 |
|
|
|
|
|
| |
| |
|
|
|
|
| |
| |
|
|
"Gilles Fedak" <fed### [at] lri fr> wrote in message
news:3AA8F99B.3697F6F9@lri.fr...
>
Sigh - as C.H. has pointed out, there are a few problems.
Suggestions:
Apart from excluding any files with i/o operations, you would probably want
to test-parse any files on the server and only distribute those files that
parsed within a fixed time limit. You might also want to exclude any files
over a certain file size.
You would need to exclude files with radiosity (or warn submitters that the
results will be unreliable).
Still, this could be very nice for some kinds of scenes, such as nice big
isosurfaces or photons.
If you get far enough, I'd be happy to donate some cycles - provided you can
ensure that file i/o is prevented (didn't the guy who runs the render farm
have problems with some bu%$er submitting a pov-virus?)
should it be bu%%er or is bu$%er okay?
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Tom Melly wrote:
>
> "Gilles Fedak" <fed### [at] lrifr> wrote in message
> news:3AA8F99B.3697F6F9@lri.fr...
> >
>
> <SNIP>
>
> This sound great!
>
> What version are you going to run? Also, presumably you won't allow any
> external files (image maps and hfs, etc.) or i/o access.
Well, we can support several versions as I understand there are
currently two main versions of PovRay, PovRay 3.1 and Patched or
MegaovRay.
Concerning I/O, actually we work as this: if you want to submit a task
(of an application in general) you give a file which is the stdin file,
a zip file which is a compressed directory containing all the files
requested for the execution of the task, and the command line.
The worker (remote PC) unzips the dir, jumps into, execute the command
line, inject the stdin file. So you see that's it is quite simple and ad
hoc. Right now we don't support some kind of "throttle" mecanism for
limiting bandwith, or size of
the genrated files.
> BTW, is everyone in France called Gilles? ;)
No, we have Jacques Pierre Paul etc...
Gilles Equipe Architectures Paralleles Tel 33 01-69-15-42-25
FEDAK LRI bat 490 Fax 33 01-69-15-65-86
------ Universite Paris-Sud email: fed### [at] lrifr
XtremWeb F-91405 ORSAY Cedex http://www.lri.fr/~fedak
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Christoph Hormann wrote:
>
> Gilles Fedak wrote:
> >
>
> One problem is that many povray scenes that take long to render also use
> quite a lot of memory. You must whve th whole scene on each computer
> involved and therefore need a lot of memory or you have to split up the
> rendering process itself which would result in a lot of network traffic.
Well, our first thought was to support animation rather than big and
complex scene.
Idea is that animation for wich the calculation of each frame takes few
(up to 10) hours would certainly be
the best suited calculation. It is clear that over Internet, you cannot
think of a parallelisation
of PovRay a la PVM. So maybe, in a fisrt case, only some scene with
strict requirements would be authorize.
How much memory consumes PovRay ?
--
Gilles Equipe Architectures Paralleles Tel 33 01-69-15-42-25
FEDAK LRI bat 490 Fax 33 01-69-15-65-86
------ Universite Paris-Sud email: fed### [at] lrifr
XtremWeb F-91405 ORSAY Cedex http://www.lri.fr/~fedak
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Tom Melly wrote:
>
> Suggestions:
> Apart from excluding any files with i/o operations, you would probably want
> to test-parse any files on the server and only distribute those files that
> parsed within a fixed time limit.
Exectly, this is our current work in progress :) I have contacted one of
the PovRay farm Render to get some of their scripts, if they have some.
But I didn't get any response. So what we are doing now it's first we
split an animation in calculation of frames and one task=one frame. So
we're looking for this kind of scripts, even now part are already done.
For the i/o point of view, we can easly restrict the size of the input
file to few Ko :)
> You might also want to exclude any files
> over a certain file size.
> You would need to exclude files with radiosity (or warn submitters that the
> results will be unreliable).
Ah, ok I don't know that problem. Why should we exclude radiosity.
> Still, this could be very nice for some kinds of scenes, such as nice big
> isosurfaces or photons.
>
> If you get far enough, I'd be happy to donate some cycles
Thank you very much :) I hope you will !
> - provided you can
> ensure that file i/o is prevented (didn't the guy who runs the render farm
> have problems with some bu%$er submitting a pov-virus?)
Gasp, do you mean some kind of buffer overrun in the parameterS? We
think about using
sndboxing technique like subterfugue
(http://subterfugue.sourceforge.net/). But right now it is not implented
but we can restrict the user able to submit task. You're right it is a
big issue.
> should it be bu%%er or is bu$%er okay?
--
Gilles Equipe Architectures Paralleles Tel 33 01-69-15-42-25
FEDAK LRI bat 490 Fax 33 01-69-15-65-86
------ Universite Paris-Sud email: fed### [at] lrifr
XtremWeb F-91405 ORSAY Cedex http://www.lri.fr/~fedak
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Gilles Fedak wrote:
>
> Well, our first thought was to support animation rather than big and
> complex scene.
Might have a look at:
http://sabix.etdv.ruhr-uni-bochum.de/RenderFarm/
> Idea is that animation for wich the calculation of each frame takes few
> (up to 10) hours would certainly be
> the best suited calculation. It is clear that over Internet, you cannot
> think of a parallelisation
> of PovRay a la PVM. So maybe, in a fisrt case, only some scene with
> strict requirements would be authorize.
