Sluggish GD plotting

Sluggish GD plotting

am 26.09.2007 12:34:34 von Erik Kullberg

I have a technical simulation program, written in PHP. The result of the
simulation is presented in shape of time history diagrams on the screen.

The program first calculates everything and stores the result in a double
indexed array, one row per time frame, one column per variable. This array
is then input to a plot function, which creates the diagrams by use of GD2.

In my local environment a certain run with this program takes about 5 sec.
On the internet server (a web hotel) the same run sometimes takes 3 min. or
more! Sometimes the result diagrams are not delivered at all.

I can conclude that the calculations are always completed, also in cases
when there is no output diagams, so one might suspect that the trouble is
connected to the plotting.

Is GD working in a memory compartment of its own, the size of which is too
little on that server?

Suggestions?

/ Erik

Re: Sluggish GD plotting

am 26.09.2007 16:52:36 von Erik Kullberg

I have made a more thorough check of run times and found that
GD is innocent!
12 runs gave an average total run time of 156 sec, min value 6 sec, max
value 368 sec.
The part time for GD was <1 sec in all cases!

The same run takes a total of 3 sec locally.

/ Erik


"Erik Kullberg" skrev i meddelandet
news:_AqKi.9730$ZA.5583@newsb.telia.net...
>I have a technical simulation program, written in PHP. The result of the
>simulation is presented in shape of time history diagrams on the screen.
>
> The program first calculates everything and stores the result in a double
> indexed array, one row per time frame, one column per variable. This array
> is then input to a plot function, which creates the diagrams by use of
> GD2.
>
> In my local environment a certain run with this program takes about 5 sec.
> On the internet server (a web hotel) the same run sometimes takes 3 min.
> or more! Sometimes the result diagrams are not delivered at all.
>
> I can conclude that the calculations are always completed, also in cases
> when there is no output diagams, so one might suspect that the trouble is
> connected to the plotting.
>
> Is GD working in a memory compartment of its own, the size of which is too
> little on that server?
>
> Suggestions?
>
> / Erik
>
>