[svn.haxx.se] · SVN Dev · SVN Users · SVN Org · TSVN Dev · TSVN Users · Subclipse Dev · Subclipse Users · this month's index

Re: SQL indices a WC format bump and 1.7

From: Philip Martin <philip.martin_at_wandisco.com>
Date: Fri, 02 Sep 2011 17:35:42 +0100

Philip Martin <philip.martin_at_wandisco.com> writes:

> The query STMT_SELECT_NODE_CHILDREN_WALKER_INFO as used in 1.7
>
> SELECT local_relpath, op_depth, presence, kind
> FROM nodes
> WHERE wc_id = ?1 AND parent_relpath = ?2
> GROUP BY local_relpath
> ORDER BY op_depth DESC
>
> performs poorly and doesn't scale well with working copy size.

After some more discussion in IRC it seems that the above SQL is
dubious: the selected columns may not all come from the same row, and we
may not get the highest op_depth. Using NODES_CURRENT would fix the
problem as does my C solution, and the combination of the two is now on
trunk. So I'll be proposing r1164426 and r1164614 to fix the 1.7
performance problem without any schema changes.

-- 
uberSVN: Apache Subversion Made Easy
http://www.uberSVN.com
Received on 2011-09-02 18:36:19 CEST

This is an archived mail posted to the Subversion Dev mailing list.