On Fri, Feb 7, 2014 at 2:09 PM, Antonio Terceiro <terce...@debian.org>wrote:
> On Sun, Jan 26, 2014 at 06:09:51PM +0100, Martin Pitt wrote: > > I advise to use the schroot runner instead. schroots are easy to set > > up these days with mk-sbuild, and with some additional love (like > > installing and configuring apt-cacher-ng and symlinking > > /var/lib/schroot/union/overlay/ and /var/lib/schroot/unpack/ to /tmp/, > > and having /tmp on a tmpfs), set up, tear down, and package > > installation are extremely fast. > > This schroot tip is precious! I have just reduced the build time (which > was mostly spent installing dependencies -- I was already using > apt-cacher-ng) of a package from ~4min to ~30s! > > But instead of symlinking /var/lib/schroot/union/overlay/ยน , I configured > my sbuild chroots adding > > union-overlay-directory=/dev/shm > > > you can archive similar speeds without a tmpfs using eatmydata, just stick LD_PRELOAD=/usr/lib/libeatmydata/libeatmydata.so in your rc equivalent. This is also significantly faster than using dpkg --force-unsafe-io. Using mount options that reduce failure safety on the partition/subvolume holding the chroot build folder also helps a bit (nobarrier, data=writeback, commit=3600 etc.)