Currently there is a clear mechanism to stub sending a request through
the transport. However, this is limited to testing exceptions on the
sender side. This commit reworks our transport related testing
infrastructure to allow stubbing request handling on the receiving side.
The use of available processors, the terminology, and the settings
around it have evolved over time. This commit cleans up some places in
the codes and in the docs to adjust to the current terminology.
This commit moves the action name validation and circuit breaking into
the InboundAggregator. This work is valuable because it lays the
groundwork for incrementally circuit breaking as data is received.
This PR includes the follow behavioral change:
Handshakes contribute to circuit breaking, but cannot be broken. They
currently do not contribute nor are they broken.
Currently all of our transport protocol decoding and aggregation occurs
in the individual transport modules. This means that each implementation
(test, netty, nio) must implement this logic. Additionally, it means
that the entire message has been read from the network before the server
package receives it.
This commit creates a pipeline in server which can be passed arbitrary
bytes to handle. Internally, the pipeline will decode, decompress, and
aggregate the messages. Additionally, this allows us to run many
megabytes of bytes through the pipeline in tests to ensure that the
logic works.
This work will enable future work:
Circuit breaking or backoff logic based on message type and byte
in the content aggregator.
Sharing bytes with the application layer using the ref counted
releasable network bytes.
Improved network monitoring based specifically on channels.
Finally, this fixes the bug where we do not circuit break on the correct
message size when compression is enabled.
Elasticsearch has a number of different BytesReference implementations.
These implementations can all implement the interface in different ways
with subtly different behavior and performance characteristics. On the
other-hand, the JVM only represents bytes as an array or a direct byte
buffer. This commit deletes the specialized Netty implementations and
moves to using a generic ByteBuffer reference type. This will allow us
to focus on standardizing performance and behave around a smaller number
of implementations that can be used by all components in Elasticsearch.
It is the job of the http server transport to release the request in the handler
but the mock fails to do so since we never override `incomingRequest`.
* Copying the request is not necessary here. We can simply release it once the response has been generated and a lot of `Unpooled` allocations that way
* Relates #32228
* I think the issue that preventet that PR that PR from being merged was solved by #39634 that moved the bulk index marker search to ByteBuf bulk access so the composite buffer shouldn't require many additional bounds checks (I'd argue the bounds checks we add, we save when copying the composite buffer)
* I couldn't neccessarily reproduce much of a speedup from this change, but I could reproduce a very measureable reduction in GC time with e.g. Rally's PMC (4g heap node and bulk requests of size 5k saw a reduction in young GC time by ~10% for me)
BytesReference is currently an abstract class which is extended by
various implementations. This makes it very difficult to use the
delegation pattern. The implication of this is that our releasable
BytesReference is a PagedBytesReference type and cannot be used as a
generic releasable bytes reference that delegates to any reference type.
This commit makes BytesReference an interface and introduces an
AbstractBytesReference for common functionality.
Elasticsearch does not grant Netty reflection access to get Unsafe. The
only mechanism that currently exists to free direct buffers in a timely
manner is to use Unsafe. This leads to the occasional scenario, under
heavy network load, that direct byte buffers can slowly build up without
being freed.
This commit disables Netty direct buffer pooling and moves to a strategy
of using a single thread-local direct buffer for interfacing with sockets.
This will reduce the memory usage from networking. Elasticsearch
currently derives very little value from direct buffer usage (TLS,
compression, Lucene, Elasticsearch handling, etc all use heap bytes). So
this seems like the correct trade-off until that changes.
Uses JDK 11's per-socket configuration of TCP keepalive (supported on Linux and Mac), see
https://bugs.openjdk.java.net/browse/JDK-8194298, and exposes these as transport settings.
By default, these options are disabled for now (i.e. fall-back to OS behavior), but we would like
to explore whether we can enable them by default, in particular to force keepalive configurations
that are better tuned for running ES.
Currently in the transport-nio work we connect and bind channels on the
a thread before the channel is registered with a selector. Additionally,
it is at this point that we set all the socket options. This commit
moves these operations onto the event-loop after the channel has been
registered with a selector. It attempts to set the socket options for a
non-server channel at registration time. If that fails, it will attempt
to set the options after the channel is connected. This should fix
#41071.
* Stop Passing Around REST Request in Multiple Spots
* Motivated by #44564
* We are currently passing the REST request object around to a large number of places. This works fine since we simply copy the full request content before we handle the rest itself which is needlessly hard on GC and heap.
* This PR removes a number of spots where the request is passed around needlessly. There are many more spots to optimize in follow-ups to this, but this one would already enable bypassing the request copying for some error paths in a follow up.
Today we have an annotation for controlling logging levels in
tests. This annotation serves two purposes, one is to control the
logging level used in tests, when such control is needed to impact and
assert the behavior of loggers in tests. The other use is when a test is
failing and additional logging is needed. This commit separates these
two concerns into separate annotations.
