This refcounting doesn't work for shadow replicas since we open
the same translog file from more than one node while running a rolling
restart. This functionality is also superseeded by our filesystem abstraction
which detects file leaks under the hood.
Today, we rely on the user to set request listener threads to true when they are on the client side in order not to block the IO threads on heavy operations. This proves to be very trappy for users, and end up creating problems that are very hard to debug.
Instead, we can do the right thing, and automatically thread listeners that are used from the client when the client is a node client or a transport client.
This change also removes the ability to set request level listener threading, in the effort of simplifying the code path and reasoning around when something is threaded and when it is not.
closes#10940
This removes Elasticsearch's filter cache and uses Lucene's instead. It has some
implications:
- custom cache keys (`_cache_key`) are unsupported
- decisions are made internally and can't be overridden by users ('_cache`)
- not only filters can be cached but also all queries that do not need scores
- parent/child queries can now be cached, however cached entries are only
valid for the current top-level reader so in practice it will likely only
be used on read-only indices
- the cache deduplicates filters, which plays nicer with large keys (eg. `terms`)
- better stats: we already had ram usage and evictions, but now also hit count,
miss count, lookup count, number of cached doc id sets and current number of
doc id sets in the cache
- dynamically changing the filter cache size is not supported anymore
Internally, an important change is that it removes the NoCacheFilter infrastructure
in favour of making Query.rewrite specializing the query for the current reader so
that it will only be cached on this reader (look for IndexCacheableQuery).
Note that consuming filters with the query API (createWeight/scorer) instead of
the filter API (getDocIdSet) is important for parent/child queries because
otherwise a QueryWrapperFilter(ParentQuery) would run the wrapped query per
segment while relations might be cross segments.
The main `elasticsearch.yml` file mixed configuration, documentation
and advice together.
Due to a much improved documentation at <http://www.elastic.co/guide/>,
the content has been trimmed, and only the essential settings have
been left, to prevent the urge to excessive over-configuration.
Related: 8d0f1a7d123f579fc772e82ef6b9aae08f6d13fd
Expose new span queries from https://issues.apache.org/jira/browse/LUCENE-6083
Within returns matches from 'little' that are enclosed inside of a match from 'big'.
Containing returns matches from 'big' that enclose matches from 'little'.
Added infrastructure to allow basic member methods in the expressions
language to be called. The methods must have a signature with no arguments. Also
added the following member methods for date fields (and it should be easy to add more)
* getYear
* getMonth
* getDayOfMonth
* getHourOfDay
* getMinutes
* getSeconds
Allow fields to be accessed without using the member variable [value].
(Note that both ways can be used to access fields for back-compat.)
closes#10890
Using files that must be specified on each node is an anti-pattern
from the API based goal of ES. This change removes the ability
to specify the default mapping with a file on each node.
closes#10620
In order to safely complete recoveries / relocations we have to keep all operation done since the recovery start at available for replay. At the moment we do so by preventing the engine from flushing and thus making sure that the operations are kept in the translog. A side effect of this is that the translog keeps on growing until the recovery is done. This is not a problem as we do need these operations but if the another recovery starts concurrently it may have an unneededly long translog to replay. Also, if we shutdown the engine for some reason at this point (like when a node is restarted) we have to recover a long translog when we come back.
To void this, the translog is changed to be based on multiple files instead of a single one. This allows recoveries to keep hold to the files they need while allowing the engine to flush and do a lucene commit (which will create a new translog files bellow the hood).
Change highlights:
- Refactor Translog file management to allow for multiple files.
- Translog maintains a list of referenced files, both by outstanding recoveries and files containing operations not yet committed to Lucene.
- A new Translog.View concept is introduced, allowing recoveries to get a reference to all currently uncommitted translog files plus all future translog files created until the view is closed. They can use this view to iterate over operations.
- Recovery phase3 is removed. That phase was replaying operations while preventing new writes to the engine. This is unneeded as standard indexing also send all operations from the start of the recovery to the recovering shard. Replay all ops in the view acquired in recovery start is enough to guarantee no operation is lost.
- IndexShard now creates the translog together with the engine. The translog is closed by the engine on close. ShadowIndexShards do not open the translog.
- Moved the ownership of translog fsyncing to the translog it self, changing the responsible setting to `index.translog.sync_interval` (was `index.gateway.local.sync`)
Closes#10624
Only parent filters should use bitset filter cache, to avoid memory being wasted.
Also in case of object fields inline the field name into the nested object,
instead of creating an additional (dummy) nested identity.
Closes#10662Closes#10629
The assumption is that gaps in histogram are generally undesirable, for instance
if you want to build a visualization from it. Additionally, we are building new
aggregations that require that there are no gaps to work correctly (eg.
derivatives).