[oe] Multiple bitbake and a shared DL_DIR location - race conditions?

[Leon Woestenberg]

Hello Koen,

>  | I would like to allow the builds to overlap in time, at least make
>  | sure the builds are robust to this, but I doubt this is possible at
>  | all.
>  |
>  | Are there any race conditions with the current approach?
>  |
>  | I.e. what if two fetch tasks from concurrent instances of bitbake
>  | decide to download a package?
>
>  Isn't that what the .lock files are supposed to do? If you have multiple
>  bitbake threads (in one bitbake instance) it has to solve the same problem.
>
Maybe, I did not fully understand how the go() function in
"lib/bb/fetch/__init__.py" could handle this case:

Suppose at time T one bitbake instance #1 is downloading/fetching
package A, and bitbake instance #2 at time T would like to fetch the
same package, what will #2 do?

Will it wait for the lock to be released, then check?

Regards,
-- 
Leon