doc: add details about rss on process.memoryUsage

1. `process.memoryUsage()` returns an object with 4 keys: `rss, heapTotal, headUsed, external`. There were brief explanations for the rest except `rss`. This commit adds this on the docs. 2. A little more clarity on `rss` to help people disambiguate it from the virtual memory size. PR-URL: nodejs#16566 Refs: nodejs#16566 (comment) Reviewed-By: Refael Ackermann <[email protected]> Reviewed-By: Gibson Fahnestock <[email protected]> Reviewed-By: Gireesh Punathil <[email protected]> Reviewed-By: James M Snell <[email protected]> Reviewed-By: Luigi Pinca <[email protected]>
cjihrig · Nov 6, 2017 · 09181eb · 09181eb
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commit 09181eb
Showing 1 changed file with 7 additions and 1 deletion.
diff --git a/doc/api/process.md b/doc/api/process.md
@@ -1282,7 +1282,13 @@ Will generate:
 
 `heapTotal` and `heapUsed` refer to V8's memory usage.
 `external` refers to the memory usage of C++ objects bound to JavaScript
-objects managed by V8.
+objects managed by V8. `rss`, Resident Set Size, is the amount of space
+occupied in the main memory device (that is a subset of the total allocated
+memory) for the process, which includes the _heap_, _code segment_ and _stack_.
+
+The _heap_ is where objects, strings and closures are stored. Variables are
+stored in the _stack_ and the actual JavaScript code resides in the
+_code segment_.
 
 ## process.nextTick(callback[, ...args])
 <!-- YAML