[U-Boot] [U-Boot, 1/2] common: Add CCACHE variable to allow use of ccache

[York Sun]

On 08/22/2013 12:36 PM, Marek Vasut wrote:
> 
> There is an env variable to configure separate ccache cache dir , so just by 
> setting that. But then , when each build ends, you would need to clean it up 
> somehow. It was mentioned in the discussion with the patch. You can try working 
> on this some more and post a patch, then we can talk about further forging of 
> this.
> 

I fixed the 2nd patch and I am running MAKEALL with individual board
folder for ccache. The compiling time for the first run on my laptop is
56 minutes. The 2nd run is 23 minutes. About the same improvement if
using a big unified cache for all boards. By the way, each board cache
is about 7~8MB.

You set my expectation high. I was hoping to get 10x or more improvement.

York