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From Joan Touzet <>
Subject Re: High CPU usage caused by clustering and/or replication?
Date Fri, 09 Sep 2016 11:10:35 GMT
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,

----- Original Message -----
> From: "Joey Samonte" <>
> To:
> 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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