[Tilesathome] [server]

[Sebastian Spaeth]

On Sun, 28 Mar 2010 11:31:02 +0200, Florian Lohoff <f at zz.de> wrote:
> As i already mentioned i think a year ago - When looking at the load
> of my renderers it seems very "spiky" - so when we have the hourly?
> render prio 2 stuff coming in the clients start rendering - as soon
> as the prio 2 are done we come back to the prio4 and lots of clients
> stall because of the incoming queue.
> 
> Here is a munin of a 8 Core 16GB Renderer sitting idle >50% of the
> time:
> 
> https://hydra.gt.owl.de/munin/lab.rfc822.org/bs4.lab.rfc822.org-cpu.html

Any help to make the render dispatching smarter is accepted :-).

> I would see 2 solutions/optimizations - let the prio2 rerender
> stuff run much more often - like depend on the minutely replication
> diffs. So we sprinkel prio2 into the queue much more often so that
> halve of the clients render prio2 and half of them render the oldtile
> stuff all the time.

I would be all in favor for that if we were not running at full server
capacity anyway. But running the prio2 rerender every few minute gives
us more total work to do, as we need to rerender all intermediary
changes of edits rather than only looking at them once every while.

> Another would be to make it not a prio1 then prio2 then
> prio3 4 ... but rather a kind of "weighted fair queue". So once we have
> a bunch of prio1/2 in the queue we not start swamping the clients with them
> but rather try to feed some clients prio4 which come back fast (typically)
> and let the incoming not drain.

Yep, that does sound more feasible to me.

Sebastian