This commit attempts to continue unifying the logic between different
transport implementations. As transports call a `TcpTransport` callback
when a new channel is accepted, there is no need to internally track
channels accepted. Instead there is a set of accepted channels in
`TcpTransport`. This set is used for metrics and shutting down channels.
This is related to #27563. This commit modifies the
InboundChannelBuffer to support releasable byte pages. These byte
pages are provided by the PageCacheRecycler. The PageCacheRecycler
must be passed to the Transport with this change.
We currently do not have any server-side read timeouts implemented in
elasticsearch. This commit adds a read timeout setting that defaults to
30 seconds. If after 30 seconds a read has not occurred, the channel
will be closed. A timeout of value of 0 will disable the timeout.
This is related to #27422. Right now when we send a write to the netty
transport, we attach a listener to the future. When you submit a write
on the netty event loop and the event loop is shutdown, the onFailure
method is called. Unfortunately, netty then tries to notify the listener
which cannot be done without dispatching to the event loop. In this
case, the dispatch fails and netty logs and error and does not tell us.
This commit checks that netty is still not shutdown after sending a
message. If netty is shutdown, we complete the listener.
Currently we use ActionListener<TcpChannel> for connect, close, and send
message listeners in TcpTransport. However, all of the listeners have to
capture a reference to a channel in the case of the exception api being
called. This commit changes these listeners to be type <Void> as passing
the channel to onResponse is not necessary. Additionally, this change
makes it easier to integrate with low level transports (which use
different implementations of TcpChannel).
This commit is a follow up to the work completed in #27132. Essentially
it transitions two more methods (sendMessage and getLocalAddress) from
Transport to TcpChannel. With this change, there is no longer a need for
TcpTransport to be aware of the specific type of channel a transport
returns. So that class is no longer parameterized by channel type.
Right now our different transport implementations must duplicate
functionality in order to stay compliant with the requirements of
TcpTransport. They must all implement common logic to open channels,
close channels, keep track of channels for eventual shutdown, etc.
Additionally, there is a weird and complicated relationship between
Transport and TransportService. We eventually want to start merging
some of the functionality between these classes.
This commit starts moving towards a world where TransportService retains
all the application logic and channel state. Transport implementations
in this world will only be tasked with returning a channel when one is
requested, calling transport service when a channel is accepted from
a server, and starting / stopping itself.
Specifically this commit changes how channels are opened and closed. All
Transport implementations now return a channel type that must comply with
the new TcpChannel interface. This interface has the methods necessary
for TcpTransport to completely manage the lifecycle of a channel. This
includes setting the channel up, waiting for connection, adding close
listeners, and eventually closing.
This is a followup to #26521. This commit expands the alias added for
the elasticsearch client codebase to all codebases. The original full
jar name property is left intact. This only adds an alias without the
version, which should help ease the pain in updating any versions (ES
itself or dependencies).
If creating the REST request throws an exception (for example, because
of invalid headers), we leak the request due to failure to release the
buffer (which would otherwise happen after replying on the
channel). This commit addresses this leak by handling the failure case.
Relates #27222
This commit removes the `ByteBufStreamInput` `readBytesReference` and
`readBytesRef` methods. These methods are zero-copy which means that
they retain a reference to the underlying netty buffer. The problem is
that our `TcpTransport` is not designed to handle zero-copy. The netty
implementation sets the read index past the current message once it has
been deserialized, handled, and mostly likely dispatched to another
thread. This means that netty is free to release this buffer. So it is
unsafe to retain a reference to it without calling `retain`. And we
cannot call `retain` because we are not currently designed to handle
reference counting past the transport level.
This should not currently impact us as we wrap the `ByteBufStreamInput`
in `NamedWriteableAwareStreamInput` in the `TcpTransport`. This stream
essentially delegates to the underling stream. However, in the case of
`readBytesReference` and `readBytesRef` it leaves thw implementations
to the standard `StreamInput` methods. These methods call the read byte
array method which delegates to `ByteBufStreamInput`. The read byte
array method on `ByteBufStreamInput` copies so it is safe. The only
impact of this commit should be removing methods that could be dangerous
if they were eventually called due to some refactoring.
Right now we are attempting to set SO_LINGER to 0 on server channels
when we are stopping the tcp transport. This is not a supported socket
option and throws an exception. This also prevents the channels from
being closed.
This commit 1. doesn't set SO_LINGER for server channges, 2. checks
that it is a supported option in nio, and 3. changes the log message
to warn for server channel close exceptions.
While opening a connection to a node, a channel can subsequently
close. If this happens, a future callback whose purpose is to close all
other channels and disconnect from the node will fire. However, this
future will not be ready to close all the channels because the
connection will not be exposed to the future callback yet. Since this
callback is run once, we will never try to disconnect from this node
again and we will be left with a closed channel. This commit adds a
check that all channels are open before exposing the channel and throws
a general connection exception. In this case, the usual connection retry
logic will take over.
