Motivation
Currently every call to get() on a promise results in two reads of the
volatile result field when one would suffice. Maybe this is optimized
away but it seems sensible not to rely on that.
Modification
Reimplement get() and get(...) in DefaultPromise to reduce volatile access.
Result
Fewer volatile reads.
Motivation:
394a1b3485 added support for recvmmsg(...) for unconnected datagram channels, this change also allows to use recvmmsg(...) with connected datagram channels.
Modifications:
- Always try to use recvmmsg(...) if configured to do so
- Adjust unit test to cover it
Result:
Less syscalls when reading datagram packets
Motivation:
We should also use sendmmsg on connected channels whenever possible to reduce the overhead of syscalls.
Modifications:
No matter if the channel is connected or not try to use sendmmsg when supported to reduce the overhead of syscalls
Result:
Better performance on connected UDP channels due less syscalls
Motivation:
394a1b3485 introduced the possibility to use recvmmsg(...) but did not correctly handle ipv6 mapped ip4 addresses to make it consistent with other transports.
Modifications:
- Correctly handle ipv6 mapped ipv4 addresses by only copy over the relevant bytes
- Small improvement on how to detect ipv6 mapped ipv4 addresses by using memcmp and not byte by byte compare
- Adjust test to cover this bug
Result:
Correctly handle ipv6 mapped ipv4 addresses
Motivation
problem with Throwable#addSuppressed() raised in #9151. This introduced
a performance issue when promises are cancelled at a high frequency due
to the construction cost of CancellationException at the time that
DefaultPromise#cancel() is called.
Modifications
- Reinstate the prior static CANCELLATION_CAUSE_HOLDER but use it just
as a sentinel to indicate cancellation, constructing a new
CancellationException only if/when one needs to be explicitly
returned/thrown
- Subclass CancellationException, overriding fillInStackTrace() to
minimize the construction cost in these cases
Result
Promises are much cheaper to cancel. Fixes#9522.
Motiviation:
EmbeddedChannel currently is quite differently in terms of semantics to other Channel implementations. We should better change it to be more closely aligned and so have the testing code be more robust.
Modifications:
- Change EmbeddedEventLoop.inEventLoop() to only return true if we currenlty run pending / scheduled tasks
- Change EmbeddedEventLoop.execute(...) to automatically process pending tasks if not already doing so
- Adjust a few tests for the new semantics (which is closer to other Channel implementations)
Result:
EmbeddedChannel works more like other Channel implementations
Motivation:
At the moment it is quite easy to hit reentrance issues when you have multiple handlers in the pipeline and each of the handlers does not correctly protect against these. To make it easier for the user we should try to protect from these. The issue is usually if and inbound event will trigger and outbound event and this outbound event then against triggeres an inbound event. This may result in having methods in a ChannelHandler re-enter some method and so state can be corrupted or messages be re-ordered.
Modifications:
- Keep track of inbound / outbound operations in DefaultChannelHandlerContext and if reentrancy is detected break it by scheduling the action on the EventLoop. This will then be picked up once the method returns and so the reentrancy is broken up.
- Adjust tests which made strange assumptions about execution order
Result:
No more reentrancy of handlers possible.
Motivation:
When using datagram sockets which need to handle a lot of packets it makes sense to use recvmmsg to be able to read multiple datagram packets with one syscall.
Modifications:
- Add support for recvmmsg on linux
- Add new EpollChannelOption.MAX_DATAGRAM_PACKET_SIZE
- Add tests
Result:
Fixes https://github.com/netty/netty/issues/8446.
Motivation
This is a "simpler" alternative to #9416 which fixes the same
CompositeByteBuf bugs described there, originally reported by @jingene
in #9398.
Modifications
- Add fields to Component class for the original buffer along with its
adjustment, which may be different to the already-stored unwrapped
buffer. Use it in appropriate places to ensure correctness and
equivalent behaviour to that prior to the earlier optimizations
- Add comments explaining purpose of each of the Component fields
- Unwrap more kinds of buffers in newComponent method to extend scope of
the existing indirection-reduction optimization
- De-duplicate common buffer consolidation logic
- Unit test for the original bug provided by @jingene
Result
- Correct behaviour / fixed bugs
- Some code deduplication / simplification
- Unwrapping optimization applied to more types of buffers
The downside is increased mem footprint from the two new fields, and
additional allocations in some specific cases, though those should be
rare.
Co-authored-by: jingene <jingene0206@gmail.com>
Motivation:
There are some extra log level checks (logger.isWarnEnabled()).
