Hi Anto,

Here are my numbers:

skyvase.pov rendered in 1024x768 in 1 Tiles (-) from 08-23-2003 / 11:53:28
to 08-23-2003 / 11:54:15 (47).

skyvase.pov rendered in 1024x768 in 2 Tiles (H) from 08-23-2003 / 11:54:22
to 08-23-2003 / 11:54:58 (36).

skyvase.pov rendered in 1024x768 in 2 Tiles (V) from 08-23-2003 / 11:55:04
to 08-23-2003 / 11:55:52 (48).

skyvase.pov rendered in 1024x768 in 4 Tiles (H) from 08-23-2003 / 11:56:10
to 08-23-2003 / 11:57:02 (52).

However - all rendered locally with my 2 CPU's. You see the Overhead when I
make 4 tiles makes it even slower then when I render this in 1 tile.

In one sentece: Scenes which need only very short rendering (30 Seconds) may
not be the best candidates for SMPOV and Hyperthreading. I have counted that
even before the second instance starts up, 4 Seconds are gone.

Your numbers:
38 Second - 29 Seconds = 9 Seconds diffrence. How long does it take for your
POV-Ray to load?

Remeber we load two instances of POV-Ray. Secondly they start up and load
the POV-File.

Did you include the "loading time" while measuring the 29 Seconds?
Maybe in that case POV-Ray was already loaded and shurely even the file.


Secondly Pictures which need more time to pre-process then actual render
time
maybe not the best candidates for "Tiling" in Hyperthreading Systems. (=
rendering them in pieces).
(General statement)
The point is that we start 2 instances of POV-Ray and EACH does the full
Preprocessing.

If you would have a time win of 20% for using the Hyperthreading, you have a
loose
for doing the Pre-Processing two times. I have no idea if "preprocessing"
can be "hyperthreaded" or not.
On my Dual-Athlon i've found that Preprocessing produces nearly no CPU-usage
(I used PartixGen - very intresting and fully distributable) - so I would
say give it a try.

With real SMP-Systems (my Athlon here) the situation is diffrent.

2. SMPOV and the Renderagent need also some calculation- and reaction time.
   They are primarily made for pictures which need long time to render so
   the "builtin reaction-times" are rather slow to save CPU-time.
  Reaction time is, between SMPOV giving the Orders for Rendering out till
the RenderAgents react.
  Secondly till they notice that POV-Ray is ready. Then thirdly SMPOV has to
get a message that all
  the tiles are ready. And fourth it has to start PicPender.exe to "put al
lthe tiles together".
  There are several reaction times that may add up to 5 Seconds. Add your
loading times and some
  time for "Preprocessing"

3. Two instances of POV-Ray are started. (=Loading time for POV-Ray).

4. To find out where the times are, you can render it with SMPOV, make the
"Tiling" on 1
   (so there will be only 1 instance started). Then make a second try (tling
on 2) - try "H" and "V"
   there are diffrences. Then you have numbers in the log-file. These
numbers include some overhead,
   but at least you are shure the settings are really the same for all runs.

Keep me informed if you make a second try.

--Theo
-----------------------------------------------------------------------
Distributed Network-Rendering or Local SMP-Rendering. With SMPOV and
POV-Ray 3.5. * Download free at: http://www.it-berater.org/smpov.htm

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