Related: #3212
Motivation:
When SslHandler and ChunkedWriteHandler exists in a pipeline together,
it is possible that ChunkedWriteHandler.channelWritabilityChanged()
invokes SslHandler.flush() and vice versa. Because they can feed each
other (i.e. ChunkedWriteHandler.channelWritabilityChanged() ->
SslHandler.flush() -> ChunkedWriteHandler.channelWritabilityChanged() ->
..), they can fall into an inconsistent state due to reentrance (e.g.
bad MAC record at the remote peer due to incorrect ordering.)
Modifications:
- Trigger channelWritabilityChanged() using EventLoop.execute() when
there's a chance where channelWritabilityChanged() can cause a
reentrance issue
- Fix test failures caused by the modification
Result:
Fix the handler reentrance issues related with a
channelWritabilityChanged() event
Related: #3219
Motivation:
ChunkedWriteHandler.flush() does not call ctx.flush() when channel is
not writable. This can be a problem when other handler / non-Netty
thread writes messages simultaneously, because
ChunkedWriteHandler.flush() might have no chance to observe
channel.isWritable() returns true and thus the channel is never flushed.
Modifications:
- Ensure that ChunkedWriteHandler.flush() calls ctx.flush() at least
once.
Result:
A stall connection issue, that occurs when certain combination of
handlers exist in a pipeline, has been fixed. (e.g. SslHandler and
ChunkedWriteHandler)
Motivations:
The chunkSize might be oversized after comparison (size being > of int
capacity) if file size is bigger than an integer.
Modifications:
Change it to long.
Result:
There is no more int oversized.
Same fix for 4.1 and Master
Related: #3212
Motivation:
PendingWriteQueue.recycle() updates its data structure after triggering
a channelWritabilityChanged() event. It causes a rare corruption such as
double free when channelWritabilityChanged() method accesses the
PendingWriteQueue.
Modifications:
Update the state of PendingWriteQueue before triggering an event.
Result:
Fix a rare double-free problem
Related: #3190
Motivation:
When an outbound handler method raises an exception, its promise is
marked as failed. If the promise is done already, the exception is
logged.
When the promise is void, exceptionCaught() must be triggered to notify
a user. However, AbstractChannelHandlerContext simply swallows it.
Modifications:
Do not swallow an exception when the promise is void.
Result:
A user who uses a void promise for an outbound operation will be
notified on failure.
Related: #3189
Motivation:
OIO transport implementations block for at most 1 second to wait for
additional messages (or accepted connections).
However, because AbstractOioMessageChannel defers the channelRead()
events for the messages read so far until there's nothing to read up to
maxMessagesPerRead, any read operation will be followed by a 1-second
delay.
Modifications:
Fire channelRead() events as soon as doRead() returns so that there is
no 1 second delay between the actual read and the channelRead() event.
Result:
No more weird 1-second delay
Related: #3166
Motivation:
When the recyclable object created at one thread is returned at the
other thread, it is stored in a WeakOrderedQueue.
The objects stored in the WeakOrderedQueue is added back to the stack by
WeakOrderedQueue.transfer() when the owner thread ran out of recyclable
objects.
However, WeakOrderedQueue.transfer() does not have any mechanism that
prevents the stack from growing beyond its maximum capacity.
Modifications:
- Make WeakOrderedQueue.transfer() increase the capacity of the stack
only up to its maximum
- Add tests for the cases where the recyclable object is returned at the
non-owner thread
- Fix a bug where Stack.scavengeSome() does not scavenge the objects
when it's the first time it ran out of objects and thus its cursor is
null.
- Overall clean-up of scavengeSome() and transfer()
Result:
The capacity of Stack never increases beyond its maximum.
Motivation:
io.netty.util.internal.PlatformDependent.isRoot() depends on the IS_ROOT field which is filled in during class initialization. This spawns processes and consumes resources, which are not generally necessary to the complete functioning of that class.
Modifications:
This switches the class to use lazy initialization this field inside of the isRoot() method using double-checked locking (http://en.wikipedia.org/wiki/Double-checked_locking).
Result:
The first call to isRoot() will be slightly slower, at a tradeoff that class loading is faster, uses fewer resources and platform errors are avoided unless necessary.
Related: #3156
Motivation:
Let's say we have a channel with the following pipeline configuration:
HEAD --> [E1] H1 --> [E2] H2 --> TAIL
when the channel is deregistered, the channelUnregistered() methods of
H1 and H2 will be invoked from the executor thread of E1 and E2
respectively. To ensure that the channelUnregistered() methods are
invoked from the correct thread, new one-time tasks will be created
accordingly and be scheduled via Executor.execute(Runnable).
