Speed difference under load

[K J]

>
>  Depending on the language and runtime, you could almost count on it while
> libraries load and initialize and jits optimize.
>
>
> Testers usually include some ramp-up time where things sort of warm-up
> before you actually start capturing metrics.
>

So it's normal to have Memcache's response time be 1 second, if the
system is relatively idle?  This happens when I'm basically the only user on
the system, logging in, checking pages, etc.





On 10/27/07, Dustin Sallings <dustin at spy.net> wrote:
>
>
>
>   Depending on the language and runtime, you could almost count on it
> while libraries load and initialize and jits optimize.
>
>
>   Testers usually include some ramp-up time where things sort of warm-up
> before you actually start capturing metrics.
>
> --  Dustin Sallings (mobile)
>
> On Oct 26, 2007, at 20:24, "K J" <sanbat at gmail.com> wrote:
>
>
>
>  Ok I tested this, and found that the very first memcache get request
> always takes up 1 second.  All subsequent gets in the same page are fast.
> Does anyone know what could cause the first memcache get request to slow
> down like this?
>
>
>
>
>
>
>
>
> On 10/25/07, John Kramlich <john.kramlich at gigoit.org> wrote:
> >
> > J A wrote:
> > > In my application I've noticed something weird.  When testing it with
> > > one user, the memcached page loads in like 1 second, but when I use a
> > > load testing software and put 20 simultaneous users on it, the page
> > > load goes to 0.01 second, even though the server load has gone up.
> > >
> > > I'm puzzled by this.  Anyone have similar experiences?
> > >
> >
> > What load testing software are you using and what happens if you
> > configure that load testing software to emulate only a single user?  If
> > you are running something like siege locally on your server then network
> >
> > latency would be much lower than if you were running the same program on
> > a remote machine.  That may be what makes the page load more slowly.
> >
> > You may also want to profile you code and see how long returning results
> >
> > from memcache takes.  If using PHP you can get a benchmarking class from
> > PEAR and set start and stop markers before and after you memcache
> > related code.  Then you can output the number of milliseconds it takes
> > to execute that code.  You can do this for other parts of your code as
> > well.  It certainly helps when figuring out where to spend time
> > optimizing.
> >
> > - John Kramlich
> > ------------------------------
> > http://www.gigoit.org  - Give and get free items within your community
> >
>
>
>
>
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