On Tue, Jul 20, 2010 at 4:21 PM, Jason Rutherglen <jason.rutherg...@gmail.com> wrote: >> Right, much less GC if app frequently reopens. But a 32X increase in >> RAM usage is not trivial; I think we shouldn't enable it by default? > > Right, the RAM usage is quite high! Is there a more compact > representation we could use? Ah well, either way for good RT > performance, there are some users who may want to use this option.
Well, packed ints are more compact, but the decode cost would probably be catastrophic :) Maybe you could also use a smaller type (byte[], short[]) for sequence ids, but, you'd then have to handle wraparound/overflow. (In fact even w/ int[] you have to handle wraparound? long[] is probably safe :) ) EG on overflow, you'd have to allocate all new (zero'd) arrays for the next re-opened reader? >> Have you tested? > > The test would be a basic benchmark of queries against BV vs. an int[] > of deletes? Yes, in a normal reader (ie, not testing NRT -- just testing cost of applying deletes via int cmp instead of BV lookup). Mike --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org