>
> How much memory consumes PovRay ?
>
Povray itself nearly nothing, but when rendering, scenes can easily
require a lot.
Christoph
--
Christoph Hormann <chr### [at] gmxde>
IsoWood include, radiosity tutorial, TransSkin and other
things on: http://www.schunter.etc.tu-bs.de/~chris/
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
On Fri, 09 Mar 2001 19:47:45 +0100, Gilles Fedak wrote:
>> - provided you can
>> ensure that file i/o is prevented (didn't the guy who runs the render farm
>> have problems with some bu%$er submitting a pov-virus?)
>
>Gasp, do you mean some kind of buffer overrun in the parameterS? We
Nothing so difficult as a buffer overrun. He's talking about things like
#fopen, #fwrite, etc. and the pre/post frame shellouts.
--
Ron Parker http://www2.fwi.com/~parkerr/traces.html
My opinions. Mine. Not anyone else's.
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Assuming you had a sufficient number of users running the client, I would
like to see this split single frames into different rendering jobs, then
stitch the image back together when it was done.
For example, I have a set of four machines (450, 500, 702, 822MHz), and I
have one scene which takes these machines three solid days to render, and
I've only done a low quality image so far: 640x480, no animation, no AA,
povwin set to highest priority (there's a lot of glass involved). That's
about 280 hours, about 30 minutes per line. With 480 clients out there on
the net, I could have my image in a half hour instead of 3 days...
I don't recommend this in place of animation rendering, but rather in
addition to it. In fact, it would be just as beneficial to animation tasks.
Elsewhere this conversation had turned to hacking, and you should pretty
much assume this will instantly fall under attack as soon as it is publicly
available. The world is full of deviants, and it looks like a lot of them
own computers now. As was already mentioned, file IO would be an issue, but
worse than that, you will see people purposely return false results. The
SETI project had a terrible time with that. Imagine, you send off your
wonderfully detailed Louvre script, and you get back an image of Miss
November. (Ok, maybe it wouldn't be completely bad, but...)
As far as I can tell, there wouldn't be a way to really detect a
false-results hack, unless the system maybe randomly submitted test renders
to clients (with a known one-row return image) to see who wasn't behaving
and killed their account if they sent back gibberish.
Also, denial attacks will be common -- particularly in the case of something
like POV, it wouldn't take much effort to submit a bunch of files that would
effectively prevent anybody from ever getting anything else processed. The
script I mentioned earlier takes about two hours to render as just a 160x100
thumbnail and lengthy rendering times definitely wasn't my goal...
Actually, to bring this commentary full-circle, I bet farming out rendering
as single-line tasks would do much to alleviate the false-results problem.
It simply wouldn't be much "fun" for a hacker to just mess up one row in a
1200-line image, and the script owner could perhaps re-submit a single line
for re-rendering.
--j.
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
"Gilles Fedak" <fed### [at] lrifr> wrote in message
news:3AA91F44.CF4CF8F6@lri.fr...
> Tom Melly wrote:
> > What version are you going to run? Also, presumably you won't
> > allow any external files (image maps and hfs, etc.) or i/o
> > access.
> Well, we can support several versions as I understand there are
> currently two main versions of PovRay, PovRay 3.1 and Patched or
> MegaovRay.
At least three versions of MegaPOV.. :-) Things like particle
systems, cloth simulation, procedural texturing, aren't there yet..
> Concerning I/O, actually we work as this: if you want to submit a
> task (of an application in general) you give a file which is the
> stdin file, a zip file which is a compressed directory containing
> all the files requested for the execution of the task, and the
> command line.
The issue here is that Povray in and of itself allows you to
directly open files, execute command, etc..
> The worker (remote PC) unzips the dir, jumps into, execute the
> command line, inject the stdin file. So you see that's it is quite
> simple and ad hoc. Right now we don't support some kind of
> "throttle" mecanism for limiting bandwith, or size of
> the genrated files.
But thats the kicker.. I can then have a script that opens any
file, and can read and write from/to it. I could make a .rhosts
entry.. :-(
-----BEGIN PGP SIGNATURE-----
Version: PGPfreeware 7.0.3 for non-commercial use <http://www.pgp.com>
iQA/AwUBOqk1bE93h3x1fgJJEQLDrwCg5684QC55mgMyAZlxMQBFtxpFgnwAn1Eq
Uu/AnXhDpxS+w1Qo+spA+Bl5
=A2kd
-----END PGP SIGNATURE-----
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
I appreciate your considering POV, but I wouldn't use this. It's way too
dangerous, and would take too much of my resources.
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Gilles Fedak wrote:
>
> For the i/o point of view, we can easly restrict the size of the input
> file to few Ko :)
>
Restricting the size of the input file is not enough, because even a tiny input
file can easily generate a massive scene if it uses iterative elements such as
loops and recursive macros. Disallowing such elements is probably not an option,
because many people rely on them quite heavily.
As far as I can see, running a parse test on the server is the only reliable way
of evaluating a submitted scene. The test sould check that both parse time and
(more importantly IMO) memory usage are within acceptable limits. Of course with
animations, a test parse must be performed for every frame, because different
clock values can execute different branches in the script. All this may or may
not put too much stress on the server...
--
Margus Ramst
Personal e-mail: mar### [at] peakeduee
TAG (Team Assistance Group) e-mail: mar### [at] tagpovrayorg
Home page http://www.hot.ee/margusrt
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
|
|
