Transport connections between nodes remain in place until one or other
node shuts down or the connection is disrupted by a flaky network.
Today it is very difficult to demonstrate that transient failures and
cluster instability are caused by the network even though this is often
the case. In particular, transport connections open and close without
logging anything, even at `DEBUG` level, making it very hard to quantify
the scale of the problem or to correlate the networking problems with
external events.
This commit adds the missing `DEBUG`-level logging when transport
connections open and close, and also tracks the total number of
transport connections a node has opened as a measure of the stability of
the underlying network.
Today `GET _nodes/stats/fs` includes `{least,most}_usage_estimate`
fields for some nodes. These fields have rather strange semantics. They
are only reported on the elected master and on nodes that have been the
elected master since they were last restarted; when a node stops being
the elected master these stats remain in place but we stop updating them
so they may become arbitrarily stale.
This means that these statistics are pretty meaningless and impossible
to use correctly. Even if they were kept up to date they're never
reported for data-only nodes anyway, despite the fact that data nodes
are the ones where we care most about disk usage. The information needed
to compute the path with the least/most available space is already
provided in the rest the stats output, so we can treat the inclusion of
these stats as a bug and fix it by simply removing them in this commit.
Since these stats were always optional and mostly omitted (for opaque
reasons) this is not considered a breaking change.
Today the disk-based shard allocator accounts for incoming shards by
subtracting the estimated size of the incoming shard from the free space on the
node. This is an overly conservative estimate if the incoming shard has almost
finished its recovery since in that case it is already consuming most of the
disk space it needs.
This change adds to the shard stats a measure of how much larger each store is
expected to grow, computed from the ongoing recovery, and uses this to account
for the disk usage of incoming shards more accurately.
Backport of #58029 to 7.x
* Picky picky
* Missing type
Documents missing data types for several response parameters returned
by the node stats API.
Also adds several missing human-readable parameters returned by the API.
elastic/docs#1687 added support for the `[%collapsible]` Asciidoc
attribute, which creates collapsible sections in the HTML output.
This PR makes two related changes to the nodes stats API documentation:
* Makes the response parameter sections collapsible. This allows users
to more easily navigate the page without long walls of text.
* Reorders the response parameter sections to match the default order
returned by the API.
Relates to #47524.
* [DOCS] Document JVM node stats
Documents the `jvm` parameters returned by the `_nodes/stats` API.
Co-Authored-By: James Baiera <james.baiera@gmail.com>
Several files in the REST APIs nav section are included using
:leveloffset: tags. This increments headings (h2 -> h3, h3 -> h4, etc.)
in those files and removes the :leveloffset: tags.
Other supporting changes:
* Alphabetizes top-level REST API nav items.
* Change 'indices APIs' heading to 'index APIs.'
* Changes 'Snapshot lifecycle management' heading to sentence case.
The suggest stats were folded into the search stats as part of the
indices stats API in 5.0.0. However, the suggest metric remained as a
synonym for the search metric for BWC reasons. This commit deprecates
usage of the suggest metric on the indices stats API.
Similarly, due to the changes to fold the suggest stats into the search
stats, requesting the suggest index metric on the indices metric on the
nodes stats API has produced an empty object as the response since
5.0.0. This commit deprecates this index metric on the indices metric on
the nodes stats API.
The node stats API enables filtlering the top-level stats for only
desired top-level stats. Yet, this was never enabled for adaptive
replica selection stats. This commit enables this. We also add setting
these stats on the request builder, and fix an inconsistent name in a
setter.
Relates #28721
This change adds cgroup memory usage/limit to the OS stats section of
the node stats on Linux. This information is useful because in Docker
containers the standard node stats report the host memory limit, not
taking account of extra restrictions that may have been applied to the
container.
The original idea was to store these values as Long, truncating any values
outside the range of long. However, this meant that in the relatively common
case of no limit being applied, users would not see the same value in the OS
stats as they see by querying Linux directly. So instead the values are stored
as String. This change places a burden on consumers of the strings to
convert the strings to numbers and decide what to do about extremely large
values, but there will be very few consumers and they would need to have a
policy for dealing with "no limit" in any case.
This commit fixes a silly doc bug where the field that represents the
total CPU time consumed by all tasks in the same cgroup was mistakenly
reported as "usage" instead of "usage_nanos".
Relates #21029
Today when parsing a stats request, Elasticsearch silently ignores
incorrect metrics. This commit removes lenient parsing of stats requests
for the nodes stats and indices stats APIs.
Relates #21417
On some systems, cgroups will be available but not configured. And in
some cases, cgroups will be configured, but not for the subsystems that
we are expecting (e.g., cpu and cpuacct). This commit strengthens the
handling of cgroup stats on such systems.
Relates #21094
This commit adds a variety of real disk metrics for the block devices
that back Elasticsearch data paths. A collection of statistics are read
from /proc/diskstats and are used to report the raw metrics for
operations and read/write bytes.
Relates #15915
The ingest stats include the following statistics:
* `ingest.total.count`- The total number of document ingested during the lifetime of this node
* `ingest.total.time_in_millis` - The total time spent on ingest preprocessing documents during the lifetime of this node
* `ingest.total.current` - The total number of documents currently being ingested.
* `ingest.total.failed` - The total number ingest preprocessing operations failed during the lifetime of this node
Also these stats are returned on a per pipeline basis.
This commit modifies the load_average in the node stats API response
to be an object containing the one-minute, five-minute and
fifteen-minute load averages as fields (if those values are
available). Additionally, this commit modifies the cat nodes API
response to format the one-minute, five-minute and fifteen-minute load
averages as null if any of the respective values are not available.
Tim Brooks
David Turner
Lisa Cawley
James Rodewig
István Zoltán Szabó
Jason Tedor
Josh Soref
David Roberts
Peter Dyson
Clinton Gormley
Martijn van Groningen
xuzha
Tanguy Leroux