As soon as the one-time tasks are scheduled,
DefaultChannelPipeline.fireChannelUnregistered() will start to remove
all handlers from the pipeline via teardownAll(). This process is
performed in reversed order of event propagation. i.e. H2 is removed
first, and then H1 is removed.
If the channelUnregistered() event has been passed to H2 before H2 is
removed, a user does not see any problem.
If H2 has been removed before channelUnregistered() event is passed to
H2, a user will often see the following confusing warning message:
An exceptionCaught() event was fired, and it reached at the tail of
the pipeline. It usually means the last handler in the pipeline did
not handle the exception.
Modifications:
To ensure that the handlers are removed *after* all events are
propagated, traverse the pipeline in ascending order before performing
the actual removal.
Result:
A user does not get the confusing warning message anymore.
- Parameterize DomainNameMapping to make it useful for other use cases
than just mapping to SslContext
- Move DomainNameMapping to io.netty.util
- Clean-up the API documentation
- Make SniHandler.hostname and sslContext volatile because they can be
accessed by non-I/O threads
Motivation:
We use 3 (!) libraries to build mock objects - easymock, mockito, jmock.
Mockito and jMock pulls in the different versions of Hamcrest, and it
conflicts with the version pulled by jUnit.
Modifications:
- Replace mockito-all with mockito-core to avoid pulling in outdated
jUnit and Hamcrest
- Exclude junit-dep when pulling in jmock-junit4, because it pulls an
outdated Hamcrest version
- Pull in the hamcrest-library version used by jUnit explicitly
Result:
No more dependency hell that results in NoSuchMethodError during the
tests
Motivation:
When we need to host multiple server name with a single IP, it requires
the server to support Server Name Indication extension to serve clients
with proper certificate. So the SniHandler will host multiple
SslContext(s) and append SslHandler for requested hostname.
Modification:
* Added SniHandler to host multiple certifications in a single server
* Test case
Result:
User could use SniHandler to host multiple certifcates at a time.
It's server-side only.
Motivation:
8fbc513 introduced stray warnings in callsites of
PromiseAggregator#add and PromiseNotifier#(...).
Modifications:
This commit adds the @SafeVarargs annotation to PromiseAggregator#add
and PromiseNotifier#(...). As Netty is built with JDK7, this is a
recognized annotation and should not affect runtime VM versions 1.5 and
1.6.
Result:
Building Netty with JDK7 will no longer produce warnings in the
callsites mentioned above.
Motivation:
AbstractUnsafe considers two possibilities during channel registration. First,
the channel may be an outgoing connection, in which case it will be registered
before becoming active. Second, the channel may be an incoming connection in,
which case the channel will already be active when it is registered. To handle
the second case, AbstractUnsafe checks if the channel is active after
registration and calls ChannelPipeline.fireChannelActive() if so. However, if
an active channel is deregistered and then re-registered this logic causes a
second fireChannelActive() to be invoked. This is unexpected; it is reasonable
for handlers to assume that this method will only be invoked once per channel.
Modifications:
This change introduces a flag into AbstractUnsafe to recognize if this is the
first or a subsequent registration. ChannelPipeline.fireChannelActive() is only
possible for the first registration.
Result:
ChannelPipeline.fireChannelActive() is only called once.
Motivation:
JdkSslContext used SSL_RSA_WITH_DES_CBC_SHA in its cipher suite list.
OpenSslServerContext used DES-CBC3-SHA in the same place in its cipher suite
list, which is equivalent to SSL_RSA_WITH_3DES_EDE_CBC_SHA.
This means the lists were out of sync. Furthermore, using
SSL_RSA_WITH_DES_CBC_SHA is not desirable as it uses DES, a weak cipher. Triple
DES should be used instead.
Modifications:
Replace SSL_RSA_WITH_DES_CBC_SHA with SSL_RSA_WITH_3DES_EDE_CBC_SHA in
JdkSslContext.
Result:
The JdkSslContext and OpenSslServerContext cipher suite lists are now in sync.
Triple DES is used instead of DES, which is stronger.
Motivation:
RC4 is not a recommended cipher suite anymore, as the recent research
reveals, such as:
- http://www.isg.rhul.ac.uk/tls/
Modifications:
- Remove most RC4 cipher suites from the default cipher suites
- For backward compatibility, leave RC4-SHA, while de-prioritizing it
Result:
Potentially safer default
Motivation:
Although the new IntObjectMap.values() that returns Collection is
useful, the removed values(Class<V>) that returns an array is also
useful. It's also good for backward compatibility.
