lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Zhang, Lisheng" <>
Subject RE: Upgrade lucene from 2.3.2 to 3.1.0
Date Mon, 14 Nov 2011 23:13:48 GMT
Thanks for your reply!

The reason why we cannot reuse IndexReader is that our server holds many (>4000)
independent index folders, each one corresponds to a separate URL. At any time
any folder can be queried, so we cannot hold all of them into memory.

In lucene 2.3.2 query is fast even if we recreate IndexSearcher (therefore Index-
Reader) each time. Yes I saw in source code even in 2.3.2 a lot of segement 
information also are loaded into memory, and in 3.1.0 there seems a lot of code 
changes in IndexReader initialization, so do we expect performance change if we 
keep our way?

Thanks very much for helps!

-----Original Message-----
From: Uwe Schindler []
Sent: Monday, November 14, 2011 2:29 PM
Subject: RE: Upgrade lucene from 2.3.2 to 3.1.0


> We plan to upgrade lucene from 2.3.2 to 3.1.0, from reading "Lucene In Action"
> I learned that we should "warm up" IndexSearcher and donot expect initial a
> few queries to be fast.

This was always the case, not only since Lucene 2.9/3.0. You should warm your searchers.

> But due to our special app we cannot "warm up" (each query has to use a new
> IndexSearcher), in lucene 2.3.2 this seems OK, Should we encounter obvious
> performance decrease in 3.1.0 if keeping this way?

This seems to be an XY problem. Why can you not reuse IndexReaders?


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

View raw message