b94314065b90f026a21826cffd62a4e40a92cda3e5c069cc7b02e5945f5e9"
|
||||
"checksum tokio-udp 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "137bda266504893ac4774e0ec4c2108f7ccdbcb7ac8dced6305fe9e4e0b5041a"
|
||||
"checksum tower-balance 0.1.0 (git+https://github.com/tower-rs/tower)" = "<none>"
|
||||
"checksum tower-buffer 0.1.0 (git+https://github.com/tower-rs/tower)" = "<none>"
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|
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@ -1604,6 +1619,7 @@ dependencies = [
|
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"checksum tower-grpc 0.1.0 (git+https://github.com/tower-rs/tower-grpc)" = "<none>"
|
||||
"checksum tower-grpc-build 0.1.0 (git+https://github.com/tower-rs/tower-grpc)" = "<none>"
|
||||
"checksum tower-h2 0.1.0 (git+https://github.com/tower-rs/tower-h2)" = "<none>"
|
||||
"checksum tower-h2-balance 0.1.0 (git+https://github.com/tower-rs/tower-h2)" = "<none>"
|
||||
"checksum tower-in-flight-limit 0.1.0 (git+https://github.com/tower-rs/tower)" = "<none>"
|
||||
"checksum tower-reconnect 0.1.0 (git+https://github.com/tower-rs/tower)" = "<none>"
|
||||
"checksum tower-service 0.1.0 (git+https://github.com/tower-rs/tower)" = "<none>"
|
||||
|
|
|
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@ -27,30 +27,32 @@ hyper = "0.12"
|
|||
ipnet = "1.0"
|
||||
log = "0.4.1"
|
||||
indexmap = "1.0.0"
|
||||
prost = "0.3.0"
|
||||
prost-types = "0.3.0"
|
||||
rand = "0.4"
|
||||
|
||||
# for config parsing
|
||||
regex = "1.0.0"
|
||||
|
||||
tokio = "0.1.6"
|
||||
# networking
|
||||
tokio = "0.1.7"
|
||||
tokio-signal = "0.2"
|
||||
|
||||
prost = "0.3.0"
|
||||
prost-types = "0.3.0"
|
||||
|
||||
trust-dns-resolver = { default-features = false, git = "https://github.com/bluejekyll/trust-dns" }
|
||||
|
||||
tokio-connect = { git = "https://github.com/carllerche/tokio-connect" }
|
||||
tower-service = { git = "https://github.com/tower-rs/tower" }
|
||||
tower-balance = { git = "https://github.com/tower-rs/tower" }
|
||||
tower-buffer = { git = "https://github.com/tower-rs/tower" }
|
||||
tower-discover = { git = "https://github.com/tower-rs/tower" }
|
||||
tower-grpc = { git = "https://github.com/tower-rs/tower-grpc" }
|
||||
tower-h2 = { git = "https://github.com/tower-rs/tower-h2" }
|
||||
tower-reconnect = { git = "https://github.com/tower-rs/tower" }
|
||||
tower-in-flight-limit = { git = "https://github.com/tower-rs/tower" }
|
||||
tower-reconnect = { git = "https://github.com/tower-rs/tower" }
|
||||
tower-service = { git = "https://github.com/tower-rs/tower" }
|
||||
tower-util = { git = "https://github.com/tower-rs/tower" }
|
||||
tower-h2 = { git = "https://github.com/tower-rs/tower-h2" }
|
||||
tower-h2-balance = { git = "https://github.com/tower-rs/tower-h2" }
|
||||
tower-grpc = { git = "https://github.com/tower-rs/tower-grpc" }
|
||||
|
||||
# dns
|
||||
trust-dns-resolver = { default-features = false, git = "https://github.com/bluejekyll/trust-dns" }
|
||||
|
||||
# tls
|
||||
ring = "0.13.0-alpha4"
|
||||
webpki = "0.18.0-alpha4"
|
||||
rustls = "0.12.0"
|
||||
|
|
|
|||
|
|
@ -38,6 +38,7 @@ extern crate tower_buffer;
|
|||
extern crate tower_discover;
|
||||
extern crate tower_grpc;
|
||||
extern crate tower_h2;
|
||||
extern crate tower_h2_balance;
|
||||
extern crate tower_reconnect;
|
||||
extern crate tower_service;
|
||||
extern crate conduit_proxy_router;
|
||||
|
|
@ -81,7 +82,6 @@ mod transparency;
|
|||
mod transport;
|
||||
pub mod timeout;
|
||||
mod tower_fn; // TODO: move to tower-fn
|
||||
mod rng;
|
||||
|
||||
use bind::Bind;
|
||||
use connection::BoundPort;
|
||||
|
|
@ -356,12 +356,13 @@ fn serve<R, B, E, F, G>(
|
|||
) -> impl Future<Item = (), Error = io::Error> + Send + 'static
|
||||
where
|
||||
B: tower_h2::Body + Default + Send + 'static,
|
||||
B::Data: Send,
|
||||
<B::Data as ::bytes::IntoBuf>::Buf: Send,
|
||||
E: Error + Send + 'static,
|
||||
F: Error + Send + 'static,
|
||||