Modification:
Remove log level checks (logger.isWarnEnabled()) from io.netty.channel.epoll.AbstractEpollStreamChannel, io.netty.channel.DefaultFileRegion, io.netty.channel.nio.AbstractNioChannel, io.netty.util.HashedWheelTimer, io.netty.handler.stream.ChunkedWriteHandler and io.netty.channel.udt.nio.NioUdtMessageConnectorChannel
Result:
Fixes#9456
Motivation:
At the moment we use the String representation of the IP to create the DatagramSocketAddress. This is not for free and we should better use the byte[] directly to reduce the overhead of parsing the String (and creating it in the first place)
Modifications:
Directly use byte[] as input for the DatagramSocketAddress
Result:
Less overhead when using Datagrams with native transports
Motivation:
The Netty classes are initialized at build time by default for GraalVM Native Image compilation. This is configured via the `--initialize-at-build-time=io.netty` option. While this reduces start-up time it can lead to some problems:
- The class initializer of `io.netty.buffer.PooledByteBufAllocator` looks at the maximum memory size to compute the size of internal buffers. If the class initializer runs during image generation, then the buffers are sized according to the very large heap size that the image generator uses, and Netty allocates several arrays that are 16 MByte. The fix is to initialize the following 3 classes at run time: `io.netty.buffer.PooledByteBufAllocator,io.netty.buffer.ByteBufAllocator,io.netty.buffer.ByteBufUtil`. This fix was dependent on a GraalVM Native Image fix that was included in 19.2.0.
- The class initializer of `io.netty.handler.ssl.util.ThreadLocalInsecureRandom` needs to be initialized at runtime to ensure that the generated values are trully random and not fixed for each generated image.
- The class initializers of `io.netty.buffer.AbstractReferenceCountedByteBuf` and `io.netty.util.AbstractReferenceCounted` compute field offsets. While the field offset recomputation is necessary for correct execution as a native image these initializers also have logic that depends on the presence/absence of `sun.misc.Unsafe`, e.g., via the `-Dio.netty.noUnsafe=true` flag. The fix is to push these initializers to runtime so that the field offset lookups (and the logic depending on them) run at run time. This way no manual substitutions are necessary either.
Modifications:
Add `META-INF/native-image` configuration files that correctly trigger the inialization of the above classes at run time via `--initialize-at-run-time=...` flags.
Result:
Fixes the initialisation issues described above for Netty executables built with GraalVM.
Motivation:
Currently when HttpPostStandardRequestDecoder throws a ErrorDataDecoderException during construction we leak memory. We need to ensure all is released correctly.
Modifications:
- Call destroy() if parseBody() throws and rethrow the ErrorDataDecoderException
- Add unit test
Result:
Fixes https://github.com/netty/netty/issues/9513.
Motivation:
We need to also include the native-image configuration files in the netty all jar to be able to use it with GraalVM native.
Modifications:
Add files in META-INF/native-image as well
Result:
Fixes https://github.com/netty/netty/issues/9514
Motivation:
We currently try to access the the domain search list via reflection on windows which will print a illegal access warning when using Java9 and later.
Modifications:
Add a guard against the used java version.
Result:
Fixes https://github.com/netty/netty/issues/9500.
Motivation:
Right now you can cancel the Future returned by
`Http2StreamChannelBootstrap.open()` and that will race with the
registration of the stream channel with the event loop, potentially
culminating in an `IllegalStateException` and potential resource leak.
Modification:
Ensure that the returned promise is uncancellable.
Result:
Should no longer see `IllegalStateException`s.
Motivation:
We did not correctly pass all supplied parameters to the called constructor and so did not apply the timeout.
Modification:
Correctly pass on the parameters.
Result:
Use timeout
Motivation:
AbstractByteBuf.indexOf(...) currently delegates to ByteBufUtils.indexOf(...) which will create a new ByteBufProcessor on each call. This is done to reduce overhead of bounds-checks. Unfortunally while this reduces bounds checks it produces a lot of GC. We can just implement our own version in AbstractByteBuf which makes use of _getByte(...) and so does no bound checks as well but also not need to create any garbage.
Modifications:
Write optimized implementation of indexOf(...) for AbstractByteBuf
Result:
Fixes https://github.com/netty/netty/issues/9499.
Motivation:
In the release (4.1.37) we introduced Http2MultiplexHandler as a
replacement of Http2MultiplexCodec. This did split the frame parsing from
the multiplexing to allow a more flexible way to handle frames and to make
the code cleaner. Unfortunally we did miss to special handle this in
Http2ClientUpgradeCodec and so did not correctly add Http2MultiplexHandler
to the pipeline before calling Http2FrameCodec.onHttpClientUpgrade(...).
This did lead to the situation that we did not correctly receive the event
on the Http2MultiplexHandler and so did not correctly created the
Http2StreamChannel for the upgrade stream. Because of this we ended up
with an NPE if a frame was dispatched to the upgrade stream later on.
Modifications:
- Correctly add Http2MultiplexHandler to the pipeline before calling Http2FrameCodec.onHttpClientUpgrade(...)
