How does YARN decide if remaining memory is enough AM allocation Hi all,
Somewhat of a newb here so hopefully this question isn't too trivial. I want to know how YARN decides if the remaining memory after AM resource allocation is "enough". Here's a breakdown of what's going on in my particular case. We have a YARN queue that has ~1.7GB memory allocated to it. We have a parent MR job that spawns multiple child jobs. The AM container memory for the parent job is configured to 1GB. Once the AM container gets allocated its 1GB there is a remaining ~0.7GB memory available. In my case that 0.7GB is enough for the child jobs to succeed. My question is, what if that remaining amount wasn't 0.7GB but something much less, like 0.1GB, or 0.0001GB? How does YARN handle those cases - will it allocate *any* remaining resources to the child jobs? Will there be a ton of thrashing if there is only a small amount of memory available? Thanks for any help, or a pointer in the right direction!
