I would recommend that you try and reproduce the scenario you're running into with a Linux-based cluster, and if you find it there as well, file a bug with us so we can try and work your problem out.
If the problem goes away, then yes, I recommend for now you consider a Linux cluster. ;) I also recommend you use a minimum of 3 nodes for a cluster of q=8 (the default). ----- Original Message ----- > From: "Joey Samonte" <csharpdevelo...@hotmail.com> > To: dev@couchdb.apache.org, "Joan Touzet" <woh...@apache.org> > Sent: Wednesday, September 14, 2016 12:04:04 AM > Subject: Re: High CPU usage caused by clustering and/or replication? > > I actually stopped all replications and the high CPU occurs on the > 2nd node. I have only 2 nodes in the cluster. > > We really want to move to CouchDB 2.0, but we can't afford this issue > I am encountering. > > Do you suggest we just use Linux-based cluster? :( > > > > ________________________________ > From: Joan Touzet <woh...@apache.org> > Sent: Wednesday, September 14, 2016 3:47 AM > To: dev@couchdb.apache.org > Subject: Re: High CPU usage caused by clustering and/or replication? > > Joey, > > I'm sorry, I can't reproduce this problem. If you're able to provide > sample data that causes this issue, I'd be pleased to test (on a > non-virtualized Windows machine) with that. > > I will note that I am only testing with a local single CouchDB > server, > not in a cluster. What if you try replicating to a non-clustered > Windows server? We have absolutely zero testing done on CouchDB > clustered on Windows, and in fact really should declare our support > for > that configuration as beta. I will state I have not set up a local > Windows-based cluster (on separate Windows machines; I have run a 3 > node-on-1-server development cluster setup) so I can't guarantee that > this isn't the problem. > > Please note this Known Issue in CouchDB 2.0: > https://issues.apache.org/jira/browse/COUCHDB-2980 > > To quote our Known Issues document: "for now, we recommend always > using > the URL format for both source and target specifications." > > Finally, you should know it was my decision to continue Windows > support > for CouchDB, as no one else was able to step up. I did so primarily > because, in my experience, we have developers who develop against a > local CouchDB instance on their Windows laptops, then move to a > Linux-hosted cluster for server use. I didn't expect people would be > trying to leverage the Windows port in a real server configuration. > > That's not to say we couldn't eventually support Windows in a server > cluster configuration as "out of beta," but it'll take more > experience > and more repeatable bugs at the very least - and active CouchDB > Windows > developers with performance tuning experience at best. > > -Joan > > ----- Original Message ----- > > From: "Joey Samonte" <csharpdevelo...@hotmail.com> > > To: dev@couchdb.apache.org, "Joan Touzet" <woh...@apache.org> > > Sent: Tuesday, September 13, 2016 10:53:18 PM > > Subject: Re: High CPU usage caused by clustering and/or > > replication? > > > > I have tried to stop all replications, then restarted CouchDB, but > > still having almost 100% CPU with erl.exe > > > > > > ________________________________ > > From: Joan Touzet <woh...@apache.org> > > Sent: Friday, September 9, 2016 8:11 PM > > To: dev@couchdb.apache.org > > Subject: Re: High CPU usage caused by clustering and/or > > replication? > > > > 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" <csharpdevelo...@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: woh...@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" <csharpdevelo...@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. > > > > > > > > > > >
