Motivation:
At the moment we only forward decoded messages that were added the out List once the full decode loop was completed. This has the affect that resources may not be released as fast as possible and as an application may incounter higher latency if the user triggeres a writeAndFlush(...) as a result of the decoded messages.
Modifications:
- forward decoded messages after each decode call
Result:
Forwarding decoded messages through the pipeline in a more eager fashion.
Motivation:
If a remote peer writes fast enough it may take a long time to have fireChannelReadComplete(...) triggered. Because of this we need to take special care and ensure we try to discard some bytes if channelRead(...) is called to often in ByteToMessageDecoder.
Modifications:
- Add ByteToMessageDecoder.setDiscardAfterReads(...) which allows to set the number of reads after which we try to discard the read bytes
- Use default value of 16 for max reads.
Result:
No risk of OOME.
Motivation:
We missed to correctly implement the handlerRemoved(...) / channelInactive(...) and channelReadComplete(...) method, this leaded to multiple problems:
- Missed to forward bytes when the codec is removed from the pipeline
- Missed to call decodeLast(...) once the Channel goes in active
- No correct handling of channelReadComplete that could lead to grow of cumulation buffer.
Modifications:
- Correctly implement methods and forward to the internal ByteToMessageDecoder
- Add unit test.
Result:
Correct behaviour
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 are currently doing a memory cop to extract the frame in LengthFieldBasedFrameDecoder which can be eliminated.
Modifications:
Use buffer.slice(...).retain() to eliminate the memory copy.
Result:
Better performance.
Motivation:
The LineBasedFrameDecoder discardedBytes counting different compare to
DelimiterBasedFrameDecoder.
Modifications:
Add plus sign
Result:
DiscardedBytes counting correctly
Motivation:
Our automatically handling of non-auto-read failed because it not detected the need of calling read again by itself if nothing was decoded. Beside this handling of non-auto-read never worked for SslHandler as it always triggered a read even if it decoded a message and auto-read was false.
This fixes [#3529] and [#3587].
Modifications:
- Implement handling of calling read when nothing was decoded (with non-auto-read) to ByteToMessageDecoder again
- Correctly respect non-auto-read by SslHandler
Result:
No more stales and correctly respecting of non-auto-read by SslHandler.
Motivation:
The ReplayingDecoderBuffer does not match the naming scheme we use for ByteBuf types.
Modifications:
Rename to ReplayingDecoderByteBuf to match naming scheme
Result:
Consistent naming
Motivation:
While the LengthFieldBasedFrameDecoder supports a byte order the LengthFieldPrepender does not.
That means that I can simply add a LengthFieldBasedFrameDecoder with ByteOrder.LITTLE_ENDIAN to my pipeline
but have to write my own Encoder to write length fields in little endian byte order.
Modifications:
Added a constructor that takes a byte order and all other parameters.
All other constructors delegate to this one with ByteOrder.BIG_ENDIAN.
LengthFieldPrepender.encode() uses this byte order to write the length field.
Result:
LengthFieldPrepender will write the length field in the defined byte order.
Motivation:
This will avoid one unncessary method invokation which will slightly improve performance.
Modifications:
Instead of calling isReadable we just check for the value of readableBytes()
Result:
Nothing functionally speaking change.
Related:
- 8b2fb2b985
Motivation:
The commit mentioned above introduced a regression where
channelReadComplete() event is swallowed by a handler which was added
dynamically.
Modifications:
Do not suppress channelReadComplete() if the current handler's
channelRead() method was not invoked at all, so that a just-added
handler does not suppress channelReadComplete().
Result:
Regression is gone, and channelReadComplete() is invoked when necessary.
Motivation:
The JdkZlibDecoder and JZlibDecoder call isReadable and readableBytes in the same method. There is an opportunity to reduce the number of methods calls to just use readableBytes. JdkZlibDecoder reads from a ByteBuf with an absolute index instead of using readerIndex()
Modifications:
- Use readableBytes where isReadable was used
- Correct absolute ByteBuf index to be relative to readerIndex()
Result:
Less method calls duplicating work and preventing an index out of bounds exception.
Motivation:
ctx.fireChannelReadComplete() should only be called if something is produced during a channelRead(...) operation. Also we must ensure that it will be called
if channelRead(...) produced something at some point as channelRead(...) maybe called multiple times by the transport before channelReadComplete(...) is called.
Modifications:
- Ensure channelReadComplete(...) only triggers ctx.fireChannelReadComplete() when a previous channelRead(...) call produced a message
- Ensure read() is called of more data is needed
Result:
Correct semantic with channelReadComplete(...) events and also ensure no stales
Motivation:
Currently when there are bytes left in the cumulation buffer we do a byte copy to produce the input buffer for the decode method. This can put quite some overhead on the impl.
Modification:
- Use a CompositeByteBuf to eliminate the byte copy.
- Allow to specify if a CompositeBytebug should be used or not as some handlers can only act on one ByteBuffer in an efficient way (like SslHandler :( ).
Result:
Performance improvement as shown in the following benchmark.
Without this patch:
[xxx@xxx ~]$ ./wrk-benchmark
Running 5m test @ http://xxx:8080/plaintext
16 threads and 256 connections
Thread Stats Avg Stdev Max +/- Stdev
Latency 20.19ms 38.34ms 1.02s 98.70%
Req/Sec 241.10k 26.50k 303.45k 93.46%
1153994119 requests in 5.00m, 155.84GB read
Requests/sec: 3846702.44
Transfer/sec: 531.93MB
With the patch:
[xxx@xxx ~]$ ./wrk-benchmark
Running 5m test @ http://xxx:8080/plaintext
16 threads and 256 connections
Thread Stats Avg Stdev Max +/- Stdev
Latency 17.34ms 27.14ms 877.62ms 98.26%
Req/Sec 252.55k 23.77k 329.50k 87.71%
1209772221 requests in 5.00m, 163.37GB read
Requests/sec: 4032584.22
Transfer/sec: 557.64MB
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
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:
ExtensionRegistry is a subclass of ExtensionRegistryLite. The ProtobufDecoder
doesn't use the registry directly, it simply passes it through to the Protobuf
API. The Protobuf calls in question are themselves written in terms
ExtensionRegistryLite not ExtensionRegistry.
Modifications:
Require ExtensionRegistryLite instead of ExtensionRegistry in ProtobufDecoder.
Result:
Consumers can use ExtensionRegistryLite with ProtobufDecoder.
Related issue: #2821
Motivation:
There's no way for a user to change the default ZlibEncoder
implementation.
It is already possible to change the default ZlibDecoder implementation.
Modification:
Add a new system property 'io.netty.noJdkZlibEncoder'.
Result:
A user can disable JDK ZlibEncoder, just like he or she can disable JDK
ZlibDecoder.
Motivation:
We have some duplicated code that can be reused.
Modifications:
Create package private class called CodecUtil that now contains the shared code / helper method.
Result:
Less code-duplication
Motivation:
ByteToMessageCodec miss to check for @Sharable annotation in one of its constructors.
Modifications:
Ensure we call checkForSharableAnnotation in all constructors.
Result:
After your change, what will change.
