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Upgrade to 4.6/1.6 -- Major Drop in FPS

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→Started 2 years ago by Adam Kendall
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Adam Kendall

I'm going to report this problem the way everyone hates -- General vague statement with no supporting patch, details, etc. But I don't know how else to do it.

I'm on XP, on a Dell 6400 laptop. Core2Duo 2.16. 2Gb RAM. Radeon x1400. QuickTime 6.5.1

I *was* running Max 4.5.x/Jitter 1.5.x

Everything was great.

Over the weekend, upgraded to 4.6.2/1.6.2

All my Jitter apps had a major drop in FPS, approx. 40-50% drop.

I thought it meant only a single processor was being used, but in Windows Task Manager, I could see both being utilized.

My patches are all QT-based (no OpenGL). No slabs. Performance Settings didn't make a difference.

Reverted to 4.5.x/1.5.x, everything's back to normal, i.e., got my FPS back.

Any ideas? I can't post patches, because my "apps" are too dense with subpatches.

Any checklists for me to over with 4.6.x/1.6.x? Do I need the a different version of QT? What's the message to explicitly tell the computer to use both CPUs? (Task Manager said both were working, but maybe I should be explicit to be safe?). Are there any known problems I didn't find in my searches?

Any guidance appreciated.

2 years ago
Jeremy Bernstein

One change which might be affecting you: hiquality is on by default
in jit.qt.movie, whereas it wasn't before. Depending on your media,
this could affect your output rate.

jb

Am 03.04.2007 um 14:15 schrieb Adam Kendall:

> Any ideas? I can't post patches, because my "apps" are too dense
> with subpatches.
>
> Any checklists for me to over with 4.6.x/1.6.x? Do I need the a
> different version of QT? What's the message to explicitly tell the
> computer to use both CPUs? (Task Manager said both were working,
> but maybe I should be explicit to be safe?). Are there any known
> problems I didn't find in my searches?

2 years ago
Adam Kendall

Thanks, Jeremy, I'll try that when I have time to reinstall 4.6/1.6

Adam

2 years ago
Mattijs

Quote: Adam Kendall wrote on Tue, 03 April 2007 14:15
----------------------------------------------------
> What's the message to explicitly tell the computer to use both CPUs? (Task Manager said both were working, but maybe I should be explicit to be safe?).

Jitter and Max together use only one cpu, except for certain 2D processing objects. Have a look at this:
http://www.cycling74.com/forums/index.php?t=msg&goto=78171&rid=3579&S=266c595fbb6d78dcb5fdfea86037a9a2#msg_78171

Mattijs

2 years ago
Adam Kendall

I can only respond with my personal experience (which is all 2D video, no OpenGL) -- Both my processors are used, and the load is distributed pretty evenly among the two.

When I switched from a single-core P4 3.x ghz chip to a Core2Duo 2.x ghz chip, my FPS were noticeably higher on the same patches.

There is a "message to max" to explicitly tell Max to use n processors. I played around with it when I got my Core2Duo.

Cycling told me at the time that Max may not automatically recognize the two processors, though in my experience it did.

I want to emphasize that my Jitter work is all 2D, I don't know how Jitter handles multiple processors with 3D.

Adam

2 years ago
Mattijs

Quote: Adam Kendall wrote on Sat, 07 April 2007 23:49
----------------------------------------------------
> I want to emphasize that my Jitter work is all 2D, I don't know how Jitter handles multiple processors with 3D.
>

Yeah, certain '2D' (matrix processing) objects make good use of multiple processors, although I don't know where to find the list of which objects do and which don't. Still, the actual message passing system of max itsself is done in one thread, thus running on a maximum 100% of one cpu.

Note that this doesn't mean that you'll see one cpu using 100% and others 0% in your cpu monitor. The workload will be done alternately on different cpu's, but only one at a time. A cpu monitor usually displays an average and will make it seem that with two processors, your framerate will start to drop when the cpu load reaches exactly 50% at both processors.

