Hmph, that seems to be an oversight in the documentation! Here’s the set of 
performance-related configuration options that can be specified as top-level 
fields in the replication specification:

worker_batch_size
worker_processes
http_connections
connection_timeout
retries_per_request
socket_options
checkpoint_interval
use_checkpoints

These are all documented in the [replicator] section of the configuration docs, 
which is where you’d go to set the defaults for all replications mediated by 
that server:

http://docs.couchdb.org/en/stable/config/replicator.html#replicator 
<http://docs.couchdb.org/en/stable/config/replicator.html#replicator>

Configuring one of those fields in the replication doc will always override the 
default for the server. There are several other additional fields that are 
meaningful in a replication document — I haven’t checked to see if every one is 
documented. The code that validates them all is here:

https://github.com/apache/couchdb/blob/2.2.0/src/couch_replicator/src/couch_replicator_docs.erl#L469-L529
 
<https://github.com/apache/couchdb/blob/2.2.0/src/couch_replicator/src/couch_replicator_docs.erl#L469-L529>

Looks like we have a bit of homework to do here … Cheers,

Adam

> On Nov 6, 2018, at 2:15 AM, Andrea Brancatelli <[email protected]> 
> wrote:
> 
> Hi Adam, 
> 
> can you elaborate a bit on the "It's also possible to override resource
> settings on a per-replication basis" topic? 
> 
> I can't seem to find anything here:
> http://docs.couchdb.org/en/stable/replication/replicator.html 
> 
> Neither here:
> http://docs.couchdb.org/en/stable/api/server/common.html#replicate 
> 
> ---
> 
> Andrea Brancatelli
> 
> On 2018-10-30 17:17, Adam Kocoloski wrote:
> 
>> The `worker_processes` and `http_connections` in particular can have a 
>> significant impact on the resource consumption of each replication job. If 
>> your goal is to host a large number of lightweight replications you could 
>> reduce those settings, and then configure the scheduler to keep a large 
>> `max_jobs` running. It's also possible to override resource settings on a 
>> per-replication basis.

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