openstack team mailing list archive

[Julien Danjou <julien@xxxxxxxxxxx>]

On Wed, Oct 31 2012, Doug Hellmann wrote:

> Is that better than just reporting the data in a more easily digested
> format in the first place?

IMHO yes.

> Julien, I don't understand your comment about losing data "if your system
> is not launched to compute delta". Can you clarify what you mean there? I
> do understand that the agent would need to store state about the counter
> locally in order to track the delta value, but I think we could provide a
> convenient way for pollsters to do that without complicating them
> excessively.

Yes, actually I think you got what I meant, I just wrote it badly. By
system, I meant pollster. If your pollster is not running to compute
delta and you have no state stored, you'll miss a part of what has been
used.

Now, I don't think trying to circumvente that at the pollster level is a
good idea either, because it complicates the pollster for no good reason.

Ultimately, if you reaaalllly want to compute delta instead of using the
real values of the counter for whatever (bad) reaason, doing it at the
storage back-end lavel might be an option if you want. But as I said,
for now there's now reason it should be needed.

(And you know what they say, early optimization is the root of all evil :)

-- 
Julien Danjou
// Free Software hacker & freelance
// http://julien.danjou.info

Attachment: pgpDG9jV8EhKf.pgp
Description: PGP signature