This commit actually bounds the size of the generic thread pool. The
generic thread pool was of type cached, a thread pool with an unbounded
number of workers and an unbounded work queue. With this commit, the
generic thread pool is now of type scaling. As such, the cached thread
pool type has been removed. By default, the generic thread pool is
constructed with a core pool size of four, a max pool size of 128 and
idle workers can be reaped after a keep-alive time of thirty seconds
expires. The work queue for this thread pool remains unbounded.
With this commit we limit the size of all in-flight requests on
transport level. The size is guarded by a circuit breaker and is
based on the content size of each request.
By default we use 100% of available heap meaning that the parent
circuit breaker will limit the maximum available size. This value
can be changed by adjusting the setting
network.breaker.inflight_requests.limit
Relates #16011
This commit adds a new configuration file jvm.options to centralize and
simplify management of JVM options. This separates the configuration of
the JVM from the packaging scripts (bin/elasticsearch*, bin/service.bat,
and init.d/elasticsearch) simplifying end-user operational management of
custom JVM options.
We currently have a `discovery.zen.master_election.filter_client` setting that control whether their ping responses are ignored for master election (which is the current default). With the push to treat client nodes as normal nodes (and promote the transport/rest clients for client work), this should be changed. This commit remove this setting and it's companion `discovery.zen.master_election.filter_data` setting (currently defaulting to false) in favor of singe `discovery.zen.master_election.ignore_non_master_pings` setting with more intuitive name (defaulting to false).
Resolves#17325Closes#17329
In #17198, we removed suggest transport action, which
used the `suggest` threadpool to execute requests. Now
`suggest` threadpool is unused and suggest requests are
executed on the `search` threadpool.
Today, certain bootstrap properties are set and read via system
properties. This action-at-distance way of managing these properties is
rather confusing, and completely unnecessary. But another problem exists
with setting these as system properties. Namely, these system properties
are interpreted as Elasticsearch settings, not all of which are
registered. This leads to Elasticsearch failing to startup if any of
these special properties are set. Instead, these properties should be
kept as local as possible, and passed around as method parameters where
needed. This eliminates the action-at-distance way of handling these
properties, and eliminates the need to register these non-setting
properties. This commit does exactly that.
Additionally, today we use the "-D" command line flag to set the
properties, but this is confusing because "-D" is a special flag to the
JVM for setting system properties. This creates confusion because some
"-D" properties should be passed via arguments to the JVM (so via
ES_JAVA_OPTS), and some should be passed as arguments to
Elasticsearch. This commit changes the "-D" flag for Elasticsearch
settings to "-E".
Currently we suggesting users create a Node (using NodeBuilder in 2.x) to have a client that is capable of keeping up-to-date information. This is generally a bad idea as it means elasticsearch has no control over eg max heap size or gc settings, and is also problematic for users because they must deal with dependency collisions (and in 2.x+ dependencies of elasticsearch itself).
A better alternative, and what we should document, is to run a local elasticsearch server using bin/elasticsearch, and then use the transport client to connect to that local node. This local connection is virtually free, and allows the client code to be completely isolated from the elasticsearch process. Plugins are then also easy to deal with: just install them in elasticsearch as usual.
Related to #16679
2.x has show so far that running with security manager is the way to go.
This commit make this non-optional. Users that need to pass their own rules
can still do this via the system configuration for the security manager. They
can even opt out of all security that way.
This setting was missing from the docs, so I added it. However, I also
completely rewrote the nodes documentation page because it was mostly
talking about client nodes with some issues, without ever discussing
master nodes, or even tribe nodes. All nodes should be listed on a
"nodes" documentation page.
Fixes#15903Fixed#14429