Relates #26932
With this commit we simplify our network layer by only allowing to define a
fixed receive predictor size instead of a minimum and maximum value. This also
means that the following (previously undocumented) settings are removed:
* http.netty.receive_predictor_min
* http.netty.receive_predictor_max
Using an adaptive sizing policy in the receive predictor is a very low-level
optimization. The implications on allocation behavior are extremely hard to grasp
(see our previous work in #23185) and adaptive sizing does not provide a lot of
benefits (see benchmarks in #26165 for more details).
* Add additional low-level logging handler
We have the trace handler which is useful for recording sent messages
but there are times where it would be useful to have more low-level
logging about the events occurring on a channel. This commit adds a
logging handler that can be enabled by setting a certain log level
(org.elasticsearch.transport.netty4.ESLoggingHandler) to trace that
provides trace logging on low-level channel events and includes some
information about the request/response read/write events on the channel
as well.
* Remove imports
* License header
* Remove redundant
* Add test
* More assertions
We should unwrap the cause looking for any suppressed errors or root
causes that are errors when checking if we should maybe die. This commit
causes that to be the case.
Relates #26884
This commit changes the log level on a write and flush failure to warn
as this is not necessarily an Elasticsearch problem but more likely
indicative of an infrastructure problem.
This commit fixes a #26855. Right now we set SO_LINGER to 0 if we are
stopping the transport. This can throw a ChannelClosedException if the
raw channel is already closed. We have a number of scenarios where it is
possible this could be called with a channel that is already closed.
This commit fixes the issue be checking that the channel is not closed
before attempting to set the socket option.
This commit reorders a maybe die check and a logging statement for the
following reasons:
- we should die as quickly as possible if the cause is fatal
- we do not want the JVM to be so broken that when we try to log
another exception is thrown (maybe another out of memory exception)
and then the maybe die is never invoked
- maybe die will log the cause anyway if the cause is fatal so we only
need to log if the cause is not fatal
At current, we do not feel there is enough of a reason to shade the low
level rest client. It caused problems with commons logging and IDE's
during the brief time it was used. We did not know exactly how many
users will need this, and decided that leaving shading out until we
gather more information is best. Users can still shade the jar
themselves. For information and feeback, see issue #26366.
Closes#26328
This reverts commit 3a20922046.
This reverts commit 2c271f0f22.
This reverts commit 9d10dbea39.
This reverts commit e816ef89a2.
There is a group of five settings relating to raw tcp configurations
(no_delay, buffer sizes, etc) that we have for the http transport. These
currently live in the netty module. As they are unrelated to netty
specifically, this commit moves these settings to the
`HttpTransportSettings` class in core.
Right now it is possible for the `HttpPipeliningHandler` to queue
pipelined responses. On channel close, we do not clear and release these
responses. This commit releases the responses and completes the promise.
With this commit we remove the following three previously unused
(and undocumented) Netty 4 related settings:
* transport.netty.max_cumulation_buffer_capacity,
* transport.netty.max_composite_buffer_components and
* http.netty.max_cumulation_buffer_capacity
from Elasticsearch.
This commit fixes an issue with the Netty 4 multi-port test that a
transport client can connect. The problem here is that in case the
bottom of the random port range was already bound to (for example, by
another JVM) then then transport client could not connect to the data
node. This is because the transport client was in fact using the bottom
of the port range only. Instead, we simply try all the ports that the
data node might be bound to.
Closes#24441
This commit removes all external dependencies from the rest client jar
and shades them in an 'org.elasticsearch.client' package within the jar
using shadowJar gradle plugin. All projects that depended on the
existing jar have been converted to using the 'org.elasticsearch.client'
package prefixes to interact with the rest client.
Closes#25208
There is a bug when a call to `BytesReferenceStreamInput` skip is made
on a `BytesReference` that has an initial offset. The offset for the
current slice is added to the current index and then subtracted from the
length. This introduces the possibility of a negative number of bytes to
skip. This happens inside a loop, which leads to an infinte loop.
This commit correctly subtracts the current slice index from the
slice.length. Additionally, the `BytesArrayTests` are modified to test
instances that include an offset.
Currently when we close a channel in Netty4Utils.closeChannels we
block until the closing is complete. This introduces the possibility
that a network selector thread will block while waiting until a
separate network selector thread closes a channel.
For instance: T1 closes channel 1 (which is assigned to a T1 selector).
Channel 1's close listener executes the closing of the node. That
means that T1 now tries to close channel 2. However, channel 2 is
assigned to a selector that is running on T2. T1 now must wait until T2
closes that channel at some point in the future.
This commit addresses this by adding a boolean to closeChannels
indicating if we should block on close. We only set this boolean to true
if we are closing down the server channels at shutdown. This call is
never made from a network thread. When we call the closeChannels method
with that boolean set to false, we do not block on close.