Mattijs

2 years ago
Wetterberg

Adam Kendall skrev:
> There is a "message to max" to explicitly tell Max to use n processors. I played around with it when I got my Core2Duo.
Hi Adam, could you elaborate on this a bit? It's news to me...

Thanks,
Andreas.

2 years ago
Adam Kendall

Quote: Mattijs wrote on Sat, 07 April 2007 16:10

> Note that this doesn't mean that you'll see one cpu using 100%
>and others 0% in your cpu monitor. The workload will be done
>alternately on different cpu's, but only one at a time. A cpu
>monitor usually displays an average and will make it seem that
>with two processors, your framerate will start to drop when the
>cpu load reaches exactly 50% at both processors.

Ok, I see.

Adam

2 years ago
Adam Kendall

Quote: Wetterberg wrote on Sat, 07 April 2007 16:14
----------------------------------------------------

> Hi Adam, could you elaborate on this a bit? It's news to me...
>

I don't know what else to say about it -- Cycling pointed me to a message that explicitly tells Max how many CPUs to use. I can't find the message anywhere, even though I played around with it in September. In my experience on XP, Max defaults to using both CPUs without prodding.

Adam

2 years ago
Johnny deKam

The Max Topics pdf page 106-115 documents the 'messages to max'
available - but surely there are a number of 'undocumented' messages
(the use of processors for example) -- also, there are some messages
that can be sent to the jitter kernel, but i've found no
documentation of these (?) It would be great if someone at c74
could create a list of pertinent undocumented kernel messages that
might help intrepid users.

thanks

deKam

> I don't know what else to say about it -- Cycling pointed me to a
> message that explicitly tells Max how many CPUs to use. I can't
> find the message anywhere, even though I played around with it in
> September. In my experience on XP, Max defaults to using both CPUs
> without prodding.
>
> Adam

2 years ago
vade

guys! html docs!

http://cycling74.com/documentation/group-mess-jitter

:)

parallel [0/1 (int)]
Turns parallel processor support on/off. Default is on if machine has
multiple processors (or cores), and otherwise off.

parallelthreads [threadcount (int)]
Specifies the number of threads used for parallel processor support.
Default is the number of processors (or cores).

parallelthresh [threshold (int)]
Specifies matrix cellcount above which parallel processors are used.
Default is 10000 cells.

On Apr 8, 2007, at 12:57 PM, dekam wrote:

> The Max Topics pdf page 106-115 documents the 'messages to max'
> available - but surely there are a number of 'undocumented'
> messages (the use of processors for example) -- also, there are
> some messages that can be sent to the jitter kernel, but i've found
> no documentation of these (?) It would be great if someone at c74
> could create a list of pertinent undocumented kernel messages that
> might help intrepid users.
>
> thanks
>
> deKam
>
>
>
>
>> I don't know what else to say about it -- Cycling pointed me to a
>> message that explicitly tells Max how many CPUs to use. I can't
>> find the message anywhere, even though I played around with it in
>> September. In my experience on XP, Max defaults to using both
>> CPUs without prodding.
>>
>> Adam
>

v a d e //

http://www.vade.info
abstrakt.vade.info

2 years ago
Johnny deKam

ahso thanks vade - html who would have thunk it ; )

ok - so what happens if we increase the threadcount or thresh?
say 8 threads on a dual core?
or 1000 cells instead of 10k?

-dek

> guys! html docs!
>
> http://cycling74.com/documentation/group-mess-jitter
>
> :)
>
> parallel [0/1 (int)]
> Turns parallel processor support on/off. Default is on if machine
> has multiple processors (or cores), and otherwise off.
>
> parallelthreads [threadcount (int)]
> Specifies the number of threads used for parallel processor
> support. Default is the number of processors (or cores).
>
> parallelthresh [threshold (int)]
> Specifies matrix cellcount above which parallel processors are
> used. Default is 10000 cells.
>
>
>

2 years ago
Adam Kendall

Thanks Anton.

2 years ago

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