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From Adam Kocoloski <kocol...@apache.org>
Subject Re: How to speedup view generation?
Date Thu, 04 Nov 2010 23:32:57 GMT
The view generation status updates ignore old MVCC versions completely.  We're a bit inconsistent
in that department - the replicator reports the current sequence number, but the view updater
reports the number of documents that have been loaded into memory so far.  As a result, I
wouldn't expect the number of    obsolete updates to affect the perceived view updater progress
much at all.  Best,

Adam

On Nov 4, 2010, at 5:27 PM, Randall Leeds wrote:

> I'm more interested to know if compacting the database before building
> the view helps.
> 
> If you have many document updates it could be that the density of new
> changes is higher at the end of the database file. In other words, the
> I/O bottleneck isn't caused by a large file but but maybe reading more
> information. Much of the early parts of the by-sequence btree may have
> been overwritten by new changes and therefore ignored in view
> generation.
> 
> For example, if you have a database of 1 document with 1 million
> changes, you would expect the view generation to roll through the
> first 999k changes very quickly.
> 
> -Randall
> 
> On Thu, Nov 4, 2010 at 04:07, cdr53x <cdr53x@free.fr> wrote:
>> On 11/04/2010 11:55 AM, Nils Breunese wrote:
>>> 
>>> Also after compaction?
>>> 
>> 
>> Yes after compaction. ;)
>> 
>> 
>> 
>> 
>> 
>> 


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