Jakob Buchgraber 8c18a0d355 netty: use custom http2 headers for decoding. ... The DefaultHttp2Headers class is a general-purpose Http2Headers implementation and provides much more functionality than we need in gRPC. In gRPC, when reading headers off the wire, we only inspect a handful of them, before converting to Metadata. This commit introduces a Http2Headers implementation that aims for insertion efficiency, a low memory footprint and fast conversion to Metadata. - Header names and values are stored in plain byte[]. - Insertion is O(1), while lookup is now O(n). - Binary header values are base64 decoded as they are inserted. - The byte[][] returned by namesAndValues() can directly be used to construct a new Metadata object. - For HTTP/2 request headers, the pseudo headers are no longer carried over to Metadata. A microbenchmark aiming to replicate the usage of Http2Headers in NettyClientHandler and NettyServerHandler shows decent throughput gains when compared to DefaultHttp2Headers. Benchmark Mode Cnt Score Error Units InboundHeadersBenchmark.defaultHeaders_clientHandler avgt 10 283.830 ± 4.063 ns/op InboundHeadersBenchmark.defaultHeaders_serverHandler avgt 10 1179.975 ± 21.810 ns/op InboundHeadersBenchmark.grpcHeaders_clientHandler avgt 10 190.108 ± 3.510 ns/op InboundHeadersBenchmark.grpcHeaders_serverHandler avgt 10 561.426 ± 9.079 ns/op Additionally, the memory footprint is reduced by more than 50%! gRPC Request Headers: 864 bytes Netty Request Headers: 1728 bytes gRPC Response Headers: 216 bytes Netty Response Headers: 528 bytes Furthermore, this change does most of the gRPC groundwork necessary to be able to cache higher ordered objects in HPACK's dynamic table, as discussed in [1]. [1] https://github.com/grpc/grpc-java/issues/2217		2016-09-09 23:15:18 +02:00
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src	netty: use custom http2 headers for decoding.	2016-09-09 23:15:18 +02:00
build.gradle	core: split Context into a separate grpc-context artifact.	2016-09-02 13:18:35 -07:00