The primary motivation for this is that we have a history of leaving
behind the annotation for the purpose of investigating test failures
long after the test failure is resolved. The accumulation of these stale
logging annotations has led to excessive disk consumption. Having
recently cleaned this up, we would like to avoid falling into this state
again. To do this, we are adding a link to the test failure under
investigation to the annotation when used for the purpose of
investigating test failures. We will add tooling to inspect these
annotations, in the same way that we have tooling on awaits fix
annotations. This will enable us to report on the use of these
annotations, and report when stale uses of the annotation exist.
This commit moves the config that stores Cors options into the server
package. Currently both nio and netty modules must have a copy of this
config. Moving it into server allows one copy and the tests to be in a
common location.
Registering a channel with a selector is a required operation for the
channel to be handled properly. Currently, we mix the registeration with
other setup operations (ip filtering, SSL initiation, etc). However, a
fail to register is fatal. This PR modifies how registeration occurs to
immediately close the channel if it fails.
There are still two clear loopholes for how a user can interact with a
channel even if registration fails. 1. through the exception handler.
2. through the channel accepted callback. These can perhaps be improved
in the future. For now, this PR prevents writes from proceeding if the
channel is not registered.
Simplifies AbstractSimpleTransportTestCase to use JVM-local ports and also adds an assertion so
that cases like #44134 can be more easily debugged. The likely reason for that one is that a test,
which was repeated again and again while always spawning a fresh Gradle worker (due to Gradle
daemon) kept increasing Gradle worker IDs, causing an overflow at some point.
Currently nio implements ip filtering at the channel context level. This
is kind of a hack as the application logic should be implemented at the
handler level. This commit moves the ip filtering into a channel
handler. This requires adding an indicator to the channel handler to
show when a channel should be closed.
This is related to #27260. Currently we have a single read buffer that
is no larger than a single TLS packet. This prevents us from reading
multiple TLS packets in a single socket read call. This commit modifies
our TLS work to support reading similar to the plaintext case. The data
will be copied to a (potentially) recycled TLS packet-sized buffer for
interaction with the SSLEngine.
This fixes#41794. Currently the read timeout test queues up responses
in the netty pipeline. These responses are immediately returned in the
write call, but they are not released. This commit releases the
responses. This will cause the leak detector to quit throwing
exceptions.
This is related to #27260. Currently there is a setting
http.read_timeout that allows users to define a read timeout for the
http transport. This commit implements support for this functionality
with the transport-nio plugin. The behavior here is that a repeating
task will be scheduled for the interval defined. If there have been
no requests received since the last run and there are no inflight
requests, the channel will be closed.
This is related to #27260. Currently for the SSLDriver we allocate a
dedicated network write buffer and encrypt the data into that buffer one
buffer at a time. This requires constantly switching between encrypting
and flushing. This commit adds a dedicated outbound buffer for SSL
operations that will internally allocate new packet sized buffers as
they are need (for writing encrypted data). This allows us to totally
encrypt an operation before writing it to the network. Eventually it can
be hooked up to buffer recycling.
This commit also backports the following commit:
Handle WRAP ops during SSL read
It is possible that a WRAP operation can occur while decrypting
handshake data in TLS 1.3. The SSLDriver does not currently handle this
well as it does not have access to the outbound buffer during read call.
This commit moves the buffer into the Driver to fix this issue. Data
wrapped during a read call will be queued for writing after the read
call is complete.
This is related to #27260. Currently for the SSLDriver we allocate a
dedicated network write buffer and encrypt the data into that buffer one
buffer at a time. This requires constantly switching between encrypting
and flushing. This commit adds a dedicated outbound buffer for SSL
operations that will internally allocate new packet sized buffers as
they are need (for writing encrypted data). This allows us to totally
encrypt an operation before writing it to the network. Eventually it can
be hooked up to buffer recycling.
The xlint exclusions of the following plugins were removed:
* ingest-attachment.
* mapper-size.
* transport-nio. Removing the -try exclusion required some work, because
the NettyAdaptor implements AutoCloseable and NettyAdaptor#close() method
could throw an InterruptedException (ChannelFuture#await() and a generic
Exception is re-thrown, which maybe an ChannelFuture). The easiest way
around this to me seemed that NettyAdaptor should not implement AutoCloseable,
because it is not directly used in a try-with-resources statement.
Relates to #40366
This commit adds an InboundHandler to handle inbound message processing.
With this commit, this code is moved out of the TcpTransport.
Additionally, finer grained unit tests are added to ensure that the
inbound processing works as expected
Currently there are some components of message serializer and sending
that still occur in TcpTransport. This commit makes it possible to
send a message without the TcpTransport by moving all of the remaining
application logic to the OutboundHandler. Additionally, it adds unit
tests to ensure that this logic works as expected.
Currently, we maintain a transport name ("mock-nio", "nio", "netty")
that is passed to a `TcpTransportChannel` when a request is received.
The value of this name is to associate with the task when we register a
task with the task manager. However, it is only possible to run ES with
one transport, so having an implementation specific name is unnecessary.
This commit removes the name and replaces it with the generic
"transport".
