Merge pull request #173 from influxdata/dom/async-flush

perf: async flushing & buffering + lock contention

Author: domodwyer

Cargo.toml

@@ -33,7 +33,7 @@ rustls = { version = "0.20", optional = true }
 snap = { version = "1", optional = true }
 thiserror = "1.0"
 time = "0.3"
-tokio = { version = "1.14", default-features = false, features = ["io-util", "net", "rt", "sync", "time", "macros"] }
+tokio = { version = "1.19", default-features = false, features = ["io-util", "net", "rt", "sync", "time", "macros"] }
 tokio-rustls = { version = "0.23", optional = true }
 tracing = "0.1"
 zstd = { version = "0.10", optional = true }