CCache is a compiler cache for C/C++. It speeds up recompilation by caching the result of previous compilations and detecting when the same compilation is being done again. We can use this tool to speed up cocos2d-x android compilation.

    The following  instructions are tested on Mac:

Installation:

You can use homebrew:

    brew install --HEAD ccache

Or install by source:

    git clone https://github.com/jrosdahl/ccache.git

    cd ccache

    ./autogen.sh

   ./configure

    make

    make install

If bash prompts it can not find autoheader, you need install automake:

    brew install automake

But, if bash complains it can not find brew, you need install one:

    ruby -e "$(curl -fsSL https://raw.github.com/Homebrew/homebrew/go/install)"

make sure ccache can be found in your $PATH, run command:

    ccache

If you can not see the help message, check your installation.

Configuration

To use CCache, you need setup some environment variables:

   vim ~/.bash_profile  

Add following lines:

  export USE_CCACHE=1

  export NDK_CCACHE=/usr/local/bin/ccache

Then run command:

  ccache -M 10G

This command will set max cache size to 10G, If your mac have a large hard disk, you can set the cache size to 50G.

Then, find your NDK path, if you forget where you put it, try the following command:

  which ndk-build

This is the result on my mbp:

/developer/android/android-ndk-r9b/ndk-build

So my NDK_ROOT is:

/developer/android/android-ndk-r9b

Open file: $NDK_ROOT/build/core/default-build-commands.mk

find the following section，Add ccache as shown:

# IMPORTANT: The following definitions must use lazy assignment because
# the value of TOOLCHAIN_PREFIX or TARGET_CFLAGS can be changed later by
# the toolchain‘s setup.mk script.
#
ifneq ($(findstring ccc-analyzer,$(CC)),)
TARGET_CC       = $(CC)
else
TARGET_CC       = ccache $(TOOLCHAIN_PREFIX)gcc    #Add ccache support
endif
TARGET_CFLAGS   =
TARGET_CONLYFLAGS =
ifneq ($(findstring c++-analyzer,$(CXX)),)
TARGET_CXX      = $(CXX)
else

TARGET_CXX      = ccache $(TOOLCHAIN_PREFIX)g++ #Add ccache support

endif
TARGET_CXXFLAGS = $(TARGET_CFLAGS) -fno-exceptions -fno-rtti

Build

Switch to cocos2d-x root path, run:

   python build/android-build.py -p 10 cpp-tests 

Open another bash window, run:

 ccache -s

this command will print the ccache statistics,

cache directory                     /Users/heliclei/.ccache
primary config                      /Users/heliclei/.ccache/ccache.conf
secondary config      (readonly)    /usr/local/etc/ccache.conf
cache hit (direct)                 13588
cache hit (preprocessed)           11145
cache miss                          4696
called for link                        1
called for preprocessing              14
preprocessor error                     1
can‘t use precompiled header        1629
no input file                          5
files in cache                     32222
cache size                           5.4 GB
max cache size                      30.0 GB

If both cache hit & cache size are 0, that means ccache doesn‘t work, you need check your configuration.