Re: Updated disc cache

On Fri, Apr 03, 2015 at 02:39:05PM +0100, cj wrote:
> In article <mpro.nm8dx001qojsl00l7.pittdj@pittdj.co.uk>,
> David Pitt <pittdj@pittdj.co.uk> wrote:
> > Hmm! My Iyonix did over three time better than that, and there was
> > no "too slow" message. My test piece was http://www.dailymail.co.uk
> > because that is a particularly heavy duty site.
>
> OK. A lot of random browsing around that site led to:
>
> (5743.130000) content/llcache.c llcache_finalise 3352: Backing store
> average bandwidth 531777 bytes/second
>
> which is over 5 times faster. However, I thought we would be talking
> drive speed, which shouldn't be affected by the download speed of any
> particular site, or am I completely up the wrong alley?

That value is *purely* the total amount *written* to disc divided by
how long the write operations took. The write time includes all
directory creation/seek operations etc. rather than just the raw disc
write performance.

Anything above a megabit a second (125000 bytes/second) will not
trigger the warning about low write speed. I set it there because
below that value the overheads of disc caching exceed the benefit of
simply fetching data from the network.

>
> --
> Chris Johnson
>
>

--
Regards Vincent
http://www.kyllikki.org/