Re: [abc-users] Relational aspects running time

You run out of memory at i=8? That makes no sense to me. I have no idea...

If I find the time I will look into it next week.

Strangely, we did similar benchmarks for our paper (available on our
website) and found no such odd behavior.

Eric

On 16/03/2008, Alan Teoh <alan.teoh07_at_imperial.ac.uk> wrote:
> Hi Eric,
> Perhaps my previous benchmark was a bit too small to be an indicator of
> anything.
>
> The following was the full code that I used. The relational aspect and
> the Bit remain the same.
>
>
> class Test {
> public static void main(String[] args) {
> Bit[] bits = new Bit[10000];
> Bit b1 = new Bit();
> Bit b2 = new Bit();
>
> for(int i = 0; i < 10000; i++) {
> bits[i] = new Bit();
> }
> // Test memory consumption
> for(int i = 0; i < 5000; i+=2) {
> Equality.associate(bits[i], bits[i+1]); // Problem seems to
> start here
> System.out.println(i);
> }
>
> Equality.associate(b1, b2);
> // Test running time
> long time;
> for(int i = 0; i < 10; i++) {
> time = System.currentTimeMillis();
>
> for(int j = 0; j < 1000000; j++) {
> b1.set();
> b1.clear();
> }
>
> System.out.println("Operation took " +
> (System.currentTimeMillis() - time) + " milliseconds");
> }
> }
> }
>
> I ran the same code with association aspects (using the aspect provided
> by the paper by Sakurai et al.), and the benchmark was over in a few
> seconds. However, with relational aspects, the computation seems to take
> some time in the loop (for(int i = 0; i < 5000; i+=2) ). In fact,
> memory(Java heap space) runs out when i = 8. And as in the previous
> email, when I commented the relational advices off, the code will run
> and finish quickly without such problems. Obviously, by doing
> that(commenting the relational advices) I would have defeated the point
> of relational aspects, so that was the reason why I was wondering what
> could be wrong with it?
>
> Thanks again.
>
>
> Eric Bodden wrote:
> > Hi, Alan.
> >
> > Your benchmark is way too small to conclude anything at all about running time.
> >
> > In general, as we write in the paper, relational aspects *are* slower
> > than the implementation by Sakurai et al.. However, there should be no
> > exponential increase.
> >
> > Eric
> >
> >
> >
> > On 16/03/2008, Alan Teoh <alan.teoh07_at_imperial.ac.uk> wrote:
> >
> >> Hello,
> >>
> >> I have been playing around with relational aspects, and I stumbled upon
> >> a problem with its running time. Code is as follows (using Sakurai et
> >> al's Bit idea from association aspects, as well as the relational aspect
> >> from the relational aspects paper):
> >>
> >> class Bit {
> >> boolean value = false;
> >> public void set() { value = true; }
> >> public void clear() { value = false; }
> >> boolean get() { return value; }
> >> }
> >>
> >> Relational aspect is as follows:
> >>
> >> relational aspect Equality(Bit b1, Bit b2) {
> >> relational after(): call(public void Bit.set()) && target(b1) {
> >> b2.set();
> >> }
> >> relational after(): call(public void Bit.clear()) && target(b1) {
> >> b2.clear();
> >> }
> >> }
> >>
> >> Using this Test file:
> >> class Test {
> >> public static void main(String[] args) {
> >> Bit[] Bits = new Bit[10000];
> >> Bit b1 = new Bit();
> >> Bit b2 = new Bit();
> >> Bit b3 = new Bit();
> >> Bit b4 = new Bit();
> >> Bit b5 = new Bit();
> >> Bit b6 = new Bit();
> >> Bit b7 = new Bit();
> >> Bit b8 = new Bit();
> >> Bit b9 = new Bit();
> >> Bit b10 = new Bit();
> >> Equality.associate(b1, b2);
> >> Equality.associate(b3, b4);
> >> Equality.associate(b5, b6);
> >> Equality.associate(b7, b8);
> >> Equality.associate(b9, b10);
> >> }
> >> }
> >>
> >> My problem is that whenever I try to associate more and more Bit
> >> objects, the running time just increases in an exponential manner. When
> >> I comment the relational advices out however, the running time is quick,
> >> thus the relational advices are causing the problem here. I realise that
> >> for every relational advice is made up by a tracematch. However, I do
> >> not see how it actually affects the running time in such a drastic
> >> manner, given that the only amount of objects(which are visible to me)
> >> that are involved here are only 10, and there are only 5 aspect
> >> instances. Explanation on this matter would be greatly appreciated.
> >>
> >> Many thanks.
> >>
> >>
> >>
> >>
> >>
> >>
> >
> >
> >
>
>
>

-- 
Eric Bodden
Sable Research Group
McGill University, Montréal, Canada