Document parallel execution (-j flag)

README.md

@@ -205,6 +205,24 @@ You can enable verbose mode by calling Make with the variable
 $ V=1 make
 ```
 
+Parallel execution can be enabled through the use of the
+`-j` option. The following output showcases concurrent
+downloading of dependencies.
+
+``` bash
+$ make -j32
+Cloning into '/home/essen/ninenines/cowboy/deps/ranch'...
+Cloning into '/home/essen/ninenines/cowboy/deps/cowlib'...
+```
+
+The``MAKEFLAGS` variable can be used to set it permanently
+on your system. It can be set in your `.zshrc`, `.bashrc`
+or equivalent file.
+
+``` bash
+MAKEFLAGS=-j32
+```
+
 Core package functionality
 --------------------------
 

core/core.mk

@@ -42,7 +42,7 @@ help::
 		"erlang.mk (version $(ERLANG_MK_VERSION)) is distributed under the terms of the ISC License." \
 		"Copyright (c) 2013-2014 Loïc Hoguin <essen@ninenines.eu>" \
 		"" \
-		"Usage: [V=1] make [target]" \
+		"Usage: [V=1] make [-jNUM] [target]" \
 		"" \
 		"Core targets:" \
 		"  all         Run deps, app and rel targets in that order" \
@@ -58,7 +58,8 @@ help::
 		"The target clean only removes files that are commonly removed." \
 		"Dependencies and releases are left untouched." \
 		"" \
-		"Setting V=1 when calling make enables verbose mode."
+		"Setting V=1 when calling make enables verbose mode." \
+		"Parallel execution is supported through the -j Make flag."
 
 # Core functions.
 

erlang.mk

@@ -42,7 +42,7 @@ help::
 		"erlang.mk (version $(ERLANG_MK_VERSION)) is distributed under the terms of the ISC License." \
 		"Copyright (c) 2013-2014 Loïc Hoguin <essen@ninenines.eu>" \
 		"" \
-		"Usage: [V=1] make [target]" \
+		"Usage: [V=1] make [-jNUM] [target]" \
 		"" \
 		"Core targets:" \
 		"  all         Run deps, app and rel targets in that order" \
@@ -58,7 +58,8 @@ help::
 		"The target clean only removes files that are commonly removed." \
 		"Dependencies and releases are left untouched." \
 		"" \
-		"Setting V=1 when calling make enables verbose mode."
+		"Setting V=1 when calling make enables verbose mode." \
+		"Parallel execution is supported through the -j Make flag."
 
 # Core functions.