This commit improves the shard decision container class in the following
ways:
1. Renames UnassignedShardDecision to ShardAllocationDecision, so that
the class can be used for general shard decisions, not just unassigned
shard decisions.
2. Changes ShardAllocationDecision to have the final decision as a Type
instead of a Decision, because all the information needed from the final
decision is contained in `Type`.
3. Uses cached instances of ShardAllocationDecision for NO and THROTTLE
decisions when no explanation is needed (which is the common case when
executing reroute's as opposed to using the explain API).
Today SearchContext expose the current context as a thread local which makes any kind of sane interface design very very hard. This PR removes the thread local entirely and instead passes the relevant context anywhere needed. This simplifies state management dramatically and will allow for a much leaner SearchContext interface down the road.
As the wise man @ywelsch said: currently when we batch cluster state update tasks by the same executor, we the first task un-queued from the pending task queue. That means that other tasks for the same executor are left in the queue. When those are dequeued, they will trigger another run for the same executor. This can give unfair precedence to future tasks of the same executor, even if they weren't batched in the first run. Take this queue for example (all with equal priority)
```
T1 (executor 1)
T2 (executor 1)
T3 (executor 2)
T4 (executor 2)
T5 (executor 1)
T6 (executor 1)
```
If T1 & T2 are picked up first (when T5 & T6 are not yet queued), one would expect T3 & T4 to run second. However, since T2 is still in the queue, it will trigger execution of T5 & T6.
The fix is easy - ignore processed tasks when extracting them from the queue.
Closes#20768
Currently, update action delegates to index and delete actions
for replication using a dedicated transport action. This change
makes update a replication operation, removing the dedicated
transport action. This simplifies bulk execution and removes
duplicate logic for update retries and translation. This
consolidates the interface for single document write requests.
Now on the primary, the update request is translated to
an index or delete request before execution and the translated
request is sent to copies for replication.
Today it compiles when creating the aggregator, meaning that scripts will be
compiled as many times as there are buckets. Instead it should compile when
creating the factory so that scripts are compiled only once regardless of the
number of buckets.
TRA currently resolves incoming requests to IndexShards in order to acquire operations locks on them. There is no need for all subclasses to have to go through the same IndicesService/IndexService song and dance. Also, doing it once means we don't need to worry about edge cases where the shard is removed while a TRA is in flight.
This commit improves the logic flow of BalancedShardsAllocator in
preparation for separating out components of this class to be used
in the cluster allocation explain APIs. In particular, this commit:
1. Adds a minimum value for the index/shard balance factor settings (0.0)
2. Makes the Balancer data structures immutable and pre-calculated at
construction time.
3. Removes difficult to follow labeled blocks / GOTOs
4. Better logic for skipping over the same replica set when one of
the replicas received a NO decision
5. Separates the decision making logic for a single shard from the logic
to iterate over all unassigned shards.
Before this change the processing of the ranges in the date range (and
other range type) aggregations was done when the Aggregator was created.
This meant that the SearchContext did not know that now had been used in
a range until after the decision to cache was made.
This change moves the processing of the ranges to the aggregation builders
so that the search context is made aware that now has been used before
it decides if the request should be cached
This commit adds a did you mean feature to the strict REST params error
message. This works by comparing any unconsumed parameters to all of the
consumer parameters, comparing the Levenstein distance between those
parameters, and taking any consumed parameters that are close to an
unconsumed parameter as candiates for the did you mean.
* Fix pluralization in strict REST params message
This commit fixes the pluralization in the strict REST parameters error
message so that the word "parameter" is not unconditionally written as
"parameters" even when there is only one unrecognized parameter.
* Strength strict REST params did you mean test
This commit adds an unconsumed parameter that is too far from every
consumed parameter to have any candidate suggestions.
Relates #20747
This commit changes the strict REST parameters message to say that
unconsumed parameters are unrecognized rather than unused. Additionally,
the test is beefed up to include two unused parameters.
Relates #20745
Before this change the processing of the ranges in the date range (and
other range type) aggregations was done when the Aggregator was created.
This meant that the SearchContext did not know that now had been used in
a range until after the decision to cache was made.
This change moves the processing of the ranges to the aggregation builders
so that the search context is made aware that now has been used before
it decides if the request should be cached
This commit adds a did you mean feature to the strict REST params error
message. This works by comparing any unconsumed parameters to all of the
consumer parameters, comparing the Levenstein distance between those
parameters, and taking any consumed parameters that are close to an
unconsumed parameter as candiates for the did you mean.
* Fix pluralization in strict REST params message
This commit fixes the pluralization in the strict REST parameters error
message so that the word "parameter" is not unconditionally written as
"parameters" even when there is only one unrecognized parameter.
* Strength strict REST params did you mean test
This commit adds an unconsumed parameter that is too far from every
consumed parameter to have any candidate suggestions.
Relates #20747
This commit changes the strict REST parameters message to say that
unconsumed parameters are unrecognized rather than unused. Additionally,
the test is beefed up to include two unused parameters.
Relates #20745
Today when parsing a request, Elasticsearch silently ignores incorrect
(including parameters with typos) or unused parameters. This is bad as
it leads to requests having unintended behavior (e.g., if a user hits
the _analyze API and misspell the "tokenizer" then Elasticsearch will
just use the standard analyzer, completely against intentions).
This commit removes lenient URL parameter parsing. The strategy is
simple: when a request is handled and a parameter is touched, we mark it
as such. Before the request is actually executed, we check to ensure
that all parameters have been consumed. If there are remaining
parameters yet to be consumed, we fail the request with a list of the
unconsumed parameters. An exception has to be made for parameters that
format the response (as opposed to controlling the request); for this
case, handlers are able to provide a list of parameters that should be
excluded from tripping the unconsumed parameters check because those
parameters will be used in formatting the response.
Additionally, some inconsistencies between the parameters in the code
and in the docs are corrected.
Relates #20722
Today, the individual allocation deciders appear in random
order when initialized in AllocationDeciders, which means
potentially more performance intensive allocation deciders
could run before less expensive deciders. This adds to the
execution time when a less expensive decider could terminate
the decision making process early with a NO decision. This
commit orders the initialization of allocation deciders,
based on a general assessment of the big O runtime of each
decider, moving the likely more expensive deciders last.
Closes#12815
IndicesClusterStateService and IndicesStore are responsible for synchronizing local shard state based on incoming cluster state updates. On client/tribe nodes, which don't store any such shard/index data/metadata, all of the logic that computes which data is to be deleted, which shards to be initialized etc. can be completely skipped, saving precious CPU cycles.
CompositeIndicesRequest should be implemented by all requests that are composed of multiple subrequests which relate to one or more indices. A composite request is
executed by its own transport action class (e.g. TransportMultiSearchAction for _msearch), which goes through all the subrequests and delegates their execution to the appropriate transport action (e.g. TransportSearchAction for _msearch) for each single item. IndicesAliasesRequest is a particular request as it holds multiple items that implement AliasesRequest, but it shouldn't be considered a composite request, as it has no specific transport action for each of its items. Also, either all of its subitems fail or succeed.
Also clarified javadocs for CompositeIndicesRequest.
We have new icons for elastic products with 5.0. This change updates the
favicon embedded in elasticsearch that users see when using the rest api
through a browser.