abdcf102da
Motivation: We have found out that ByteBufUtil.indexOf can be inefficient for substring search on ByteBuf, both in terms of algorithm complexity (worst case O(needle.readableBytes * haystack.readableBytes)), and in constant factor (esp. on Composite buffers). With implementation of more performant search algorithms we have seen improvements on the order of magnitude. Modifications: This change introduces three search algorithms: 1. Knuth Morris Pratt - classical textbook algorithm, a good default choice. 2. Bit mask based algorithm - stable performance on any input, but limited to maximum search substring (the needle) length of 64 bytes. 3. Aho–Corasick - worse performance and higher memory consumption than [1] and [2], but it supports multiple substring (the needles) search simultaneously, by inspecting every byte of the haystack only once. Each algorithm processes every byte of underlying buffer only once, they are implemented as ByteProcessor. Result: Efficient search algorithms with linear time complexity available in Netty (I will share benchmark results in a comment on a PR).
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.