on coaster accounting (was Re: [Swift-devel] current workers < 0 ?)

[Mihael Hategan]

----- Allan Espinosa <aespinosa at cs.uchicago.edu> wrote:
> So the Requested list is for the tasks being received and not the
> "make coaster" request to the LRM?

The requested list is to track all the workers that the manager plans
to have started and has put a request for to the underlying provider
(LRM, but see below) but haven't yet started or failed.

The manager attempting to start a job is not the same as that job being
in the LRM queue. Between delays, asynchronicity, and just weird job 
managers/LRMs, stuff happens.

> 
> also, currentWorkers is the "demand" for coasters and not the number
> of coasters that are available (busy or ready)

Right. It's supposed to track the total amount of workers: busy, ready,
and starting.

> 
> thus the best way to graph a "number of avail processors" & "current
> usage" vs time is using the size of Ids and Busy right?

Somewhat. Busy will tell you the workers the manager thinks are 
running jobs.

Ids is there to allow quick lookup of a worker based on its id. I'm not
sure what stages of a worker's life (busy, ready, starting) it includes.

> 
> On Thu, Feb 26, 2009 at 1:03 PM, Mihael Hategan <hategan at mcs.anl.gov> wrote:
> > There are 50 running workers and 61 somewhere between being submitted
> > and contacting the service. What's the question?
> >