R: Recognize<
|
||||
Request = http::Request<HttpBody>,
|
||||
Response = http::Response<telemetry::sensor::http::ResponseBody<B>>,
|
||||
Response = http::Response<B>,
|
||||
Error = E,
|
||||
RouteError = F,
|
||||
>
|
||||
|
|
|
|||
|
|
@ -6,20 +6,21 @@ use std::sync::Arc;
|
|||
use http;
|
||||
use futures::{Async, Poll};
|
||||
use tower_service as tower;
|
||||
use tower_balance::{self, choose, load, Balance};
|
||||
use tower_balance::{choose, load, Balance};
|
||||
use tower_buffer::Buffer;
|
||||
use tower_discover::{Change, Discover};
|
||||
use tower_in_flight_limit::InFlightLimit;
|
||||
use tower_h2;
|
||||
use tower_h2_balance::{PendingUntilFirstData, PendingUntilFirstDataBody};
|
||||
use conduit_proxy_router::Recognize;
|
||||
|
||||
use bind::{self, Bind, Protocol};
|
||||
use control::destination::{self, Bind as BindTrait, Resolution};
|
||||
use ctx;
|
||||
use telemetry::sensor::http::{ResponseBody as SensorBody};
|
||||
use timeout::Timeout;
|
||||
use transparency::h1;
|
||||
use transparency::{h1, HttpBody};
|
||||
use transport::{DnsNameAndPort, Host, HostAndPort};
|
||||
use rng::LazyThreadRng;
|
||||
|
||||
type BindProtocol<B> = bind::BindProtocol<Arc<ctx::Proxy>, B>;
|
||||
|
||||
|
|
@ -31,6 +32,9 @@ pub struct Outbound<B> {
|
|||
|
||||
const MAX_IN_FLIGHT: usize = 10_000;
|
||||
|
||||
/// This default is used by Finagle.
|
||||
const DEFAULT_DECAY: Duration = Duration::from_secs(10);
|
||||
|
||||
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
|
||||
pub enum Destination {
|
||||
Hostname(DnsNameAndPort),
|
||||
|
|
@ -72,13 +76,16 @@ where
|
|||
<B::Data as ::bytes::IntoBuf>::Buf: Send,
|
||||
{
|
||||
type Request = http::Request<B>;
|
||||
type Response = bind::HttpResponse;
|
||||
type Response = http::Response<PendingUntilFirstDataBody<
|
||||
load::peak_ewma::Handle,
|
||||
SensorBody<HttpBody>,
|
||||
>>;
|
||||
type Error = <Self::Service as tower::Service>::Error;
|
||||
type Key = (Destination, Protocol);
|
||||
type RouteError = bind::BufferSpawnError;
|
||||
type Service = InFlightLimit<Timeout<Buffer<Balance<
|
||||
load::WithPendingRequests<Discovery<B>>,
|
||||
choose::PowerOfTwoChoices<LazyThreadRng>
|
||||
load::WithPeakEwma<Discovery<B>, PendingUntilFirstData>,
|
||||
choose::PowerOfTwoChoices,
|
||||
>>>>;
|
||||
|
||||
fn recognize(&self, req: &Self::Request) -> Option<Self::Key> {
|
||||
|
|
@ -147,12 +154,11 @@ where
|
|||
}
|
||||
};
|
||||
|
||||
let loaded = tower_balance::load::WithPendingRequests::new(resolve);
|
||||
|
||||
// We can't use `rand::thread_rng` here because the returned `Service`
|
||||
// needs to be `Send`, so instead, we use `LazyRng`, which calls
|
||||
// `rand::thread_rng()` when it is *used*.
|
||||
let balance = tower_balance::power_of_two_choices(loaded, LazyThreadRng);
|
||||
let balance = {
|
||||
let instrument = PendingUntilFirstData::default();
|
||||
let loaded = load::WithPeakEwma::new(resolve, DEFAULT_DECAY, instrument);
|
||||
Balance::p2c(loaded)
|
||||
};
|
||||
|
||||
let log = ::logging::proxy().client("out", Dst(dest.clone()))
|
||||
.with_protocol(protocol.clone());
|
||||
|
|
|
|||
|
|
@ -1,26 +0,0 @@
|
|||
use rand;
|
||||
|
||||
/// An empty type which implements `rand::Rng` by lazily getting the current
|
||||
/// `thread_rng` when its' called.
|
||||
///
|
||||
/// This can be used in cases where we need a type to be `Send`, but wish to
|
||||
/// use the thread-local RNG.
|
||||
#[derive(Copy, Clone, Debug, Default)]
|
||||
pub struct LazyThreadRng;
|
||||
|
||||
// ===== impl LazyRng =====
|
||||
|
||||
impl rand::Rng for LazyThreadRng {
|
||||
fn next_u32(&mut self) -> u32 {
|
||||
rand::thread_rng().next_u32()
|
||||
}
|
||||
|
||||
fn next_u64(&mut self) -> u64 {
|
||||
rand::thread_rng().next_u64()
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn fill_bytes(&mut self, bytes: &mut [u8]) {
|
||||
rand::thread_rng().fill_bytes(bytes)
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue