Motivation:
The HttpObjectDecoder is on the hot code path for the http codec. There are a few hot methods which can be modified to improve performance.
Modifications:
- Modify AppendableCharSequence to provide unsafe methods which don't need to re-check bounds for every call.
- Update HttpObjectDecoder methods to take advantage of new AppendableCharSequence methods.
Result:
Peformance boost for decoding http objects.
Motivation:
We don't decrease acquired channel count in FixedChannelPool when timeout occurs by AcquireTimeoutAction.NEW and eventually fails.
Modifications:
Set AcquireTask.acquired=true to call decrementAndRunTaskQueue when timeout action fails.
Result:
Acquired channel count decreases correctly.
Motivation:
We pass-through non ByteBuf when SslHandler.write(...) is called which can lead to have unencrypted data to be send (like for example if a FileRegion is written).
Modifications:
- Fail ChannelPromise with UnsupportedMessageException if a non ByteBuf is written.
Result:
Only allow ByteBuf to be written when using SslHandler.
Motivation:
Remove RC4 from default ciphers as it is not known as secure anymore.
Modifications:
Remove RC4
Result:
Not use an insecure cipher as default.
Motivation:
We missed to correctly count acquired channels in FixedChannelPool which could produce an assert error.
Modifications:
Only try to decrement acquired count if the channel was really acuired.
Result:
No more assert error possible.
Motivation:
We missed to register for EPOLLRDHUP events when construct the EpollSocketChannel from an existing FileDescriptor. This could cause to miss connection-resets.
Modifications:
Add Native.EPOLLRDHUP to the events we are interested in.
Result:
Connection-resets are detected correctly.
Motivation:
Prior we used a purge task that would remove previous canceled scheduled tasks from the internal queue. This could introduce some delay and so use a lot of memory even if the task itself is already canceled.
Modifications:
Schedule removal of task from queue via EventLoop if cancel operation is not done in the EventLoop Thread or just remove directly if the Thread that cancels the scheduled task is in the EventLoop.
Result:
Faster possibility to GC a canceled ScheduledFutureTask.
Motivation:
If the Channel is already closed when the PendingWriteQueue is created it will generate a NPE when add or remove is called later.
Modifications:
Add null checks to guard against NPE.
Result:
No more NPE possible.
Motivation:
In 4.1 and master branch we allow to construct an EmbeddedChannel without ChannelHandlers, we should do the same in 4.0.
Modifications:
Backport behavoir.
Result:
It's now possible to construct an EmbeddedChannel without any ChannelHandler
Motivation:
WebSocketServerHandshakerFactory.sendUnsupportedVersionResponse does not
send a LastHttpContent, nor does it flush, and it doesn't send a content
length.
Modifications:
Changed sendUnsupportedVersionResponse to send FullHttpResponse, to
writeAndFlush, and to set a content length of 0. Also added a test for
this method.
Result:
Upstream handlers will be able to determine the end of the response, the
response will actually get written to the client, and the client will be
able to determine the end of the response.
Motivation:
When using an EmbeddedChannel often it either does inbound or outbound processing which means we only often need one queue.
Modifications:
Lazy init the inbound and outbound message queues.
Result:
Less memory usage.
Motivation:
When we detect a BUFFER_OVERFLOW we should just forward the already produced data and allocate a new buffer and NOT do any extra memory copies while trying to expand the buffer.
Modifications:
When a BUFFER_OVERFLOW is returned and some data was produced just fire this data through the pipeline and allocate a new buffer to read again.
Result:
Less memorycopies and so better performance.
Motivation:
A SSL_read is needed to ensure the bio buffer is flushed, for this we did a priming read. This can be removed in many cases. Also ensure we always fill as much as possible in the destination buffers.
Modifications:
- Only do priming read if capacity of all dsts buffers is zero
- Always produce as must data as possible in the dsts buffers.
Result:
Faster code.
Motivation:
Previous we called BIO_write until either everything was written into it or it returned an error, which meant that the buffer is full. This then needed a ERR_clear_error() call which is expensive.
Modifications:
Break out of writing loop once we detect that not everything was written and so the buffer is full.
Result:
Less overhead when writing more data then the internal buffer can take.
Motivation:
When BIO_write is called with an empty buffer it will return 0 for which we call ERR_clear_error(). This is not neccessary as we should just skip these buffers. This eliminates a lot of overhead.
Modifications:
Skip empty src buffers when call unwrap(...).
Result:
Less overhead for unwrap(...) when called with empty buffers.
Motivation:
If a user tries to access various informations on the OpenSslSession after the SSLEngine was closed it will not work if these were not accessed before as we lazy init most of them.
Modifications:
Directly populate the whole OpenSslSession once the handshake is complete and before the user is notified about it.
Result:
OpenSslSession informations are avaible until it is GC'ed.
Motivation:
At the moment we directly closed the Channel when an exception accoured durring initChannel(...) without giving the user any way to do extra or special handling.
Modifications:
Handle the exception in exceptionCaught(...) of the ChannelInitializer which will by default log and close the Channel. This way the user can override this.
Result:
More felixible handling of exceptions.
Motivation:
Currently in EmbeddedChannel we add the ChannelHandlers before the Channel is registered which leads to have the handlerAdded(...) callback
be called from outside the EventLoop and also prevent the user to obtain a reference to the EventLoop in the callback itself.
Modifications:
Delay adding ChannelHandlers until EmbeddedChannel is registered.
Result:
Correctly call handlerAdded(...) after EmbeddedChannel is registered.
Motivation:
If you set a ChannelHandler via ServerBootstrap.handler(...) it is added to the ChannelPipeline before the Channel is registered. This will lead to and IllegalStateException if a user tries to access the EventLoop in the ChannelHandler.handlerAdded(...) method.
Modifications:
Delay the adding of the ChannelHandler until the Channel was registered.
Result:
No more IllegalStateException.
Motivation:
As we modify the position of the passed in ByteBuffer's this methods are not thread-safe.
Modifications:
Duplicate the input ByteBuffers before copy the content to byte[].
Result:
Unpooled.copiedBuffer(ByteBuffer) and copiedBuffer(ByteBuffer...) is now thread-safe.
Motivation:
The javadoc of ByteBuf contained some out-dated code.
Modifications:
Update code example in javadoc to use netty 4+ API
Result:
Correct javadocs
Motivation:
FixedCompositeByteBuf does not properly implement a number of methods for
copying its content to direct buffers and output streams
Modifications:
Replace improper use of capacity() with readableBytes() when computing offesets during writes
Result:
Copying works correctly
This implementation does not produce as much GC pressure as CompositeByteBuf and so is prefered,
for writing an array of ByteBufs. Be aware that FixedCompositeByteBuf is readonly.
When using this in a project that make heavy use of CompositeByteBuf for writes we was able to cut
down allocation to a half.
Motivation:
Sometimes it is useful to detect if a ByteBuf contains a HAProxy header, for example if you want to write something like the PortUnification example.
Modifications:
- Add ProtocolDetectionResult which can be used as a return type for detecting different protocol.
- Add new method which allows to detect HA Proxy messages.
Result:
Easier to detect protocol.
Motivation:
We used ERR_get_error() to detect errors and missed to handle different errors. Also we missed to clear the error queue for a thread before invoke SSL operations,
this could lead to detecting errors on different OpenSslEngines then the one in which the error actual happened.
Modifications:
Explicit handle errors via SSL.get_error and clear the error code before SSL operations.
Result:
Correctly handle errors and no false-positives in different OpenSslEngines then the one which detected an error.
Motivation:
Only one of the three FixedChannelPool constructors checks for the constructor
arguments. Therfore it was possible to create a pool with zero maxConnections.
This change chains all constructors together, so that the last one
in the chain always checks the validity of the arguments, regardless of the
constructor used.
Result:
It is no longer possible to create a FixedChannelPool instance with invalid
maxConnections or maxPendingAcquires parameters.
Motivation:
At the moment we use 1 * cores as default mimimum for pool arenas. This can easily lead to conditions as we use 2 * cores as default for EventLoop's when using NIO or EPOLL. If we choose a smaller number we will run into hotspots as allocation and deallocation needs to be synchronized on the PoolArena.
Modifications:
Change the default number of arenas to 2 * cores.
Result:
Less conditions when using the default settings.
Motivation:
According to the javadocs of SSLSession.getPeerPrincipal should be returning the identity of the peer, while we return the identity of the issuer.
Modifications:
Return the correct indentity.
Result:
Behavior match the documentation.
Motivation:
FixedChannelPool should enforce a number of maximal used channels, but due a bug we fail to correctly enforce this.
Modifications:
Change check to correctly only acquire channel if we not hit the limit yet.
Result:
Correct limiting.
Motiviation:
To be consistent with changes in 4.1 and master. This is a new method and should not impact compatibility.
Modifications:
- ChannelOutboundBuffer method bytesBeforeUnWritable -> bytesBeforeUnwritable
Result:
Consistent interface for 4.0, 4.1, and master.
Motivation:
Dumping the content of a ByteBuf in a hex format is very useful.
Modifications:
Move code into ByteBufUtil so its easy to reuse.
Result:
Easy to reuse dumping code.
Motivation:
It's useful to be able to be notified once all Channels that are part of the ChannelGroup are notified. This can for example be useful if you want to do a graceful shutdown.
Modifications:
- Add ChannelGroup.newCloseFuture(...) which will be notified once all Channels are notified that are part of the ChannelGroup at the time of calling.
Result:
Easier to be notified once all Channels within a ChannelGroup are closed.
Motiviation:
There are currently no accessors which provide visbility into how many bytes must be written in order for a writability change to occur. This feature would be useful for codecs which intent to control how many bytes are queued at any given time.
Modifications:
- add bytesBeforeUnWritable() which will give the number of bytes before the buffer (and associated channel) transitions to not writable
- add bytesBeforeWritable() which will give the number of bytes that must be drained from the queue until the channel becomes writable.
Result:
More visibility into writability for the ChannelOutboundBuffer.
Motivation:
Due a copy and paste error we incorrectly skipped the first cert in the keyCertChainFile when using OpenSslClientContext.
Modifications:
Correctly not skip the first cert.
Result:
The certificate chain is correctly setup when using OpenSslClientContext.
Motivation:
We need to ensure we never allow to have null values set on headers, otherwise we will see a NPE during encoding them.
Modifications:
Add null check.
Result:
Correctly throw exception when a null header value is added/set
Motivation:
If the handlerAdded(...) callback was not called, the checkDeadLock() of the handshakeFuture will produce an IllegalStateException.
This was first reported at https://github.com/impossibl/pgjdbc-ng/issues/168 .
Modifications:
Pass deadlock check if ctx is null
Result:
No more race and so IllegalStateException.
Motivation:
Some glibc/kernel versions will trigger an EPOLLERR event to notify
about failed connect and not an EPOLLOUT. Also EPOLLERR may be triggered
when a connection is broke.
Modification:
React on EPOLLERR like if an EPOLLOUT / EPOLLIN was received, this will work in
all cases as we handle errors in EPOLLOUT / EPOLLIN anyway.
Result:
Correctly detect errors.
Motivation:
SpdyOrHttpChooser and Http2OrHttpChooser duplicate fair amount code with each other.
Modification:
- Replace SpdyOrHttpChooser and Http2OrHttpChooser with ApplicationProtocolNegotiationHandler
- Add ApplicationProtocolNames to define the known application-level protocol names
- Deprecate SpdyOrHttpChooser
Result:
- Less code duplication
- A user can perform dynamic pipeline configuration that follows ALPN/NPN for any protocols.
Related: #3641 and #3813
Motivation:
When setting up an HTTP/1 or HTTP/2 (or SPDY) pipeline, a user usually
ends up with adding arbitrary set of handlers.
Http2OrHttpChooser and SpdyOrHttpChooser have two abstract methods
(create*Handler()) that expect a user to return a single handler, and
also have add*Handlers() methods that add the handler returned by
create*Handler() to the pipeline as well as the pre-defined set of
handlers.
The problem is, some users (read: I) don't need all of them or the
user wants to add more than one handler. For example, take a look at
io.netty.example.http2.tiles.Http2OrHttpHandler, which works around
this issue by overriding addHttp2Handlers() and making
createHttp2RequestHandler() a no-op.
Modifications:
- Replace add*Handlers() and create*Handler() with configure*()
- Rename getProtocol() to selectProtocol() to make what it does clear
- Provide the default implementation of selectProtocol()
- Remove SelectedProtocol.UNKNOWN and use null instead, because
'UNKNOWN' is not a protocol
- Proper exception handling in the *OrHttpChooser so that the
exception is logged and the connection is closed when failed to
select a protocol
- Make SpdyClient example always use SSL. It was always using SSL
anyway.
- Implement SslHandshakeCompletionEvent.toString() for debuggability
- Remove an orphaned class: JettyNpnSslSession
- Add SslHandler.applicationProtocol() to get the name of the
application protocol
- SSLSession.getProtocol() now returns transport-layer protocol name
only, so that it conforms to its contract.
Result:
- *OrHttpChooser have better API.
- *OrHttpChooser handle protocol selection failure properly.
- SSLSession.getProtocol() now conforms to its contract.
- SpdyClient example works with SpdyServer example out of the box
Motivation:
For advanced use-cases it an be helpful to be able to directly access the SSL_CTX and SSL pointers of the underlying openssl objects. This for example allows to register custom C callbacks.
Modifications:
- Expose the SSL_CTX and SSL pointers
- Cleanup the shutdown code
Result:
It's now possible to obtain the c pointes and set native callbacks.
