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From Joan Touzet <woh...@apache.org>
Subject Re: High CPU usage caused by clustering and/or replication?
Date Fri, 09 Sep 2016 20:11:12 GMT
I don't know, a simple view with 100 documents should build quickly
unless your view code is unusual.

I would recommend replicating the database to a UNIX-based 2.0 cluster
to see if the problem is Windows-specific.

Sorry that I don't have any other ideas at the moment.

-Joan

----- Original Message -----
> From: "Joey Samonte" <csharpdeveloper@hotmail.com>
> To: dev@couchdb.apache.org
> Sent: Friday, September 9, 2016 3:08:37 PM
> Subject: RE: High CPU usage caused by clustering and/or replication?
> 
> Hi ma'am Joan,
>  
> But if the cause is a view being rebuilt, why is it so high? I only
> have less than 100 documents on that database which I wanted to test
> initially.
>  
> > Date: Fri, 9 Sep 2016 07:10:35 -0400
> > From: wohali@apache.org
> > To: dev@couchdb.apache.org
> > Subject: Re: High CPU usage caused by clustering and/or
> > replication?
> > 
> > Hi Joey,
> > 
> > I'm going to oversimplify a bit here to make the explanation
> > easier.
> > 
> > If you check the process manager/top on each node, do you see
> > couchjs
> > responsible for that 100% CPU?
> > 
> > Remember that views are not replicated, only documents. So if you
> > have
> > design documents that you replicated, those views may be being
> > rebuilt.
> > 
> > So-called "internal replication" will be placing segments of the
> > database
> > onto each node, and view building will be happening on each node as
> > well.
> > Since the view is also sharded, each shard of the database gets its
> > own
> > view shard; that has to be calculated independently on each node.
> > 
> > Even if you're not building views, remember that a cluster places
> > part
> > of the database on each node, spreading the load out as equally as
> > possible. In a standard 3-node cluster, each document write will be
> > written redundantly to every node, meaning CPU load will be
> > (mostly)
> > equal across all 3 nodes as you write that document.
> > 
> > Hope this helps,
> > Joan
> > 
> > 
> > ----- Original Message -----
> > > From: "Joey Samonte" <csharpdeveloper@hotmail.com>
> > > To: dev@couchdb.apache.org
> > > Sent: Thursday, September 8, 2016 11:30:46 PM
> > > Subject: High CPU usage caused by clustering and/or replication?
> > > 
> > > Good day,
> > >  
> > > I have setup a cluster with two nodes, and I am replicating the
> > > first
> > > node to an existing database through a loadbalancer. But I am
> > > getting a 100% CPU usage after a few minutes on both nodes. Is
> > > this
> > > an issue with RC4?
> > >  
> > > Thanks.
> > > 
> 

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