lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From petite_abeille <>
Subject Re: FileNotFoundException: Too many open files
Date Fri, 03 May 2002 09:49:41 GMT
On Wednesday, May 1, 2002, at 10:16 PM, Dmitry Serebrennikov wrote:

> "Less then a hundred" is definetely too many files for a Lucene index, 
> unless you have a very large number of stored fields!

Since changing indexing strategy, I have between 12 to 20 files per 
index (including deletable and segments).

> An optimized index should have about a dozen.

That what I see for small objects (eg with few fields).

>  So this either means that you have many stored fields

My "richest" object has around a dozen fields.

> or you are not calling optimize, or that, if you are, there are 
> unclosed IndexReader instances floating around that are still using 
> segments that existed before the optimization (which replaces all 
> segments with one new one).

I guess I have this part under control now.

> About file names:

Thanks for the explanation :-) I mostly have <n>.f<m> type files as one 
may expect.

> An index should have 2 + n *  (7 + m) files, where n is the number of 
> segments and m is the number of stored fields. For an optimized index 
> with one stored field this gives 10 files (not a 100!).

It seems that I'm getting there... ;-)

> So, unless IndexReaders are closed explicitly, this might explain why 
> an application runs fine under Windows, but has problems under OSX, or 
> whatever.

I decided to be much more "aggressive" with all the file handles... But 
I still rely heavely on the garbage collector as I'm using the reference 
api extensively... Seems to work fine so far...

> I agree that a desktop application should not require changes to system 
> configuration, but it might resonably expect a default value to be 
> present and it might change the soft limit (which is usually set very 
> low) in the startup script.

So far, my app seems to be doing fine without having to mess around with 
any system parameters... Also, it seems to be more responsive since I 
have more indexes... Go figure ;-)

> Good luck.



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

View raw message