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From Hajiz <amirhos.ha...@gmail.com>
Subject Re: Clarification about segments
Date Mon, 14 Sep 2009 12:14:46 GMT

Hi all,

I'm new to Lucene and to this forum too. I'm a little confused about commit
and flush concepts in Lucene. You said that after we call "commit" the
documents/segments in RAM will be wrote in disk(directory). So what is
"minMergeDocs" factor? What does it mean?

In another way, I can ask my question like this: In which conditions will
Lucene write in-memory(cached) documents into directory?

Thanks in advance.



David Lee-26 wrote:
> 
> ok, thanks. I knew that the documents were buffered in memory until they
> were flushed, but I thought that in memory, they were still separate
> documents/segments until they were merged together at the appropriate time
> (dependent on the mergeFactor).
> 
> Do you mean that when the IndexWriter flushes the documents in memory to
> the
> disk, it will merge all the documents in that flush to one segment?
> 
> Thanks!
> David
> 
> On Sat, Aug 23, 2008 at 2:40 AM, Karsten F.
> <karsten-lucene@fiz-technik.de>wrote:
> 
>>
>> Hi David,
>>
>> this is not true, please take a look to
>> IndexWriter#setRAMBufferSizeMB
>> and
>> IndexWriter#setMaxBufferedDocs
>>
>> But you can produce 9 segments (each with only one document), if you call
>> IndexWriter#flush
>> or
>> IndexWriter#commit
>> after each addDocument
>>
>> so from my knowledge about lucene there is no difference between
>> #flush
>> and
>> #optimize(getMergeFactor())
>> (btw #optimize() is equal to optimize(1) ).
>>
>>
>> Best regards
>>  Karsten
>>
>> p.s. and yes, searching goes through every segment.
>>
>>
>> David Lee-26 wrote:
>> >
>> > So from what I understand, is it true that if mergeFactor is 10, then
>> when
>> > I
>> > index my first 9 documents, I have 9 separate segments, each containing
>> 1
>> > document? And when searching, it will search through every segment?
>> >
>> > Thanks!
>> > David
>> >
>> >
>>
>> --
>> View this message in context:
>> http://www.nabble.com/Clarification-about-segments-tp19117115p19120086.html
>> Sent from the Lucene - Java Users mailing list archive at Nabble.com.
>>
>>
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>>
> 
> 

-- 
View this message in context: http://www.nabble.com/Clarification-about-segments-tp19117115p25434739.html
Sent from the Lucene - Java Users mailing list archive at Nabble.com.


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