You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@lucene.apache.org by "Uwe Schindler (Commented) (JIRA)" <ji...@apache.org> on 2012/02/14 08:45:00 UTC
[jira] [Commented] (LUCENE-2632) FilteringCodec, TeeCodec,
TeeDirectory
[ https://issues.apache.org/jira/browse/LUCENE-2632?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13207566#comment-13207566 ]
Uwe Schindler commented on LUCENE-2632:
---------------------------------------
Hey cool, sounds like this unmaintainable ParallelReaders obsolete by doing the splitting to several directories/parallel fields in the codec - so merging automtically works correct with every MP?
> FilteringCodec, TeeCodec, TeeDirectory
> --------------------------------------
>
> Key: LUCENE-2632
> URL: https://issues.apache.org/jira/browse/LUCENE-2632
> Project: Lucene - Java
> Issue Type: New Feature
> Components: core/index
> Affects Versions: 4.0
> Reporter: Andrzej Bialecki
> Attachments: LUCENE-2632.patch, LUCENE-2632.patch
>
>
> This issue adds two new Codec implementations:
> * TeeCodec: there have been attempts in the past to implement parallel writing to multiple indexes so that they are all synchronized. This was however complicated due to the complexity of IndexWriter/SegmentMerger logic. The solution presented here offers a similar functionality but working on a different level - as the name suggests, the TeeCodec duplicates index data into multiple output Directories.
> * TeeDirectory (used also in TeeCodec) is a simple abstraction to perform Directory operations on several directories in parallel (effectively mirroring their data). Optionally it's possible to specify a set of suffixes of files that should be mirrored so that non-matching files are skipped.
> * FilteringCodec is related in a remote way to the ideas of index pruning presented in LUCENE-1812 and the concept of tiered search. Since we can use TeeCodec to write to multiple output Directories in a synchronized way, we could also filter out or modify some of the data that is being written. The FilteringCodec provides this functionality, so that you can use like this:
> {code}
> IndexWriter --> TeeCodec
> | |
> | +--> StandardCodec --> Directory1
> +--> FilteringCodec --> StandardCodec --> Directory2
> {code}
> The end result of this chain is two indexes that are kept in sync - one is the full regular index, and the other one is a filtered index.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: dev-help@lucene.apache.org
Re: [jira] [Commented] (LUCENE-2632) FilteringCodec, TeeCodec, TeeDirectory
Posted by eks dev <ek...@yahoo.co.uk>.
cool indeed!
Now I can easily create full blown index on master and search (or
replicate) only a subset I need to search.
New use cases possible with this:
- Today one has to blow-up term directory with XXXMio unique ids
just to support deletions. Often a thing only needed during indexing.
For search only slaves, it is often sufficient to have uid as a stored
field (if at all), but term dictionary does not get bloated.
- possibility to simply store original documents in one index (kind of
key-value store) , but to search /distribute much smaller index. This
enables many new scenarios where Lucene takes storage responsibility
(Lucene overtakes Database role in many cases).
On Tue, Feb 14, 2012 at 8:45 AM, Uwe Schindler (Commented) (JIRA)
<ji...@apache.org> wrote:
>
> [ https://issues.apache.org/jira/browse/LUCENE-2632?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13207566#comment-13207566 ]
>
> Uwe Schindler commented on LUCENE-2632:
> ---------------------------------------
>
> Hey cool, sounds like this unmaintainable ParallelReaders obsolete by doing the splitting to several directories/parallel fields in the codec - so merging automtically works correct with every MP?
>
>> FilteringCodec, TeeCodec, TeeDirectory
>> --------------------------------------
>>
>> Key: LUCENE-2632
>> URL: https://issues.apache.org/jira/browse/LUCENE-2632
>> Project: Lucene - Java
>> Issue Type: New Feature
>> Components: core/index
>> Affects Versions: 4.0
>> Reporter: Andrzej Bialecki
>> Attachments: LUCENE-2632.patch, LUCENE-2632.patch
>>
>>
>> This issue adds two new Codec implementations:
>> * TeeCodec: there have been attempts in the past to implement parallel writing to multiple indexes so that they are all synchronized. This was however complicated due to the complexity of IndexWriter/SegmentMerger logic. The solution presented here offers a similar functionality but working on a different level - as the name suggests, the TeeCodec duplicates index data into multiple output Directories.
>> * TeeDirectory (used also in TeeCodec) is a simple abstraction to perform Directory operations on several directories in parallel (effectively mirroring their data). Optionally it's possible to specify a set of suffixes of files that should be mirrored so that non-matching files are skipped.
>> * FilteringCodec is related in a remote way to the ideas of index pruning presented in LUCENE-1812 and the concept of tiered search. Since we can use TeeCodec to write to multiple output Directories in a synchronized way, we could also filter out or modify some of the data that is being written. The FilteringCodec provides this functionality, so that you can use like this:
>> {code}
>> IndexWriter --> TeeCodec
>> | |
>> | +--> StandardCodec --> Directory1
>> +--> FilteringCodec --> StandardCodec --> Directory2
>> {code}
>> The end result of this chain is two indexes that are kept in sync - one is the full regular index, and the other one is a filtered index.
>
> --
> This message is automatically generated by JIRA.
> If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
> For more information on JIRA, see: http://www.atlassian.com/software/jira
>
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: dev-unsubscribe@lucene.apache.org
> For additional commands, e-mail: dev-help@lucene.apache.org
>
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: dev-help@lucene.apache.org