[Ovirt-devel] [PATCH] Update search index every half hour.

[Jason Guiditta]

On Wed, 2009-01-21 at 16:09 -0500, Scott Seago wrote:
> Daniel P. Berrange wrote:
> > On Wed, Jan 21, 2009 at 07:24:27PM +0000, Scott Seago wrote:
> >   
> >> Sets up a cron job to update the search index every half hour.
> >>  With this in place it will be at most 30 minutes after new/
> >> updated content is generated before it will show up in search results.
> >>     
> >
> > 30 minutes seems like quite a long time.  Is there much CPU overhead
> > from updating the search index ?  If not I think it'd be nicer to
> > do it every 5 minutes or more frequently still. Shame it can't be
> > done "on demand" really - eg triggered when an indexable table is
> > updated - albeit it with a small delay, so if multiple updates arrive
> > in a short time it can coalleasce into one index update.
> >
> > Daniel
> >   
> 30 minutes was totally arbitrary. Overhead would depend mostly on how 
> much content we've got -- and for now, we don't have a huge quantity -- 
> just rows for VMs, storage volumes, hosts, and pools. 5 minutes is 
> probably fine -- in any case, there's probably not much point in going 
> longer than 5 minutes unless we have to.
> 
> Search index updates are triggered from outside the DB, so there isn't a 
> direct way of doing an on-demand update, although you could probably 
> simulate this with a daemon of some sort. There's already a db table 
> that gets rows added for objects that need to be updated. Index updates 
> (rather than the reindex operation) only work on objects with an update 
> -- so we could have a daemon that polled this table and forked a process 
> to do the update after it observed a new row added to this table -- but 
> with no new rows added after a set period of time.
> 
> On my dev server it takes about 3 seconds to run the update index rake 
> task when there's nothing to update -- so even running this task every 
> minute might not have much of an impact on performance.
> 
> Scott
> 
> _______________________________________________
> Ovirt-devel mailing list
> Ovirt-devel at redhat.com
> https://www.redhat.com/mailman/listinfo/ovirt-devel

ACK.  Other than the discussion about making this more frequent then
every half hour, works for me.