Modifications:
- Add IntObjectMap.values(Class<V>) back
- Miscellaneous improvements
- Cache the collection returned by IntObjectHashMap.values()
- Inspector warnings
- Update the IntObjectHashMapTest to test both values()
Result:
- Backward compatibility
- Potential performance improvement of values()
Related: #3122
Motivation:
The HttpStaticFileServer example writes the LastHttpContent twice at the
end of the transfer. HttpChunkedInput already produces a
LastHttpContent at the end of the stream, so there's no reason to write
another.
Modifications:
Do not write LastHttpContent in HttpStaticFileServerHandler when
HttpChunkedInput is used to transfer a file.
Result:
HttpStaticFileServer does not violates the protocol anymore.
Motivation:
The mentioned commit contains a bug fix and an improvement in
IntObjectHashMap that requires backporting.
Modifications:
Update IntObjectMap, IntObjectHashMap, and IntObjectHashMapTest
Result:
Easier to backport HTTP/2 and other changes in master in the future
Motivation:
When running the examples using the provided run-examples.sh script the
log level is 'info' level. It can be handy to be able to configure a
different level, for example 'debug', while learning and trying out the
the examples.
Modifications:
Added a dependency to logback-classic to the examples pom.xml, and also
added a logback configuration file. The log level can be configured by
setting the 'logLevel' system property, and if that property is not set
the default will be 'info' level.
The run-examples.sh was updated to show an example of using the system
property to set the log level to 'debug'
Result:
It is now possible to turn on debug logging by settnig a system property
on the command line.
Motivation:
Found performance issues via FindBugs and PMD.
Modifications:
- Removed unnecessary boxing/unboxing operations in DefaultTextHeaders.convertToInt(CharSequence) and DefaultTextHeaders.convertToLong(CharSequence). A boxed primitive is created from a string, just to extract the unboxed primitive value.
- Added a static modifier for DefaultHttp2Connection.ParentChangedEvent class. This class is an inner class, but does not use its embedded reference to the object which created it. This reference makes the instances of the class larger, and may keep the reference to the creator object alive longer than necessary.
- Added a static compiled Pattern to avoid compile it each time it is used when we need to replace some part of authority.
- Improved using of StringBuilders.
Result:
Performance improvements.
Motivation:
Currently, we only test our ZlibEncoders against our ZlibDecoders. It is
convenient to write such tests, but it does not necessarily guarantee
their correctness. For example, both encoder and decoder might be faulty
even if the tests pass.
Modifications:
Add another test that makes sure that our GZIP encoder generates the
GZIP trailer, using the fact that GZIPInputStream raises an EOFException
when GZIP trailer is missing.
Result:
More coverage for GZIP compression
Motivation:
The SPDY/3.1 spec does not adequate describe how to push resources
from the server. This was solidified in the HTTP/2 drafts by dividing
the push into two frames, a PushPromise containing the request,
followed by a Headers frame containing the response.
Modifications:
This commit modifies the SpdyHttpDecoder to support pushed resources
that are divided into multiple frames. The decoder will accept a
pushed SpdySynStreamFrame containing the request headers, followed by
a SpdyHeadersFrame containing the response headers.
Result:
The SpdyHttpDecoder will create an HttpRequest object followed by an
HttpResponse object when receiving pushed resources.
Motivation:
RFC 2616, 4.3 Message Body states that:
All 1xx (informational), 204 (no content), and 304 (not modified) responses MUST NOT include a
message-body. All other responses do include a message-body, although it MAY be of zero length.
Modifications:
HttpContentEncoder was previously modified to cater for HTTP 100 responses. This check is enhanced to
include HTTP 204 and 304 responses.
Result:
Empty response bodies will not be modified to include the compression footer. This footer messed with Chrome's
response parsing leading to "hanging" requests.
Motivation:
HttpObjectDecoder extended ReplayDecoder which is slightly slower then ByteToMessageDecoder.
Modifications:
- Changed super class of HttpObjectDecoder from ReplayDecoder to ByteToMessageDecoder.
- Rewrote decode() method of HttpObjectDecoder to use proper state machine.
- Changed private methods HeaderParser.parse(ByteBuf), readHeaders(ByteBuf) and readTrailingHeaders(ByteBuf), skipControlCharacters(ByteBuf) to consider available bytes.
- Set HeaderParser and LineParser as static inner classes.
- Replaced not safe actualReadableBytes() with buffer.readableBytes().
Result:
Improved performance of HttpObjectDecoder by approximately 177%.