Result:
Fixes#9495.
Motivation:
We should not only include the java source files but also the c source file in our source jars.
Modifications:
Add files from src/main/c as well
Result:
Fixes https://github.com/netty/netty/issues/9494
Motivation:
Some of the links in javadoc point to the obsolete drafts of HTTP/2
specifications. We should point them to the latest RFC 7540 or 7541.
Modifications:
Update links from `draft-ietf-httpbis-*` to the `rfc7540` and `rfc7541`.
Result:
Correct links in javadoc.
Motivation:
`HttpObjectDecoder` pre-checks that it doesn't request characters
outside of the `AppendableCharSequence`'s length. `0` is always allowed
because the minimal length of `AppendableCharSequence` is `1`. We can
legally skip index check by using
`AppendableCharSequence.charAtUnsafe(int)` in all existing cases in
`HttpObjectDecoder`.
Modifications:
- Use `AppendableCharSequence.charAtUnsafe(int)` instead of
`AppendableCharSequence.charAt(int)` in `HttpObjectDecoder`.
Result:
No unnecessary index checks in `HttpObjectDecoder`.
Motivation:
14607979f6 added tests for using ACCP but did miss to use the same unwrapping technique of exceptions as JdkSslEngineTest. This can lead to test-failures on specific JDK versions
Modifications:
Add the same unwrapping code
Result:
No more test failures
Motivation:
Amazon lately released Amazon Corretto Crypto Provider, so we should include it in our testsuite
Modifications:
Add tests related to Amazon Corretto Crypto Provider
Result:
Test netty with Amazon Corretto Crypto Provider
Motivation:
Http post request may be encoded as 'multipart/form-data' without any files and consist mixed attributes only.
Modifications:
- Do not double release attributes
- Add unit test
Result:
Code does not throw an IllegalReferenceCountException.
Motivation
Currently an epoll_ctl syscall is made every time there is a change to
the event interest flags (EPOLLIN, EPOLLOUT, etc) of a channel. These
are only done in the event loop so can be aggregated into 0 or 1 such
calls per channel prior to the next call to epoll_wait.
Modifications
I think further streamlining/simplification is possible but for now I've
tried to minimize structural changes and added the aggregation beneath
the existing flag manipulation logic.
A new AbstractChannel#activeFlags field records the flags last set on
the epoll fd for that channel. Calls to setFlag/clearFlag update the
flags field as before but instead of calling epoll_ctl immediately, just
set or clear a bit for the channel in a new bitset in the associated
EpollEventLoop to reflect whether there's any change to the last set
value.
Prior to calling epoll_wait the event loop makes the appropriate
epoll_ctl(EPOLL_CTL_MOD) call once for each channel who's bit is set.
Result
Fewer syscalls, particularly in some auto-read=false cases. Simplified
error handling from centralization of these calls.
Motivation:
We need to ensure we replace WebSocketServerProtocolHandshakeHandler before doing the actual handshake as the handshake itself may complete directly and so forward pending bytes through the pipeline.
Modifications:
Replace the handler before doing the actual handshake.
Result:
Fixes https://github.com/netty/netty/issues/9471.
Motivation:
It is possible that the user uses a too big EDNS0 setting for the MTU and so we may receive a truncated datagram packet. In this case we should try to detect this and retry via TCP if possible
Modifications:
- Fix detecting of incomplete records
- Mark response as truncated if we did not consume the whole packet
- Add unit test
Result:
Fixes https://github.com/netty/netty/issues/9365
Motivation:
AsciiString.contentEqualsIgnoreCase may return true for non-matching strings of equal length when offset is non zero.
Modifications:
- Correctly take offset into account
- Add unit test
Result:
Fixes#9475
Motivation:
If all we need is the FileChannel we should better use RandomAccessFile as FileInputStream and FileOutputStream use a finalizer.
Modifications:
Replace FileInputStream and FileOutputStream with RandomAccessFile when possible.
Result:
Fixes https://github.com/netty/netty/issues/8078.
Motivation:
In AbstractBoostrap, options and attrs are LinkedHashMap that are synchronized on for every read, copy/clone, write operation.
When a lot of connections are triggered concurrently on the same bootstrap instance, the synchronized blocks lead to contention, Netty IO threads get blocked, and performance may be severely degraded.
Modifications:
Use ConcurrentHashMap
Result:
Less contention. Fixes https://github.com/netty/netty/issues/9426
Motivation:
We should use the same java versions whenever we use CentOS 6 or 7 and also use the latest Java12 version
Modifications:
- Use same Java versions
- Use latest Java 12 version
- Remove old configs which are not used anymore
Result:
Docker cleanup
Motivation:
We should better update the flow-controller on Channel.read() to reduce overhead and memory overhead.