* Optimize Bulk Message Parsing and Message Length Parsing
* findNextMarker took almost 1ms per invocation during the PMC rally track
* Fixed to be about an order of magnitude faster by using Netty's bulk `ByteBuf` search
* It is unnecessary to instantiate an object (the input stream wrapper) and throw it away, just to read the `int` length from the message bytes
* Fixed by adding bulk `int` read to BytesReference
This commit introduces a NetworkMessage class. This class has two
subclasses - InboundMessage and OutboundMessage. These messages can
be serialized and deserialized independent of the transport. This allows
more granular testing. Additionally, the serialization mechanism is now
a simple Supplier. This builds the framework to eventually move the
serialization of transport messages to the network thread. This is the
one serialization component that is not currently performed on the
network thread (transport deserialization and http serialization and
deserialization are all on the network thread).
Currently we create dedicated network threads for both the http and
transport implementations. Since these these threads should never
perform blocking operations, these threads could be shared. This commit
modifies the nio-transport to have 0 http workers be default. If the
default configs are used, this will cause the http transport to be run
on the transport worker threads. The http worker setting will still exist
in case the user would like to configure dedicated workers. Additionally,
this commmit deletes dedicated acceptor threads. We have never had these
for the netty transport and they can be added back if a need is
determined in the future.
This commit updates our transport settings for 7.0. It generally takes a
few approaches. First, for normal transport settings, it usestransport.
instead of transport.tcp. Second, it uses transport.tcp, http.tcp,
or network.tcp for all settings that are proxies for OS level socket
settings. Third, it marks the network.tcp.connect_timeout setting for
removal. Network service level settings are only settings that apply to
both the http and transport modules. There is no connect timeout in
http. Fourth, it moves all the transport settings to a single class
TransportSettings similar to the HttpTransportSettings class.
This commit does not actually remove any settings. It just adds the new
renamed settings and adds todos for settings that will be deprecated.
Currently our handshake requests do not include a version. This is
unfortunate as we cannot rely on the stream version since it is not the
sending node's version. Instead it is the minimum compatibility version.
The handshake request is currently empty and we do nothing with it. This
should allow us to add data to the request without breaking backwards
compatibility.
This commit adds the version to the handshake request. Additionally, it
allows "future data" to be added to the request. This allows nodes to craft
a version compatible response. And will properly handle additional data in
future handshake requests. The proper handling of "future data" is useful
as this is the only request where we do not know the other node's version.
Finally, it renames the TcpTransportHandshaker to
TransportHandshaker.
This commit modifies BigArrays to take a circuit breaker name and
the circuit breaking service. The default instance of BigArrays that
is passed around everywhere always uses the request breaker. At the
network level, we want to be using the inflight request breaker. So this
change will allow that.
Additionally, as this change moves away from a single instance of
BigArrays, the class is modified to not be a Releasable anymore.
Releasing big arrays was always dispatching to the PageCacheRecycler,
so this change makes the PageCacheRecycler the class that needs to be
managed and torn-down.
Finally, this commit closes#31435 be making the serialization of
transport messages use the inflight request breaker. With this change,
we no longer push the global BigArrays instnace to the network level.
This commit upgrades netty. This will close#35360. Netty started
throwing an IllegalArgumentException if a CompositeByteBuf is
created with < 2 components. Netty4Utils was updated to reflect this
change.
This is related to #34405 and a follow-up to #34753. It makes a number
of changes to our current keepalive pings.
The ping interval configuration is moved to the ConnectionProfile.
The server channel now responds to pings. This makes the keepalive
pings bidirectional.
On the client-side, the pings can now be optimized away. What this
means is that if the channel has received a message or sent a message
since the last pinging round, the ping is not sent for this round.
This commit removes the dedicated `setSoLinger` method. This simplifies
the `TcpChannel` interface. This method has very little effect as the
SO_LINGER is not set prior to the channels being closed in the abstract
transport test case. We still will set SO_LINGER on the
`MockNioTransport`. However we can do this manually.
This commit is related to #32517. It allows an "sni_server_name"
attribute on a DiscoveryNode to be propagated to the server using
the TLS SNI extentsion. Prior to this commit, this functionality
was only support for the netty transport. This commit adds this
functionality to the security nio transport.
This is related to #34483. It introduces a namespaced setting for
compression that allows users to configure compression on a per remote
cluster basis. The transport.tcp.compress remains as a fallback
setting. If transport.tcp.compress is set to true, then all requests
and responses are compressed. If it is set to false, only requests to
clusters based on the cluster.remote.cluster_name.transport.compress
setting are compressed. However, after this change regardless of any
local settings, responses will be compressed if the request that is
received was compressed.
This is related to #29023. Additionally at other points we have
discussed a preference for removing the need to unnecessarily block
threads for opening new node connections. This commit lays the groudwork
for this by opening connections asynchronously at the transport level.
We still block, however, this work will make it possible to eventually
remove all blocking on new connections out of the TransportService
and Transport.
Currently we create a new netty event loop group for client connections
and all server profiles. Each new group creates new threads for io
processing. This means 2 * num of processors new threads for each group.
A single group should be able to handle all io processing (for the
transports). This also brings the netty module inline with what we do
for nio.
Additionally, this PR renames the worker threads to be the same for
netty and nio.