Motivation:
At the moment ChanneConfig.setAutoRead(false) only is guaranteer to not have an extra channelRead(...) triggered when used from within the channelRead(...) or channelReadComplete(...) method. This is not the correct behaviour as it should also work from other methods that are triggered from within the EventLoop. For example a valid use case is to have it called from within a ChannelFutureListener, which currently not work as expected.
Beside this there is another bug which is kind of related. Currently Channel.read() will not work as expected for OIO as we will stop try to read even if nothing could be read there after one read operation on the socket (when the SO_TIMEOUT kicks in).
Modifications:
Implement the logic the right way for the NIO/OIO/SCTP and native transport, specific to the transport implementation. Also correctly handle Channel.read() for OIO transport by trigger a new read if SO_TIMEOUT was catched.
Result:
It is now also possible to use ChannelConfig.setAutoRead(false) from other methods that are called from within the EventLoop and have direct effect.
Motivation:
At the moment we create a HashMap that holds the MembershipKeys for multicast with every NioDatagramChannel even when most people not need it at al
Modifications:
Lazy create the HashMap when needed.
Result:
Less memory usage and less object creation
Motivation:
When using System.getProperty(...) and various methods to get a ClassLoader it will fail when a SecurityManager is in place.
Modifications:
Use a priveled block if needed. This work is based in the PR #2353 done by @anilsaldhana .
Result:
Code works also when SecurityManager is present
Motivation:
Because we not null out the array entry in the SelectionKey[] which is produced by SelectedSelectionKeySet.flip() we may end up with a few SelectionKeyreferences still hanging around here even after the Channel was closed. As these entries may be present at the end of the SelectionKey[] which is never updated for a long time as not enough SelectionKeys are ready.
Modifications:
Once we access the SelectionKey out of the SelectionKey[] we directly null it out.
Result:
Reference can be GC'ed right away once the Channel was closed.
Motivation:
At the moment we do a Channel.isActive() check in every AbstractChannel.AbstractUnsafe.write(...) call which gives quite some overhead as shown in the profiler when you write fast enough. We can eliminate the check and do something more smart here.
Modifications:
Remove the isActive() check and just check if the ChannelOutboundBuffer was set to null before, which means the Channel was closed. The rest will be handled in flush0() anyway.
Result:
Less overhead when doing many write calls
Motivation:
At the moment an IllegalArgumentException will be thrown if a ChannelPromise is cancelled while propagate through the ChannelPipeline. This is not correct, we should just stop to propagate it as it is valid to cancel at any time.
Modifications:
Stop propagate the operation through the ChannelPipeline once a ChannelPromise is cancelled.
Result:
No more IllegalArgumentException when cancel a ChannelPromise while moving through the ChannelPipeline.
Motivation:
EventLoop overrides the next() method with the same signature of its
super class EventLoopGroup.
Modifications:
Remove the duplicate method declaration from the EventLoop interface.
Result:
Perhaps makes the API slightly more readable as there is one less
method.
Motivation:
At the moment we use the system-wide default selector provider for this invocation of the Java virtual machine when constructing a new NIO channel, which makes using an alternative SelectorProvider practically useless.
This change allows user specify his/her preferred SelectorProvider.
Modifications:
Add SelectorProvider as a param for current `private static *Channel newSocket` method of NioSocketChannel, NioServerSocketChannel and NioDatagramChannel.
Change default constructors of NioSocketChannel, NioServerSocketChannel and NioDatagramChannel to use DEFAULT_SELECTOR_PROVIDER when calling newSocket(SelectorProvider).
Add new constructors for NioSocketChannel, NioServerSocketChannel and NioDatagramChannel which allow user specify his/her preferred SelectorProvider.
Result:
Now users can specify his/her preferred SelectorProvider when constructing an NIO channel.
Motivation:
Some operating systems like Windows 7 uses a valid globally unique EUI-64 MAC address for a virtual device (e.g. 00:00:00:00:00:00:00:E0), and because it's usually longer than the legit MAC-48 address, we should not use the length of MAC address when two MAC addresses are of the same quality. Instead, we should compare the INET address of the NICs before comparing the length of the MAC addresses.
Modification:
Compare the length of MAC addresses as a last resort.
Result:
Correct MAC address detection in Windows with IPv6 enabled.
Motivation:
When there are two MAC addresses which are good enough, we can choose the one with better IP address rather than just choosing the first appeared one.
Modification:
Replace isBetterAddress() with compareAddresses() to make it return if both addresses are in the same preference level.
Add compareAddresses() which compare InetAddresses and use it when compareAddress(byte[], byte[]) returns 0 (same preference)
Result:
More correct primary MAC address detection
Motivation:
As reported in #2331, some query operations in NetworkInterface takes much longer time than we expected. For example, specifying -Djava.net.preferIPv4Stack=true option in Window increases the execution time by more than 4 times. Some Windows systems have more than 20 network interfaces, and this problem gets bigger as the number of unused (virtual) NICs increases.
Modification:
Use NetworkInterface.getInetAddresses() wherever possible.
Before iterating over all NICs reported by NetworkInterface, filter the NICs without proper InetAddresses. This reduces the number of candidates quite a lot.
NetUtil does not query hardware address of NIC in the first place but uses InetAddress.isLoopbackAddress().
Do not call unnecessary query operations on NetworkInterface. Just get hardware address and compare.
Result:
Significantly reduced class initialization time, which should fix#2331.
Motivation:
The current ascii table [1] showing the various states that a ChannelFuture
can be in, but the table is slightly "off" for the 'cause'.
Modifications:
- Updated the ascii table to display nicely.
Result:
Easier to read the states of a ChannelFuture.
[1] http://netty.io/5.0/api/io/netty/channel/ChannelFuture.html
Motivation:
Allow the user to create a NioServerSocketChannel from an existing ServerSocketChannel.
Modifications:
Add an extra constructor
Result:
Now the user is be able to create a NioServerSocketChannel from an existing ServerSocketChannel, like he can do with all the other Nio*Channel implemntations.
Motivation:
Ensure the user know the Channel must be closed to release resources like filehandles.
Modifications:
Add some extra javadoc.
Result:
More clear documentation
Motivation:
At the moment we use SocketChannel.open(), ServerSocketChannel.open() and DatagramSocketChannel.open(...) within the constructor of our
NIO channels. This introduces a bottleneck if you create a lot of connections as these calls delegate to SelectorProvider.provider() which
uses synchronized internal. This change removed the bottleneck.
Modifications:
Obtain a static instance of the SelectorProvider and use SelectorProvider.openSocketChannel(), SelectorProvider.openServerSocketChannel() and
SelectorProvider.openDatagramChannel(). This eliminates the bottleneck as SelectorProvider.provider() is not called on every channel creation.
Result:
Less conditions when create new channels.
Motivation:
Remove the synchronization bottleneck and so speed up things
Modifications:
Introduce a ThreadLocal cache that holds mappings between classes of ChannelHandlerAdapater implementations and the result of checking if the @Sharable annotation is present.
This way we only will need to do the real check one time and server the other calls via the cache. A ThreadLocal and WeakHashMap combo is used to implement the cache
as this way we can minimize the conditions while still be sure we not leak class instances in containers.
Result:
Less conditions during adding ChannelHandlerAdapter to the ChannelPipeline
This also does factor out some logic of ChannelOutboundBuffer. Mainly we not need nioBuffers() for many
transports and also not need to copy from heap to direct buffer. So this functionality was moved to
NioSocketChannelOutboundBuffer. Also introduce a EpollChannelOutboundBuffer which makes use of
memory addresses for all the writes to reduce GC pressure
- Inspired by #2214 by @normanmaurer
- Call setUncancellable() before performing an outbound operation
- Add safeSetSuccess/Failure() and use them wherever
- Related: #2163
- Add ResourceLeakHint to allow a user to provide a meaningful information about the leak when touching it
- DefaultChannelHandlerContext now implements ResourceLeakHint to tell where the message is going.
- Cleaner resource leak report by excluding noisy stack trace elements