See https://github.com/netty/netty/pull/9390#issuecomment-513008269
Modifications:
Move updateLocalWindowIfNeeded() to doBeginRead()
Result:
Reduce memory overhead
Motivation
region is preserved when capacity is increased, not just the readable
part. The behaviour is still different however when the capacity is
_decreased_ - data outside the currently-readable region is zeroed.
Modifications
Update ByteBuf capacity(int) implementations to also copy the whole
buffer region when the new capacity is less than the current capacity.
Result
Consistent behaviour of ByteBuf#capacity(int) regardless of whether the
new capacity is greater than or less than the current capacity.
Motivation:
It was possible to produce a NPE when we for examples received more responses as requests as we did not check if the queue did not contain a method before trying to compare method names.
Modifications:
- Add extra null check
- Add unit tet
Result:
Fixes https://github.com/netty/netty/issues/9459
Motivation:
As we decorate the Http2FrameListener under the covers we should ensure the user can still access the original Http2FrameListener.
Modifications:
- Unwrap the Http2FrameListener in frameListener()
- Add unit test
Result:
Less suprises for users.
Motivation:
We should only ever close the underlying tcp socket once we received the envelope to ensure we never race in the test.
Modifications:
- Only close socket once we received the envelope
- Set REUSE_ADDR
Result:
More robust test
Motivation:
We did not correctly pass the mask parameters in all cases.
Modifications:
Correctly pass on parameters
Result:
Fixes https://github.com/netty/netty/issues/9463.
Motivation:
We recently introduced Http2ControlFrameLimitEncoderTest which did not correctly notify the goAway promises and so leaked buffers.
Modifications:
Correctly notify all promises and so release the debug data.
Result:
Fixes leak in HTTP2 test
Motivation:
It is possible for a remote peer to flood the server / client with empty DATA frames (without end_of_stream flag) set and so cause high CPU usage without the possibility to ever hit a limit. We need to guard against this.
See CVE-2019-9518
Modifications:
- Add a new config option to AbstractHttp2ConnectionBuilder and sub-classes which allows to set the max number of consecutive empty DATA frames (without end_of_stream flag). After this limit is hit we will close the connection. A limit of 10 is used by default.
- Add unit tests
Result:
Guards against CVE-2019-9518
Motivation:
Due how http2 spec is defined it is possible by a remote peer to flood us with frames that will trigger control frames as response, the problem here is that the remote peer can also just stop reading these (while still produce more of these) and so may drive us to the pointer where we either run out of memory or burn all CPU. To protect against this we need to implement some kind of limit that will tear down connections that cause the above mentioned situation.
See CVE-2019-9512 / CVE-2019-9514 / CVE-2019-9515
Modifications:
- Add Http2ControlFrameLimitEncoder which limits the number of queued control frames that were caused because of the remote peer.
- Allow to insert ths Http2ControlFrameLimitEncoder by setting AbstractHttp2ConnectionBuilder.encoderEnforceMaxQueuedControlFrames(...) to a number higher then 0. The default is 10000 which provides some protection by default but will hopefully not cause too many false-positives.
- Add unit tests
Result:
Protect against DDOS due control frames. Fixes CVE-2019-9512 / CVE-2019-9514 / CVE-2019-9515 .
Motivation
Underlying array allocations in UnpooledHeapByteBuf are intended be done
via the protected allocateArray(int) method, so that they can be tracked
and/or overridden by subclasses, for example
UnpooledByteBufAllocator$InstrumentedUnpooledHeapByteBuf or #8015. But
it looks like an explicit allocation was missed in the copy(int,int)
method.
Modification
Just use alloc().heapBuffer(...) for the allocation
Result
No possibility of "missing" array allocations when ByteBuf#copy is used.
Motivation:
We should delay the firing of the Http2ConnectionPrefaceAndSettingsFrameWrittenEvent by one EventLoop tick when using the Http2FrameCodec to ensure all handlers are added to the pipeline before the event is passed through it.
This is needed to workaround a race that could happen when the preface is send in handlerAdded(...) but a later handler wants to act on the event.
Modifications:
Offload firing of the event to the EventExecutor.
Result:
Fixes https://github.com/netty/netty/issues/9432.
Motivation:
As we use the docker files for the CI we should use the delegated mount option to speed up builds.
See https://docs.docker.com/docker-for-mac/osxfs-caching/#delegated
Modifications:
Use delegated mount option
Result:
Faster builds when using docker
Motivation:
When using OpenSSL and JDK < 11 is used we need to wrap the user provided X509ExtendedTrustManager to be able to support TLS1.3. We had a check in place that first tried to see if wrapping is needed at all which could lead to missleading calls of the user provided trustmanager. We should remove these calls and just always wrap if needed.
Modifications:
Always wrap if OpenSSL + JDK < 11 and TLS1.3 is supported
Result:
Less missleading calls to user provided trustmanager
