Hi,

 

Thanks for the hint to the issue! IMHO, the whole thing should be much easier 
now, as the whole infrastructure is already there: We have “DocValues as Stored 
Fields” available, so the functionality is available.

 

You can already use it, if your *disable* stored field flag on the ID field 
(because when stored field is missing, solr will use the docvalues field!). So 
I think the issue can be solved very easy by allowing to change the “preference 
order” (stored vs docvalues) per field/request type.

 

Uwe

 

-----

Uwe Schindler

Achterdiek 19, D-28357 Bremen

http://www.thetaphi.de <http://www.thetaphi.de/> 

eMail: [email protected]

 

From: David Smiley [mailto:[email protected]] 
Sent: Monday, June 5, 2017 3:04 PM
To: [email protected]
Subject: Re: Solr: by default use DocValues for ID fields?

 

There's already an issue: https://issues.apache.org/jira/browse/SOLR-5478

I've done custom adjustments for this for a couple of my clients already; it's 
on my long TODO list.  Feel free to carry the baton forward on this!

~ David

 

On Mon, Jun 5, 2017 at 8:42 AM Uwe Schindler <[email protected] 
<mailto:[email protected]> > wrote:

Hi,

I just noticed, when looking at some performance problems with distributed 
search using huge stored fields, that Solr by default fetches the Solr 
(external) ID when executing the first step of the search and then transmit 
those IDs to the node that executes the search. This requires that the whole 
stored field block is decompressed.

I just enabled DocValues and disabled stored fields and distributed search (the 
first part) was much faster, because the IDs were available asap. I also 
noticed that enabling only docvalues but not disabling the stored flag of the 
ID field did not help (as the stored field is preferred). Wouldn't it be a good 
idea to prefer an existent docvalues field for distributed/cloud search when 
doing the first search step (collecting IDs only)? I'd also suggest to enable 
docvalues for the ID field by default.

At least the 6.5.1 version of Solr does not have this by default. Maybe that’s 
a good change for Master/7.0.

Uwe

-----
Uwe Schindler
Achterdiek 19, D-28357 Bremen
http://www.thetaphi.de
eMail: [email protected] <mailto:[email protected]> 



---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected] 
<mailto:[email protected]> 
For additional commands, e-mail: [email protected] 
<mailto:[email protected]> 

-- 

Lucene/Solr Search Committer, Consultant, Developer, Author, Speaker

LinkedIn: http://linkedin.com/in/davidwsmiley | Book: 
http://www.solrenterprisesearchserver.com

Reply via email to