[poky] Sharing sstate

[Richard Purdie]

On Tue, 2011-09-27 at 08:22 -0600, Gary Thomas wrote:
> I'd really like to be able to share sstate effectively.  One problem I have with
> it is the size - for a build of my system (something similar to core-image-sato
> on BeagleBoard), the sstate cache for a build-from-scratch is nearly 5GB!  Not
> exactly simple to share across sites.
> 
> It seems to me that maybe I don't need to share everything.  For example, the
> webkit-gtk package:
> 
> $ ls -l sstate-cache/*webkit-gtk*
> -rw-rw-r-- 1 gary gary 331221793 Sep 23 16:21 
> sstate-cache/sstate-webkit-gtk-armv7a-vfp-neon-amltd-linux-gnueabi-1.5.1+svnr90727-r0-armv7a-vfp-neon-2-4a04fc210c0a565767a2ad9bb11d8322_deploy-ipk.tgz
> -rw-rw-r-- 1 gary gary     12740 Sep 23 16:21 
> sstate-cache/sstate-webkit-gtk-armv7a-vfp-neon-amltd-linux-gnueabi-1.5.1+svnr90727-r0-armv7a-vfp-neon-2-4a04fc210c0a565767a2ad9bb11d8322_deploy-ipk.tgz.siginfo
> -rw-r--r-- 1 gary gary 326376172 Sep 23 16:15 
> sstate-cache/sstate-webkit-gtk-armv7a-vfp-neon-amltd-linux-gnueabi-1.5.1+svnr90727-r0-armv7a-vfp-neon-2-67b4ac238844551dd48eed3255ea33d0_populate-sysroot.tgz
> -rw-r--r-- 1 gary gary     21652 Sep 23 16:15 
> sstate-cache/sstate-webkit-gtk-armv7a-vfp-neon-amltd-linux-gnueabi-1.5.1+svnr90727-r0-armv7a-vfp-neon-2-67b4ac238844551dd48eed3255ea33d0_populate-sysroot.tgz.siginfo
> -rw-r--r-- 1 gary gary 665832323 Sep 23 16:19 
> sstate-cache/sstate-webkit-gtk-armv7a-vfp-neon-amltd-linux-gnueabi-1.5.1+svnr90727-r0-armv7a-vfp-neon-2-726c31c08826bf24e6db77fdf5f4408b_package.tgz
> -rw-r--r-- 1 gary gary     98746 Sep 23 16:19 
> sstate-cache/sstate-webkit-gtk-armv7a-vfp-neon-amltd-linux-gnueabi-1.5.1+svnr90727-r0-armv7a-vfp-neon-2-726c31c08826bf24e6db77fdf5f4408b_package.tgz.siginfo
> -rw-rw-r-- 1 gary gary      3117 Sep 23 15:38 
> sstate-cache/sstate-webkit-gtk-armv7a-vfp-neon-amltd-linux-gnueabi-1.5.1+svnr90727-r0-armv7a-vfp-neon-2-f9267d59a61b218bd6ab76ed55f12e8e_populate-lic.tgz
> -rw-rw-r-- 1 gary gary      8359 Sep 23 15:38 
> sstate-cache/sstate-webkit-gtk-armv7a-vfp-neon-amltd-linux-gnueabi-1.5.1+svnr90727-r0-armv7a-vfp-neon-2-f9267d59a61b218bd6ab76ed55f12e8e_populate-lic.tgz.siginfo
> 
> Would it be possible to only share part of this, maybe the "package" file?
> It seems to me that this could make the needed (shared) cache much smaller...

The build will only use the pieces it needs. If your build only needs
the deploy-ipk pieces and doesn't need to write new packages files it
can survive without the package part. If it doesn't need to compile
something against webkit, it won't use the populate-sysroot file.

So what I'm saying is you likely could get away with not sharing the
*_package files at least. The only downside is if you turn on rpm
packaging it would have to rebuild.

Cheers,

Richard