[packagekit] viability of the current yum backend ?

[Richard Hughes]

On Wed, 2008-01-02 at 17:16 -0500, David Zeuthen wrote:
> Keep in mind that whenever you add caching you need to care about
> coherency and whatnot. The devil in the detail here, broadly speaking,
> is that cache coherency issues pops up when you least expect. And
> normally it's very hard to debug such things.

Totally. With the updates cache we drop it as soon as yum does anything
behind our back, or for that matter, when we do anything crazy like
manually updating the cache.

> So unless it's worth it, try avoid caching as much as you can. Or,
> rather, implement the cache as low in the stack as possible (e.g. in the
> yum/rpm code base itself). This is because of the fact that the IPC
> overhead from pk-update-icon<->message bus<->packagekitd<->yum-backend
> is close to negligible compared to human response times (> 20ms)

Point taken and processed. Robin was thinking about something clever
with a python process but we'll have to bribe him with beer to get more
information. :-)

Richard.