Transport profiles unfortunately have never been validated. Yet, it's very
easy to make a mistake when configuring profiles which will most likely stay
undetected since we don't validate the settings but allow almost everything
based on the wildcard in `transport.profiles.*`. This change removes the
settings subset based parsing of profiles but rather uses concrete affix settings
for the profiles which makes it easier to fall back to higher level settings since
the fallback settings are present when the profile setting is parsed. Previously, it was
unclear in the code which setting is used ie. if the profiles settings (with removed
prefixes) or the global node setting. There is no distinction anymore since we don't pull
prefix based settings.
This commit makes the use of the global network settings explicit instead
of implicit within NetworkService. It cleans up several places where we fall
back to the global settings while we should have used tcp or http ones.
In addition this change also removes unnecessary settings classes
These settings have not be working for a full major version since they
are not registered. Given that they are simply duplicates we can just remove
them.
Today TcpTransport is the de-facto base-class for transport implementations.
The need for all the callbacks we have in TransportServiceAdaptor are not necessary
anymore since we can simply have the logic inside the base class itself. This change
moves the stats metrics directly into TcpTransport removing the need for low level
bytes send / received callbacks.
We use assertBusy in many places where the underlying code throw exceptions. Currently we need to wrap those exceptions in a RuntimeException which is ugly.
Today if a channel gets closed due to a disconnect we notify the response
handler that the connection is closed and the node is disconnected. Unfortunately
this is not a complete solution since it only works for published connections.
Connections that are unpublished ie. for discovery can indefinitely hang since we
never invoke their handers when we get a failure while a user is waiting for
the response. This change adds connection tracking to TcpTransport that ensures
we are notifying the corresponding connection if there is a failure on a channel.
Get mappings HEAD requests incorrectly return a content-length header of
0. This commit addresses this by removing the special handling for get
mappings HEAD requests, and just relying on the general mechanism that
exists for handling HEAD requests in the REST layer.
Relates #23192
Today when an exception is thrown handling a HEAD request, the body is
swallowed before the channel has a chance to see it. Yet, the channel is
where we compute the content length that would be returned as a header
in the response. This is a violation of the HTTP specification. This
commit addresses the issue. To address this issue, we remove the special
handling in bytes rest response for HEAD requests when an exception is
thrown. Instead, we let the upstream channel handle the special case, as
we already do today for the non-exceptional case.
Relates #25172
Previously the HEAD and GET aliases endpoints were misaigned in
behavior. The HEAD verb would 404 if any aliases are missing while the
GET verb would not if any aliases existed. When HEAD was aligned with
GET, this broke the previous usage of HEAD to serve as an existence
check for aliases. It is the behavior of GET that is problematic here
though, if any alias is missing the request should 404. This commit
addresses this by modifying the behavior of GET to behave in this
way. This fixes the behavior for HEAD to also 404 when aliases are
missing.
Relates #25043
Shared settings were added intially to allow the few common settings
names across aws plugins. However, in 6.0 these settings have been
removed. The last use was in netty, but since 6.0 also has the netty 3
modules removed, there is no longer a need for the shared property. This
commit removes the shared setting property.
This commit renames all rest test files to use the .yml extension
instead of .yaml. This way the extension used within all of
elasticsearch for yaml is consistent.
Netty removed a logging guarded we added to prevent a scary logging
message. We added a hack to work around this. They've added the guard
back, so we can remove the hack now.
Today we prune transport handlers in TransportService when a node is disconnected.
This can cause connections to starve in the TransportService if the connection is
opened as a short living connection ie. without sharing the connection to a node
via registering in the transport itself. This change now moves to pruning based
on the connections cache key to ensure we notify handlers as soon as the connection
is closed for all connections not just for registered connections.
Relates to #24632
Relates to #24575
Relates to #24557
In pre-release versions of Elasticsearch 5.0.0, users were subject to
log messages of the form "your platform does not.*reliably.*potential
system instability". This is because we disable Netty from being unsafe,
and Netty throws up this scary info-level message when unsafe is
unavailable, even if it was unavailable because the user requested that
it be unavailabe. Users were rightly confused, and concerned. So, we
contributed a guard to Netty to prevent this log message from showing up
when unsafe was explicitly disabled. This guard shipped with all
versions of Netty that shipped starting with Elasticsearch
5.0.0. Unfortunately, this guard was lost in an unrelated refactoring
and now with the 4.1.10.Final upgrade, users will again see this
message. This commit is a hack around this until we can get a fix
upstream again.
Relates #24469
Netty uses the number of processors for sizing various resources (e.g.,
thread pools, buffer pools, etc.). However, it uses the runtime number
of available processors which might not match the configured number of
processors as set in Elasticsearch to limit the number of threads (for
example, in Docker containers). A new feature was added to Netty that
enables configuring the number of processors Netty should see for sizing
this various resources. This commit takes advantage of this feature to
set this number of available processors to be equal to the configured
number of processors set in Elasticsearch.
Relates #24420
Tim Brooks
Ryan Ernst
Armin Braun
Jason Tedor
Daniel Mitterdorfer
Yannick Welsch
Simon Willnauer
Michael Basnight
Boaz Leskes