[Webhob] task types and outcomes

Barros Pena, Belen belen.barros.pena at intel.com
Thu May 30 03:57:56 PDT 2013

On 29/05/2013 22:39, "Richard Purdie" <richard.purdie at linuxfoundation.org>

>On Wed, 2013-05-29 at 16:57 +0100, Paul Eggleton wrote:
>> On Tuesday 28 May 2013 17:17:35 Barros Pena, Belen wrote:
>> > Thanks, Paul. I guess we need to nail down what is that we are trying
>> > achieve by reporting sstate tasks vs. built tasks vs. previously built
>> > tasks. From what I can remember, the main questions users need
>> > are:
>> > 
>> > * Why is this a built task when I was expecting it to reuse sstate
>> > * Why is this an sstate task when I was expecting it to build from
>> These are common questions yes.
>> > If those are indeed the main questions we need to answer, reporting
>> > sstate tasks and built tasks as one probably makes things easier. The
>> > metaphor would be a single task with a certain life cycle, and not 2
>> > separate tasks. So, "BitBake detected changes in the inputs for task
>>x and
>> > reran the task" would result in Web Hob reporting a single built task
>> > an sstate missed flag. If we report this case through 2 separate tasks
>> > we'll need to link them to each other, so that users can reach one
>> > the other and get a full picture of what BitBake did during the build.
>> > This is also a viable option, but it will result in a much longer
>>table of
>> > tasks, with 2 entries for a certain task + recipe combination.
>> > 
>> > Which way we report tasks impacts the way we structure the Web Hob
>> > table. From this classification of tasks:
>> > 
>> > * Sstate
>> > ** Missed
>> > ** Completed
>> > ** Failed
>> > 
>> > * Built
>> > ** Previously built
>> > ** Completed
>> > ** Failed
>> > 
>> > We would move to this one:
>> > 
>> > * Completed
>> > ** Previously built
>> > ** Sstate
>> > ** Built
>> > *** Sstate missed? Y/N
>> > *** Sstae failed? Y/N
>> > 
>> > * Failed
>> > ** Built
>> I think this is a reasonable approach. Although it does slightly
>>obscure the 
>> details of the tasks bitbake is running it's going to be a bit easier
>>for the 
>> user to follow with respect to the information they're most interested
>Sorry about the delayed reply, as you can tell I have a bit of a backlog
>today :(.
>I hate to complicate things however there is a touch of added complexity
>to consider.

>Imagine we have tasks A which depends upon B which depends
>upon C.
>In the no sstate available case, it builds C, then B then A, easy.
>With sstate, it will try A first. If A is available, it will just
>install A from sstate and skip B/C. If A is not available, it will try
>B, install that and skip C. It will then build any missing pieces so it
>might install B from sstate, then run C.

I see. So it seems we have also 'skipped' tasks.

>This means that giving the user meaningful numbers of tasks is hard for
>This can probably be presented in the above form fine, I just want to be
>clear about the subtleties involved. Ideally we do want to try and
>better convey to the user what happened too in this UI. It could be good
>if for example we could show that we didn't run C as B was from sstate
>and hence C wasn't needed.

I agree we should show those as well. So, it looks like we have a few
different kinds of tasks (previously built, skipped, sstate and built),
but those can be grouped into tasks that build something (the 'built'
kind, which we could call 'executed'), and those that don't build anything
(previously built, skipped and sstate, which we could call 'not

So for the 'all tasks' table, we could have a 'task type' column
classifying tasks as 'executed' and 'not executed'. Then, we could have an
'outcome' column that would classify tasks as 'succeeded', 'failed',
'previously built', 'sstate' and 'skipped'. That information is enough to
give me an overview of what BitBake has done, and if a task was handled in
an unexpected way (I thought it would build but it didn't, for example).

When I select a single task from that table, we could provide a 'task
history' section that would expose the BitBake process for that task (in
your example of sstate dependent tasks, for skipped task C the history
would tell me that task C was brought in by skipped task B, which in turn
was brought in by sstate task A. For sstate task A, the history would tell
me that the checksum did not change, that task A depended on skipped task
B, which path was searched to find the sstate object, and so on).

Would that work?

>I think the key concept we might also need to work into the UI is "dry
>run". A mode where you run the build however rather than doing it, it
>tells you what it would do (i.e. that it would need to run X tasks, Y
>would be done from sstate). Combined with an indication of why something
>didn't match, this would be extremely powerful/useful to most users.
>I have no objection to the form you present above, the key detail is
>more the dry run concept from the user perspective and start answering
>questions like "what would bitbake do?".

We should keep that 'dry run' mode in mind (even I can see it would be
incredibly useful), but it won't happen in 1.5 :(


Intel Corporation (UK) Limited
Registered No. 1134945 (England)
Registered Office: Pipers Way, Swindon SN3 1RJ
VAT No: 860 2173 47

This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.

More information about the toaster mailing list