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Posted to java-user@lucene.apache.org by "Sitowitz, Paul" <PS...@verisign.com> on 2012/08/22 19:31:34 UTC
Lucene Index backward compatibility related question
Hello,
I have two products that are using Lucene: The first product creates the Lucene indexes for some data using Lucene version 3.01. The second product utilizes the indexes created by the first product for text search purposes and is also using Lucene 3.01. I understand that the latest version of Lucene 4.0 has made several performance enhancements of which we would like to be able to leverage by our second product.
Question: If we upgrade the second product to use Lucene 4.0, will we still be able to take advantage of search related performance gains while still using the index created using Lucene 3.01 by our first product? OR, will we have to "bite the bullet" and upgrade BOTH products to use the latest version of Lucene?
Thanks in advance for you response.
Sincerely,
Paul Sitowitz
________________________________
P a u l S i t o w i t z
Core Engineering
VeriSign Naming Services
12061 Bluemont Way
Reston, VA 20190
psitowitz@verisign.com (email)
703-948-3298 (office)
703-626-3593 (mobile)
This message is intended for the use of the individual or entity to which it is addressed, and may contain information that is privileged, Confidential and exempt from disclosure under applicable law. Any unauthorized use, distribution, or disclosure is strictly prohibited. If you have received this message in error, please notify sender immediately and destroy/delete the original transmission
Re: Lucene Index backward compatibility related question
Posted by Michael McCandless <lu...@mikemccandless.com>.
Small correction here: you are able to "write" to a 3.x index using
4.0. It's just that the newly created segments will be written using
the Lucene4x codec.
Mike McCandless
http://blog.mikemccandless.com
On Mon, Aug 27, 2012 at 2:35 PM, Stephen Howe <si...@gmail.com> wrote:
> Paul,
>
> So long as you are not writing to the 3.x index, it appears Lucene 4.0 can
> read the indexes in a read only format. See Mike McCandle's blog post
> http://blog.mikemccandless.com/2012/07/lucene-400-alpha-at-long-last.html about
> the alpha release codecs. As to whether or not that codec allows you to
> leverage the Lucene 4.0 performance gains, I'll defer to someone wiser on
> the subject. I would imagine it does, but I'm not sure.
>
> Sincerely,
> Stephen
>
> On Wed, Aug 22, 2012 at 1:31 PM, Sitowitz, Paul <PS...@verisign.com>wrote:
>
>> Hello,
>>
>> I have two products that are using Lucene: The first product creates the
>> Lucene indexes for some data using Lucene version 3.01. The second product
>> utilizes the indexes created by the first product for text search purposes
>> and is also using Lucene 3.01. I understand that the latest version of
>> Lucene 4.0 has made several performance enhancements of which we would like
>> to be able to leverage by our second product.
>>
>> Question: If we upgrade the second product to use Lucene 4.0, will we
>> still be able to take advantage of search related performance gains while
>> still using the index created using Lucene 3.01 by our first product? OR,
>> will we have to "bite the bullet" and upgrade BOTH products to use the
>> latest version of Lucene?
>>
>> Thanks in advance for you response.
>>
>> Sincerely,
>>
>> Paul Sitowitz
>>
>>
>> ________________________________
>> P a u l S i t o w i t z
>> Core Engineering
>> VeriSign Naming Services
>>
>> 12061 Bluemont Way
>> Reston, VA 20190
>>
>> psitowitz@verisign.com (email)
>> 703-948-3298 (office)
>> 703-626-3593 (mobile)
>>
>> This message is intended for the use of the individual or entity to which
>> it is addressed, and may contain information that is privileged,
>> Confidential and exempt from disclosure under applicable law. Any
>> unauthorized use, distribution, or disclosure is strictly prohibited. If
>> you have received this message in error, please notify sender immediately
>> and destroy/delete the original transmission
>>
>>
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Re: Lucene Index backward compatibility related question
Posted by Stephen Howe <si...@gmail.com>.
Paul,
So long as you are not writing to the 3.x index, it appears Lucene 4.0 can
read the indexes in a read only format. See Mike McCandle's blog post
http://blog.mikemccandless.com/2012/07/lucene-400-alpha-at-long-last.html about
the alpha release codecs. As to whether or not that codec allows you to
leverage the Lucene 4.0 performance gains, I'll defer to someone wiser on
the subject. I would imagine it does, but I'm not sure.
