[bitbake-devel] New progress meters

[Paul Eggleton]

Hi Gary,

On Tue, 19 Jul 2016 08:33:54 Gary Thomas wrote:
> I quite like the new progress meters, but they seem to not be very
> accurate.  I was just rebuilding webkitgtk and got this:
> 
> 0: webkitgtk-2.12.3-r0 do_compile (pid 30494)  96%
> |#######################################  | ETA:  0:02:58
> 
> Sadly, it sat there, waffling between 02:58 and 03:44 for about
> 10 minutes...
> 
> * How is this [estimate] calculated?
> * Should I be concerned when it's not accurate (or even moving)?

There are a few different types of progress handling for different types of 
tasks. To be specific in this example, for recipes that inherit cmake during 
do_compile we report the progress that the cmake-produced makefile prints out. 
The ETA, which is implemented in the python-progressbar code we are using is 
kind of a rolling average calculated based on recent progress, so it's 
possible it's inaccurate in this instance if there are places where it stalls. 
Python-progressbar has an alternative ETA mode which we could try, but to be 
honest when the progress value sent to it isn't evenly apportioned with 
respect to time and we don't have any weighting information, there's not a lot 
anyone can do to estimate time remaining accurately. If it's truly bothersome 
we could just turn off the ETA display I suppose.

> n.b. I wasn't sure the best place for this question, the bitbake
> list, generic Yocto or OE-core.  Feel free to redirect as needed.

Technically this is an OE question although I know that isn't obvious - there 
are parts of this that are implemented in BitBake and parts in OE, so asking 
here is fine.

Cheers,
Paul

-- 

Paul Eggleton
Intel Open Source Technology Centre