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Trejkaz commented on LUCENE-893: -------------------------------- Someone else on my team did some benchmarks for a query which was slow for us. We have a tree of items (one item per document), and given N items, we walk the path from the root to the item until finding an item with certain properties (expected average queries per item is around 3.) All the queries are against the same field (our unique ID field.) Timings of this process for 60,000 items: Buffer size Time 1024 1015s 2048 540s 4096 335s 8196 281s 16384 278s 32768 284s 65536 322s > Increase buffer sizes used during searching > ------------------------------------------- > > Key: LUCENE-893 > URL: https://issues.apache.org/jira/browse/LUCENE-893 > Project: Lucene - Java > Issue Type: Improvement > Components: Search > Affects Versions: 2.1 > Reporter: Michael McCandless > > Spinoff of LUCENE-888. > In LUCENE-888 we increased buffer sizes that impact indexing and found > substantial (10-18%) overall performance gains. > It's very likely that we can also gain some performance for searching > by increasing the read buffers in BufferedIndexInput used by > searching. > We need to test performance impact to verify and then pick a good > overall default buffer size, also being careful not to add too much > overall HEAP RAM usage because a potentially very large number of > BufferedIndexInput instances are created during searching > (# segments X # index files per segment). -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online. --------------------------------------------------------------------- To unsubscribe, e-mail: java-dev-unsubscr...@lucene.apache.org For additional commands, e-mail: java-dev-h...@lucene.apache.org