Sincerely,
Stephen
On Wed, Aug 22, 2012 at 1:31 PM, Sitowitz, Paul <PS...@verisign.com>wrote:
> Hello,
>
> I have two products that are using Lucene: The first product creates the
> Lucene indexes for some data using Lucene version 3.01. The second product
> utilizes the indexes created by the first product for text search purposes
> and is also using Lucene 3.01. I understand that the latest version of
> Lucene 4.0 has made several performance enhancements of which we would like
> to be able to leverage by our second product.
>
> Question: If we upgrade the second product to use Lucene 4.0, will we
> still be able to take advantage of search related performance gains while
> still using the index created using Lucene 3.01 by our first product? OR,
> will we have to "bite the bullet" and upgrade BOTH products to use the
> latest version of Lucene?
>
> Thanks in advance for you response.
>
> Sincerely,
>
> Paul Sitowitz
>
>
> ________________________________
> P a u l S i t o w i t z
> Core Engineering
> VeriSign Naming Services
>
> 12061 Bluemont Way
> Reston, VA 20190
>
> psitowitz@verisign.com (email)
> 703-948-3298 (office)
> 703-626-3593 (mobile)
>
> This message is intended for the use of the individual or entity to which
> it is addressed, and may contain information that is privileged,
> Confidential and exempt from disclosure under applicable law. Any
> unauthorized use, distribution, or disclosure is strictly prohibited. If
> you have received this message in error, please notify sender immediately
> and destroy/delete the original transmission
>
>
Re: Lucene Index backward compatibility related question
Posted by Jack Krupansky <ja...@basetechnology.com>.
Technically, you should be able to use both 3.0 and 4.0 indexes in the same
app, but a recent inquiry here indicated some unresolved problem. Here's the
official statement from CHANGES.txt for 4.0-BETA:
" - On upgrading to 4.0, if you do not fully reindex your documents,
Lucene will emulate the new flex API on top of the old index,
incurring some performance cost (up to ~10% slowdown, typically).
To prevent this slowdown, use oal.index.IndexUpgrader
to upgrade your indexes to latest file format (LUCENE-3082).
Mixed flex/pre-flex indexes are perfectly fine -- the two
emulation layers (flex API on pre-flex index, and pre-flex API on
flex index) will remap the access as required. So on upgrading to
4.0 you can start indexing new documents into an existing index.
To get optimal performance, use oal.index.IndexUpgrader
to upgrade your indexes to latest file format (LUCENE-3082)."
Bottom line: Write a test and see for yourself.
-- Jack Krupansky
-----Original Message-----
From: Sitowitz, Paul
Sent: Wednesday, August 22, 2012 1:31 PM
To: java-user@lucene.apache.org
Cc: sitowitz@gmail.com
Subject: Lucene Index backward compatibility related question
Hello,
I have two products that are using Lucene: The first product creates the
Lucene indexes for some data using Lucene version 3.01. The second product
utilizes the indexes created by the first product for text search purposes
and is also using Lucene 3.01. I understand that the latest version of
Lucene 4.0 has made several performance enhancements of which we would like
to be able to leverage by our second product.
Question: If we upgrade the second product to use Lucene 4.0, will we
still be able to take advantage of search related performance gains while
still using the index created using Lucene 3.01 by our first product? OR,
will we have to "bite the bullet" and upgrade BOTH products to use the
latest version of Lucene?
Thanks in advance for you response.
Sincerely,
Paul Sitowitz
________________________________
P a u l S i t o w i t z
Core Engineering
VeriSign Naming Services
12061 Bluemont Way
Reston, VA 20190
psitowitz@verisign.com (email)
703-948-3298 (office)
703-626-3593 (mobile)
This message is intended for the use of the individual or entity to which it
is addressed, and may contain information that is privileged, Confidential
and exempt from disclosure under applicable law. Any unauthorized use,
distribution, or disclosure is strictly prohibited. If you have received
this message in error, please notify sender immediately and destroy/delete
the original transmission
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