[poky] sstate status

[Tian, Kevin]

>From: Gary Thomas
>Sent: Saturday, December 04, 2010 8:48 PM
>
>On 12/03/2010 04:31 PM, Gary Thomas wrote:
>> On 12/03/2010 09:34 AM, Paul Eggleton wrote:
>>> Hi all,
>>>
>>> I've been doing some tests with sstate, and I've managed to get to a
>>> stage where I can share the SSTATE_DIR between my two machines (one
>>> running Fedora 14 and the other Kubuntu 10.10) and almost get a
>>> successful build from a clean TMPDIR. My last test got to
>>> poky-image-minimal.do_rootfs and then failed due to some kind of
>>> package dependency issue:
>>>
>>> --------- snip ---------
>>> | Processing rpm...
>>> | Processing zypper...
>>> | error: Failed dependencies:
>>> | elfutils>= 0.148 is needed by rpm-5.1.10-r7.i586
>>> | libaugeas0>= 0.7.3 is needed by
>>> zypper-1.4.7+git0+9eb0e248e06c8d20ad054be2439149d9ede37531-r1.i586
>>> | ERROR: Task failed: ('function do_rootfs failed',
>>>
>'/home/pokystuff/tmp/work/qemux86-poky-linux/poky-image-minimal-1.0-r0/temp/log.
>do_rootfs.6874')
>>>
>>> --------- snip ---------
>>>
>>> A "bitbake -c clean augeas elfutils" and then "bitbake
>>> poky-image-minimal" again went through OK (and built the
>>> aforementioned recipes from sstate) , so I'm not sure what went wrong
>>> here.
>>>
>>> My current state of work is in the paule/sstate contrib branch, which
>>> is based on Kevin's tk/sstate branch. Kevin, I think the sooner we can
>>> move this towards master the better, then we can get some wider testing.
>>>
>>> FYI Joshua has made bug #507 into a tracking bug for current sstate
>>> issues:
>>> http://bugzilla.pokylinux.org/show_bug.cgi?id=507
>>
>> I gave this a simple try and it failed miserably. Working from a copy of
>> Paul's branch in poky-contrib, here's what I did:
>>
>> * On machine A (x86 Fedora 11)
>> % bitbake poky-image-minimal
>>
>> * On machine B (x86 Fedora 13)
>> -- Copy sstate-cache from machine A to /tmp/sstate-cache (rsync with
>> all perms & timestamps preserved)
>> -- Using the identical conf/local.conf file from machine A, except
>> I set up SSTATE_MIRRORS like this
>> SSTATE_MIRRORS ?= "\
>> file://.* file:///tmp/sstate-cache/"
>> % bitbake poky-image-minimal
>>
>> Fell apart pretty badly. Look at the output
>> http://www.mlbassoc.com/poky/poky_with_sstate.out
>>
>> Also, it seemed to be rebuilding a lot of packages. IMO, there's
>> no reason it should have to rebuild _any_
>>
>
>One thing that seems to be significant is the base build directory path.
>In the case above, they did not match, i.e.
>   * On machine A, BUILDDIR=/tmp/sstate_testing
>   * On machine B, BUILDDIR=/home/local/my_sstate_test
>I tried it this way as it matches my [customer's] expected usage.

I think in usual case the directory paths would mismatch. So let's stick to that
configuration to expose more issues. In my previous debug, I have made it
in a good shape but would now turn to RP's branch to try more experiments.

It would be good if you also try that one:
http://git.pokylinux.org/cgit/cgit.cgi/poky-contrib/log/?h=rpurdie/tweaks2

>
>I've rerun the experiment again where I used identical paths on both
>machines and the results were vastly improved.  It still takes a horrible
>length of time (64 minutes on a fast 4 processor box) and rebuilds way to
>many packages for just replaying what's already been done though (IMO).
>Results are at
>   http://www.mlbassoc.com/poky/poky_with_sstate_same_paths.out
>

In my run ~25min are consumed just for sstate check/installation on a NHM 4-core box. 
then several minutes for rootfs generation if two builds totally match. the slow sstate
phase comes from same reason as a slow build - the 'exec' overhead. I use 'sato' as
the target.

In your case, however there're still some packages rebuilt, such as gzip-native,
unifdef-native, eglibc-initial, ncurses, etc. and also gcc related packages are rebuilt 
which just consumes time. Has your source tree changed between the two builds?

Thanks
Kevin