cb420a9ffc
Motivation:
The usage of Invocation level for JMH fixture methods (setup/teardown) inccurs in a significant impact in
in the benchmark time (see org.openjdk.jmh.annotations.Level documentation).
When the benchmark and the setup/teardown is too small (less than a milisecond) the Invocation level might saturate the system with
timestamp requests and iteration synchronizations which introduce artificial latency, throughput, and scalability bottlenecks.
In the HeadersBenchmark, all benchmarks take less than 100ns and the Invocation level setup offsets the measurement considerably.
As fixture methods is defined for the entire class, this overhead also impacts every single benchmark in this class, not only
the ones that use the emptyHttpHeaders object (cleaned in the setup).
The recommended fix patch here is to include the setup/teardown code in the benchmark where the object is used.
Modifications:
Include the setup/teardown code in the relevant benchmark methods.
Remove the setup/teardown method of Invocation level from the benchmark class.
Result:
We run all benchmarks from HeadersBenchmark 10 times with default parameter, we observe:
- Benchmarks that were not directly affected by the fix patch, improved execution time.
For instance, http2Remove with (exampleHeader = THREE) had its median reported as 2x faster than the original version.
- Benchmarks that had the setup code inserted (eg. http2AddAllFastest) did not suffer a significant punch in the execution time,
as the benchmarks are not dominated by the clear().
Environment:
Tests run on a Computational server with CPU: E5-1660-3.3GHZ (6 cores + HT), 64 GB RAM.
Netty Project
Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients.
Links
How to build
For the detailed information about building and developing Netty, please visit the developer guide. This page only gives very basic information.
You require the following to build Netty:
- Latest stable Oracle JDK 7
- Latest stable Apache Maven
- If you are on Linux, you need additional development packages installed on your system, because you'll build the native transport.
Note that this is build-time requirement. JDK 5 (for 3.x) or 6 (for 4.0+) is enough to run your Netty-based application.
Branches to look
Development of all versions takes place in each branch whose name is identical to <majorVersion>.<minorVersion>. For example, the development of 3.9 and 4.0 resides in the branch '3.9' and the branch '4.0' respectively.
Usage with JDK 9
Netty can be used in modular JDK9 applications as a collection of automatic modules. The module names follow the reverse-DNS style, and are derived from subproject names rather than root packages due to historical reasons. They are listed below:
io.netty.allio.netty.bufferio.netty.codecio.netty.codec.dnsio.netty.codec.haproxyio.netty.codec.httpio.netty.codec.http2io.netty.codec.memcacheio.netty.codec.mqttio.netty.codec.redisio.netty.codec.smtpio.netty.codec.socksio.netty.codec.stompio.netty.codec.xmlio.netty.commonio.netty.handlerio.netty.handler.proxyio.netty.resolverio.netty.resolver.dnsio.netty.transportio.netty.transport.epoll(nativeomitted - reserved keyword in Java)io.netty.transport.kqueue(nativeomitted - reserved keyword in Java)io.netty.transport.unix.common(nativeomitted - reserved keyword in Java)io.netty.transport.rxtxio.netty.transport.sctpio.netty.transport.udt
Automatic modules do not provide any means to declare dependencies, so you need to list each used module separately
in your module-info file.