Jenn Turner | 26 May 17:02 2016
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[NEWS] The CouchDB weekly news for May 26 is out!

Hello there CouchDB fans!

The weekly news is now live at: http://blog.couchdb.org/2016/05/26/
couchdb-weekly-news-may-26-2016/

Highlights include discussion on replication, something funny about REST,
and use cases for both PouchDB and CouchDB!

Thanks go out to Joan Touzet for submitting content suggestions:)

You can help us spread the news by sharing on Twitter (
https://twitter.com/CouchDB/status/735847980641701888
<https://twitter.com/CouchDB>) and other social networks.

Also if you have news for next week, just REPLY to this thread!

Cheers!
Stefan du Fresne | 25 May 10:34 2016
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The state of filtered replication

Hello all,

I work on an app that involves a large amount of CouchDB filtered replication (every user has a filtered
subset of the DB locally via PouchDB). Currently filtered replication is our number 1 performance
bottleneck for rolling out to more users, and I'm trying to work out where we can go from here.

Our current setup is one CouchDB database and N PouchDB installations, which all two-way replicate, with
the CouchDB->PouchDB replication being filtered based on user permissions / relevance [1].

Our issue is that as we add users a) total document creation velocity increases, and b) the proportion of
documents that are relevant to any particular user decreases. These two points cause replication-- both
initial onboarding and continual-- to take longer and longer.

At this stage we are being forced to manually limit the number of users we onboard at any particular time to
half a dozen or so, or risk CouchDB being unresponsive [2]. As we'd want to be onboarding 50-100 at any
particular time due to how we're rolling pit, you can imagine that this is pretty painful.

I have already re-written the filter in Erlang, which halved its execution time, which is awesome!

I also attempted to simplify the filter to increase performance. However, filter speed seems more
dependent on the physical size of your filter as opposed to what code executes, which makes writing a
simple filter that can fall-back to a complicated filter not terribly useful (see:
https://issues.apache.org/jira/browse/COUCHDB-3021 <https://issues.apache.org/jira/browse/COUCHDB-3021>)

If the above linked ticket is fixed (if it can be) this would make our filter 3-4x faster again. However, this
still wouldn't address the fundamental issue that filtered replication is very CPU-intensive, and so as
noted above doesn't seem to scale terribly well.

Ideally then, I would like to remove filter replication completely, but there does not seem to be a good
alternative right now.
(Continue reading)

Jenn Turner | 19 May 20:05 2016

[NEWS] The CouchDB weekly news for May 19 is out!

Hello there CouchDB fans!

The weekly news is now live at: https://blog.couchdb.org/2016/05/19/couchdb-
weekly-news-may-19-2016/

Highlights include a style guide for Fauxton, the board report for this month,
and the burning question – Don’t you think CouchDB is underestimated?

Thanks go out to Robert Kowalski for submitting news tips :)

You can help us spread the news by sharing on Twitter
(https://twitter.com/CouchDB/status/733355811167174657) and other social
networks.  

Also **if you have news for next week**, just REPLY to this thread!

Cheers!  

Jenn Turner

The Neighbourhoodie Software GmbH  
Adalbertstr. 7-8, 10999 Berlin  
[neighbourhood.ie](http://neighbourhood.ie/ "http://neighbourhood.ie/" )  

Handelsregister HRB 157851 B Amtsgericht Charlottenburg  
Geschäftsführung: Jan Lehnardt

Oleg Cohen | 12 May 21:22 2016

Deletion of documents

Greetings,

I have a CouchDB 2.0 cluster. I notice when I delete documents, Fauxton displays a warning next to the # of
Docs. Here is an example of the warning: "This database has just 1 docs and 3 deleted docs”. What does it
mean and is this a problem?

Also, how do I remove deleted documents from the database? So far the only way I found is to run a _purge
command on each shard on each node in the cluster. Is this the correct way? Are there better ways to do it?

Thank you,
Oleg

Jenn Turner | 12 May 19:26 2016

[NEWS] The CouchDB weekly news for May 12 is out!

Hello, hello!

The weekly news is now live at: https://blog.couchdb.org/2016/05/12/couchdb-
weekly-news-may-12-2016/

Highlights include lots of great new releases, 2 blog posts from Glynn Bird,
plus a new tool from Dale Harvey. Thanks go out to Clemens Stolle for
submitting news tips :)

You can help us spread the news by sharing on Twitter
(https://twitter.com/CouchDB/status/730810218435772416) and other social
networks.  

