On Tue, Jun 26, 2001 at 06:21:21PM -0300, Rik van Riel wrote:
> > * If we're getting low cache hit rates, don't flush
> > processes to swap.
> > * If we're getting good cache hit rates, flush old, idle
> > processes to swap.
>
> ... but I fail to see this one. If we get a low cache hit
> rate, couldn't that just mean we allocated too little memory
> for the cache ?
Hmmm. I didn't take that into consideration. But at the
same time, shouldn't a VM be able to determine that its cache
strategy is causing _more_ (absolute) misses by increasing it
cache size? The percentage of misses may go down, but total
device I/O may stay the same.
So let's see... I'll rephrase that 'Motiviation' as:
* Minimize the total medium/slow I/Os that occur over a
sliding window of time.
Is that a more general case?
> Also, how would we translate all these requirements into
> VM strategies ?
First, I would like to translate them into measurements.
Once we know how to measure these criteria, its possible to
formalize the feedback mechanism/accounting that a VM should
be aware of.
In the end, I would like a VM to have some idea of
how well its performing, and be able to attempt various
well-known strategies based upon its own performance.
--
Jason McMullan, Senior Linux Consultant
Linuxcare, Inc. 412.432.6457 tel, 412.656.3519 cell
[EMAIL PROTECTED], http://www.linuxcare.com/
Linuxcare. Putting open source to work.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/