out of memory - Stopping Couchbase Elasticsearch XDCR OutOfMemory Error -

I am running a proof of concept on VM with 4 GB Ram. I have around 2 million docs in Couchbase and they all want to use the XCDR plugin in LCLSec, although Couchbase ES is very difficult and falls on ES. I have not had enough room to increase the memory before the 1 GB default, is there a way to slow down the S room to give breath?

Edit:

I should add some history here. I used to do this work, EE Couchbase was indexing documents very quickly, but then I ran away from disk space on my VM. I've added a new disc and changed the path.data property in elasticsearch.yml. After this I could not start ES using the given init.d script in IBS. It says that the e-start is OK, but then if I run the /etc/init.d/elasticsearch status then it says "elastic service server is not running but pid file exists". I just installed it again just for hell but nothing was done. How can I know about the failure to run the Init script? I can start ES completely again manually and if the Couchbase is all running then everything is cool. I'm not sure that it Is relevant, but at some point I need to do the same.

Do you have a small number in elasticsearch.yml couchbase.maxConcurrentRequests: 1024 Can you try to modify? Maybe it can set up to 256?