uschindler commented on code in PR #13570:
URL: https://github.com/apache/lucene/pull/13570#discussion_r1679741852
##########
lucene/core/src/java21/org/apache/lucene/store/MemorySegmentIndexInputProvider.java:
##########
@@ -125,4 +134,31 @@ private final MemorySegment[] map(
}
return segments;
}
+
+ public ConcurrentHashMap<String, RefCountedSharedArena> attachment() {
+ return new ConcurrentHashMap<>();
+ }
+
+ /**
+ * Gets an arena for the give path, potentially aggregating files from the
same segment into a
+ * single ref counted shared arena. A ref counted shared arena, if created
will be added to the
+ * given arenas map.
+ */
+ static Arena getSharedArena(Path p, ConcurrentHashMap<String,
RefCountedSharedArena> arenas) {
+ String filename = p.getFileName().toString();
+ String segmentName = IndexFileNames.parseSegmentName(filename);
+ if (filename.length() == segmentName.length()) {
+ // no segment found; just use a shared segment
+ return Arena.ofShared();
Review Comment:
The case you are looking here at is when there is no relationship to a
specific segment of an index. If it is a file which does not belong to a
segment it returns a new shared arena (fallback to default). For this case it
MUST return a new shared segment as the file belongs to nothing else and the
mmapped memory must be freed on close.
If the file belongs to an index segment it also creates a shared arena for
the first file, but other files belonging to same segment will increase
refcount. For that it has its own implementation of Arena which includes
refcounting.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