Motivation:
NetUtil.isValidIpV6Address() handles the interface name in IPv6 address
incorrectly. For example, it returns false for the following addresses:
- ::1%lo
- ::1%_%_in_name_
Modifications:
- Strip the square brackets before validation for simplicity
- Strip the part after the percent sign completely before validation for
simplicity
- Simplify and reformat NetUtilTest
Result:
- The interface names in IPv6 addresses are handled correctly.
- NetUtilTest is cleaner
Motivation:
ChannelPromiseAggregator and ChannelPromiseNotifiers only allow
consumers to work with Channels as the result type. Generic versions
of these classes allow consumers to aggregate or broadcast the results
of an asynchronous execution with other result types.
Modifications:
Add PromiseAggregator and PromiseNotifier. Add unit tests for both.
Remove code in ChannelPromiseAggregator and ChannelPromiseNotifier and
modify them to extend the new base classes.
Result:
Consumers can now aggregate or broadcast the results of an asynchronous
execution with results types other than Channel.
Motiviation:
The HttpContentEncoder does not account for a EmptyLastHttpContent being provided as input. This is useful in situations where the client is unable to determine if the current content chunk is the last content chunk (i.e. a proxy forwarding content when transfer encoding is chunked).
Modifications:
- HttpContentEncoder should not attempt to compress empty HttpContent objects
Result:
HttpContentEncoder supports a EmptyLastHttpContent to terminate the response.
Motivation:
When ALPN/NPN is disabled, a user has to instantiate a new
ApplicationProtocolConfig with meaningless parameters.
Modifications:
- Add ApplicationProtocolConfig.DISABLED, the singleton instance
- Reject the constructor calls with Protocol.NONE, which doesn't make
much sense because a user should use DISABLED instead.
Result:
More user-friendly API when ALPN/NPN is not needed by a user.
Motivation:
Previous backport removed the old methods and constructors. They should
not be removed in 4.x but just deprecated in favor of the new methods
and constructors.
Modifications:
Add back the removed methods and constructors in SslContext and its
subtypes for backward compatibility.
Result:
Backward compatibility issues fixed.
Motivation:
Improvements were made on the main line to support ALPN and mutual
authentication for TLS. These should be backported.
Modifications:
- Backport commits from the master branch
- f8af84d599
- e74c8edba3
Result:
Support for ALPN and mutual authentication.
Motivation:
The SslHandler currently forces the use of a direct buffer for the input to the SSLEngine.wrap(..) operation. This allocation may not always be desired and should be conditionally done.
Modifications:
- Use the pre-existing wantsDirectBuffer variable as the condition to do the conversion.
Result:
- An allocation of a direct byte buffer and a copy of data is now not required for every SslHandler wrap operation.
Motivation:
The SslHandler wrap method requires that a direct buffer be passed to the SSLEngine.wrap() call. If the ByteBuf parameter does not have an underlying direct buffer then one is allocated in this method, but it is not released.
Modifications:
- Release the direct ByteBuffer only accessible in the scope of SslHandler.wrap
Result:
Memory leak in SslHandler.wrap is fixed.
Motivation:
As report in #2953 the websocket server example contained a bug and did therefore not work with chrome:
A websocket extension is added to the pipeline but extensions were disallowed in the handshaker and decoder,
which is leading the decoder to closing the connection after receiving an extension frame.
Modifications:
Allow websocket extensions in the handshaker to correctly enable the extension.
Result:
Working websocket server example
Fixes#2953
Motivation:
At the moment the whole HTTP header must be parsed at once which can lead to multiple parsing of the same bytes. We can do better here and allow to parse it in multiple steps.
Modifications:
- Not parse headers multiple times
- Simplify the code
- Eliminate uncessary String[] creations
- Use readSlice(...).retain() when possible.
Result:
Performance improvements as shown in the included benchmark below.
Before change:
[nmaurer@xxx]~% ./wrk-benchmark
Running 2m test @ http://xxx:8080/plaintext
16 threads and 256 connections
Thread Stats Avg Stdev Max +/- Stdev
Latency 21.55ms 15.10ms 245.02ms 90.26%
Req/Sec 196.33k 30.17k 297.29k 76.03%
373954750 requests in 2.00m, 50.15GB read
Requests/sec: 3116466.08
Transfer/sec: 427.98MB
After change:
[nmaurer@xxx]~% ./wrk-benchmark
Running 2m test @ http://xxx:8080/plaintext
16 threads and 256 connections
Thread Stats Avg Stdev Max +/- Stdev
Latency 20.91ms 36.79ms 1.26s 98.24%
Req/Sec 206.67k 21.69k 243.62k 94.96%
393071191 requests in 2.00m, 52.71GB read
Requests/sec: 3275971.50
Transfer/sec: 449.89MB
