I've been using Logstash and Elasticsearch for a while now and have survived using a 1g object heap for development. However, I can not get the heap to go over 1150Mb before it says I can not reserve enough space for the heap, and my configurations are becoming more demanding. I first noticed this when trying to use a double logstash input (S3 and file).
All the size tweaking I have been doing has been in logstash jvm.options and elasticsearch setup.bat. I have a user environmental variable set:
_JAVA_OPTIONS => -Xmx2g -Xms2g
I am running everything on JDK and JRE 1.8.0_141. PC has 32g of RAM on Windows 7.