Also if you have news for next week, just REPLY to this thread!

Cheers!  

Jenn Turner

The Neighbourhoodie Software GmbH  
Adalbertstr. 7-8, 10999 Berlin  
[neighbourhood.ie](http://neighbourhood.ie/ "http://neighbourhood.ie/" )  

Handelsregister HRB 157851 B Amtsgericht Charlottenburg  
Geschäftsführung: Jan Lehnardt

Oleg Cohen | 6 May 20:18 2016

CouchDB 2.0 cluster problem when first node is down

Greetings,

We ran into an issue when testing CouchDB 2.0 clustering. We ran a 2-node
cluster using the dev/run -n 2 command.

If we bring node2 down, all on node1 is still working fine. When we bring
down node1 using remsh and issuing init:stop(). command, the databases on
node2 are no longer readable.

We test this by trying to read the _users database using the following
command:

curl -X GET "http://127.0.0.1:25984/_users" --user admin:xxxxxxx

The get the following error:

{"error":"nodedown","reason":"progress not possible"}

If node1 is restarted, the problem goes away.

We experienced the same issue running a 3-node cluster across 3 different
servers.

Wondering if anyone ran into the same issue and if there is a workaround or
a way to fix the issue.

Thank you,
Oleg

--

-- 
(Continue reading)

Jason Winshell (Bear River | 5 May 18:32 2016

CouchDB 1.5 log rotation on Windows

I am using CouchDB 1.5.1. The couchdb.log is growing very large, even at INFO level. What is the best
mechanism to rotate/rolloff logs on Windows.

Thanks
Jason
Jenn Turner | 5 May 16:51 2016

[NEWS] The CouchDB weekly news for May is out!

Hi CouchDB fans! ![](images/composer-emoji/apple/1f44b.png)

The weekly news is now live at: https://blog.couchdb.org/2016/05/05/couchdb-
weekly-news-may-5-2016/

Highlights include lots of great new releases, including the return of
`pouchy`, plus a deep sea jellyfish!

You can help us spread the news by sharing on Twitter
(https://twitter.com/CouchDB/status/728234638888538112) and other social
networks.  

Also if you have news for next week, just REPLY to this thread!

  
Have a great rest of your week ![](images/composer-emoji/apple/263a.png)️️

Jenn Turner

The Neighbourhoodie Software GmbH  
Adalbertstr. 7-8, 10999 Berlin  
[neighbourhood.ie](http://neighbourhood.ie/ "http://neighbourhood.ie/" )  

Handelsregister HRB 157851 B Amtsgericht Charlottenburg  
Geschäftsführung: Jan Lehnardt

Diego . | 28 Apr 18:20 2016
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How can I unsubscribe?

How can I unsubscribe?

Thanks.
Jason Gordon | 28 Apr 16:04 2016

CouchDB 2.0 and zones

Hi,

Does CouchDB 2.0 support BigCouch-style zones?  If not, is it in the
roadmap?  I would like to have a cluster where two nodes are in one data
center and a third node (for hot failover) is in a remote data center.  I
know replication could be used  but a cluster with zones seems more elegant.

Thanks,

Jason
Christopher D. Malon | 28 Apr 00:59 2016
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connection timeouts and multitasking

Hi,

I'm running CouchDB 1.5.0 on a single-processor EC2 ubuntu (m3.medium)
instance.  A preforking web application that accesses the database runs
on the same server.

I am testing the system with a single user.  In most cases, the web application's process
waits for the CouchDB response before proceeding with any other activity.

Intermittently, some simple GET requests (record accesses, not view queries)
to CouchDB from the web app are timing out.  I'm nowhere near max_connections
or max_dbs_open yet.

Standard advice might be to put the DB and web app on separate servers,
but since this problem occurs already with a single user, I'm not confident
that would fix anything.  The only possibly nonstandard thing I'm doing is
aggressively issuing a view query with "stale=update_after" after every
record update to the database, and that reindexing might still be running when I
try to send another read request.

Have others experienced these kinds of timeouts, and should I respond by
increasing the number of CPU cores or offloading the DB from the server?

Thanks,
Christopher


Gmane