[OE-core] [PATCH] bitbake.conf: point PERSISTENT_DIR outside TMPDIR

[Richard Purdie]

On Fri, 2011-03-04 at 15:26 +0100, Koen Kooi wrote:
> Op 4 mrt 2011, om 15:01 heeft Richard Purdie het volgende geschreven:
> 
> > On Fri, 2011-03-04 at 11:40 +0100, Martin Jansa wrote:
> >> * sanity check warning user that he still has peristent cache in old location
> >> * similar patch was sent to OE, to keep PERSISTENT_DIR location consistent
> >>  http://lists.linuxtogo.org/pipermail/openembedded-devel/2011-March/030623.html
> >> 
> >> Signed-off-by: Martin Jansa <Martin.Jansa at gmail.com>
> >> ---
> >> meta/classes/sanity.bbclass |    8 ++++++++
> >> meta/conf/bitbake.conf      |    2 +-
> >> meta/conf/sanity.conf       |    1 +
> >> 3 files changed, 10 insertions(+), 1 deletions(-)
> > 
> > When I saw this on the OE list, I'd assumed you'd done what Poky had
> > done, I've just realised you're moving this file to TOPDIR instead of
> > TMPDIR.
> > 
> > My big concern here is that we really shouldn't be writing to data to
> > the conf directory as its not what the user expects.
> > 
> > I say this knowing the raft of usability problems we've had every time
> > we take something outside of TMPDIR as users have the expectation that
> > deleting tmp wipes out all stored state and rebuilds. Having this file
> > hidden in the conf directory breaks that expectation. Note there are
> > only two things we place outside of TMPDIR, downloads and sstate data.
> 
> And pseudodone! That one nearly always trips me up :)

We should at least be a lot better about working out when that file is
valid these days. 

The reason for that file and its location is its near impossible to work
out where TMPDIR is in the general case without calling bitbake. Like
most good cache files, in that case we can now tell when its invalid and
rebuild it if it is missing for any reason with no really nasty
implications.

Cheers,

Richard