lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Dror Matalon <>
Subject Re: disable locks on read only indexes (performance improvement?)
Date Mon, 01 Dec 2003 21:58:23 GMT
On Mon, Dec 01, 2003 at 01:38:48PM -0800, Kevin A. Burton wrote:
> Would there be any performance improvement in query throughput and 
> latency if locking were disabled for readonly indexes?
> It doesnt' seem like it makes sense to worry about locking if you know 
> for SURE that the index will NEVER be updated again. 
> I'm noticing this problem now.  We are running a live indexer which does 
> a commit every N documents (right now 100,000) and then swaps the new 
> index into the system live.  This index is never again updated and we 
> use a multisearcher.  We then do index merges after a while into new 
> indexes to keep performance high and reduce the number of indexes.

Sounds quite familiar. One question though, when you say "swaps" the new
index, what do you mean? It's one area where locking might matter. If
you just use a multisearcher and add the new index I'm guessing that it
should work fine.

> I would assume that removing this lock could increase performance 
> especially to allow multiple concurrent searches on the same data.

There was talk about providing that in an upcoming version. Until then
you can try RODirectory:



> Kevin
> -- 
>    NewsMonster -
> Kevin A. Burton, Location - San Francisco, CA, Cell - 415.595.9965
>       AIM - sfburtonator,  Web -
> GPG fingerprint: 4D20 40A0 C734 307E C7B4  DCAA 0303 3AC5 BD9D 7C4D
>  IRC - #infoanarchy | #p2p-hackers | #newsmonster
> ---------------------------------------------------------------------
> To unsubscribe, e-mail:
> For additional commands, e-mail:

Dror Matalon
Zapatec Inc 
1700 MLK Way
Berkeley, CA 94709

To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message