[
https://issues.apache.org/jira/browse/LUCENE-9996?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17365403#comment-17365403
]
ASF subversion and git services commented on LUCENE-9996:
---------------------------------------------------------
Commit e12bd964866348f95832a52c92fedb39ec500a90 in lucene-solr's branch
refs/heads/branch_8x from Adrien Grand
[ https://gitbox.apache.org/repos/asf?p=lucene-solr.git;h=e12bd96 ]
LUCENE-9996: Reduce RAM usage of DWPT for a single document. (#184)
With this change, doc-value terms dictionaries use a shared `ByteBlockPool`
across all fields, and points, binary doc values and doc-value ordinals use
slightly smaller page sizes.
> Can we improve DWPT's initial memory footprint?
> -----------------------------------------------
>
> Key: LUCENE-9996
> URL: https://issues.apache.org/jira/browse/LUCENE-9996
> Project: Lucene - Core
> Issue Type: Improvement
> Reporter: Adrien Grand
> Priority: Minor
> Time Spent: 0.5h
> Remaining Estimate: 0h
>
> Say you are indexing only keyword fields, that are both indexed and have doc
> values. The first document that gets added to a DWPT will increase memory
> usage by about 80kB per field. This is due mostly to:
> - the {{BytesRefHash}} for the inverted index, which allocates a 32kB page
> - the {{BytesRefHash}} for the doc values terms dict, which allocates
> another 32kB page
> - the {{SortedDocValuesWriter#pending}} buffer that allocates a long[1024]:
> 8kB
> So if you have 10 actively indexing indices that have 100 fields each and 24
> indexing threads, this gives a total of 10*100*24*80kB = 1.8GB. If you
> happened to give less than 1.8GB for your indexing buffers overall, Lucene
> will likely do very small flushes that have only a few documents, which
> in-turn will make indexing rather slow.
> Could we improve DWPT so that it more progressively reserves memory as more
> documents get added?
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org
For additional commands, e-mail: issues-h...@lucene.apache.org
