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Uwe Schindler commented on LUCENE-9432: --------------------------------------- Hi, the problematic part with linked list is two-kind: - there is an index-based access to the list. This should be removed and changed to getLast() or getFirst(), because index-based accesses in LinkedLists always have a linear scan. If this is not a big slowdown here, it looks like the list is small and does not grow much. In that case I tend to initialize the ArrayList with a larger size - LinkedList has a large object allocation and maintenance overhead (one small object for every entry), while arrays or ArrayLists are a block, which is also cache-friendly. So, two suggestions: - If LinkedList, then remove index-based access and replace by getLast() or getFirst() (if possible). If that's not possible its the completely wrong type of list - sorry. LinkedList also implements Deque, so lets use that interface as datatype in code! This also prevents us from accidentally using the index-based access: get(int) - If we use Deque, we can alternatively use ArrayDeque instead of LinkedList (it's just a replacement). Here we may think of a good initial size. Uwe > Use LinkedList instead of manual array re-sizing for better throughput. > ----------------------------------------------------------------------- > > Key: LUCENE-9432 > URL: https://issues.apache.org/jira/browse/LUCENE-9432 > Project: Lucene - Core > Issue Type: Improvement > Components: core/codecs > Reporter: Mohammad Sadiq > Priority: Minor > Labels: patch-available, performance, pull-request-available > Attachments: LUCENE-9432.patch > > > I observed that usingĀ {{LinkedList}} instead of manually re-sizing and > copying {{SegmentTermEnumFrame}}s improves red-line QPS. Does it make sense > to include this? -- 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