Today, when listing thread pools via the cat thread pool API, thread
pools are listed in a column-delimited format. This is unfriendly to
command-line tools, and inconsistent with other cat APIs. Instead,
thread pools should be listed in a row-delimited format.
Additionally, the cat thread pool API is limited to a fixed list of
thread pools that excludes certain built-in thread pools as well as all
custom thread pools. These thread pools should be available via the cat
thread pool API.
This commit improves the cat thread pool API by listing all thread pools
(built-in or custom), and by listing them in a row-delimited
format. Finally, for each node, the output thread pools are sorted by
thread pool name.
Relates #19721
Warmers are now barely useful and will be removed in 3.0. Note that this only
removes the warmer API and query-based warmers. We still have warmers internally
for eg. global ordinals.
Close#15607
This adds an API for force merging lucene segments. The `/_optimize` API is now
deprecated and replaced by the `/_forcemerge` API, which has all the same flags
and action, just a different name.
Today, Elasticsearch has a separate merge thread pool checking once
per second (by default) if any merges are necessary, but this is no
longer necessary since we can and do now tell Lucene's
ConcurrentMergeScheduler never to "hard pause" threads when merges
fall behind, since we do our own index throttling.
This change goes back to letting Lucene launch merges as needed, and
removes these two expert settings:
index.merge.force_async_merge
index.merge.async_interval
Now merges kick off immediately instead of waiting up to 1 second
before running.
Closes#8643
By default active, rejected and queue thread statistics are included for the index, bulk and search thread pool.
Other thread statistics of other thread pools can be included via the `h` query string parameter.
Closes#4907
Jason Tedor
Martijn van Groningen
Adrien Grand
Lee Hinman
Clinton Gormley
Michael McCandless
Chris Earle
Luca Cavanna