On Sun, Jun 29, 2008 at 9:42 AM, Jason Rutherglen <[EMAIL PROTECTED]> wrote: > IndexReader.document as it is is really a lame duck. The > IndexReader.document call being synchronized at the top level drags down the > performance of systems that store data in Lucene. A single file descriptor > for all threads on an index that is constantly returning results with fields > is a serious problem. Users are always complaining about this issue and now > I know why.
Each part of the index (e.g. tis, frq) is actually only covered by a single file descriptor by default - stored fields aren't unique in that regard. It's probably the case that the stored fields of a given document are much less likely to be in OS cache though... and in that case having multiple requests in-flight to the disk could improve things. On anything except Windows, using pread may be the answer (after the other synchronization is also removed of course): https://issues.apache.org/jira/browse/LUCENE-753 -Yonik --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
