Why does Rebuilder use so much CPU during encoding?

[idbirch2]

If I check Task Manager once encoding has started (with CCE 2.67.00.23) Rebuilder.exe will sit there using 15-25% CPU which obviously slows CCE down considerably. Why is this? Do I have to close Rebuilder and start encoding manually from CCE or what? I can't understand why Rebuilder.exe needs 25% usage of a Pentium 4 Prescott 2.8! What is Rebuilder doing that requires this amount of power? I thought once encoding has started CCE does all the work?

Very confused :confused: :confused: :confused:

[wmansir]

It's from monitoring CCE. I believe it was found to be particularly high on P4s with HyperThreading. I know jdobbs has talked about trying to reduce CPU usage in general, but I don't know if he specifically referred to the HT issue. I know he mentioned having an AMD CPU, so it could take a while.

[DDogg]

CCE .027 allows the whole ecl to be loaded as one go. So that may be an intermediate solution, although slightly manual.

[quantum]

Why not try RB Farm just on the local PC and see if the CPU usage is the same? If it's improved, I can pass the polling code on to jdobbs.

[idbirch2]

Originally posted by DDogg
CCE .027 allows the whole ecl to be loaded as one go. So that may be an intermediate solution, although slightly manual.

Hasn't DVD-RB now been changed so it encodes each cell individually rather then making one big *.ecl file? This means I have to keep DVD-RB open during encoding doesn't it?



It's from monitoring CCE. I believe it was found to be particularly high on P4s with HyperThreading. I know jdobbs has talked about trying to reduce CPU usage in general, but I don't know if he specifically referred to the HT issue. I know he mentioned having an AMD CPU, so it could take a while.

Dang I guess I'll have to take a hit on encoding times till it gets fixed then :(

[Joergen]

Originally posted by idbirch2
Hasn't DVD-RB now been changed so it encodes each cell individually rather then making one big *.ecl file? This means I have to keep DVD-RB open during encoding doesn't it?





Dang I guess I'll have to take a hit on encoding times till it gets fixed then :(

idbirch2: cant you switch HT off in your bios?

[DDogg]

I just mentioned it because the REBUILDER.ECL holds all of the individual segments. An ecl can hold multiple encodes, it doesn't have to be just one. Before CCE 2.67.00.27, CCE would just crash if you tried to load the complete rebuilder.ecl which holds many, many jobs. There was a memory problem bug. Now, a person with this newest version of CCE could, I suppose, manually load the one ecl and let CCE do its thing. However, I have not tried it. You might have to change some pointer in dvd-rb to allow the rebuilding option to be available. Frankly, I probably should not have mentioned it since I had not actually tried it.

[idbirch2]

Originally posted by Joergen
idbirch2: cant you switch HT off in your bios?

Yes I could but I don't want to :D

[quantum]

Originally posted by DDogg
CCE do its thing. However, I have not tried it. You might have to change some pointer in dvd-rb to allow the rebuilding option to be available. Frankly, I probably should not have mentioned it since I had not actually tried it. I tried it, and it works. At least I loaded the big ECL and confirmed the memory problem was gone. I didn't actually compile a job, but I bet it will work. You would have to edit the rebuilder.inf manually after the encode and change Progress=1 to Progress=2.

[idbirch2]

Version 0.46 still uses 15-20% CPU on my P4 Prescott 2.8GHz :(

[DDogg]

This is probably wasting your time, but you do have RB set on low priority? I still have to do that when CCE is on low. I noticed speed dropped from 2.85 to 2.39 when I did not keep it on LP when CCE was LP. 'Course this is on my AMD, so it probably has nothing to do with what you are experiencing.

[jdobbs]

Originally posted by idbirch2
Version 0.46 still uses 15-20% CPU on my P4 Prescott 2.8GHz :( I'll change it again in 0.47 and see what happens.

[idbirch2]

DDogg - worth suggesting but no, setting to low priority makes no difference however if I right-click Rebuilder.exe in Task Manager and then 'Set Affinity' I can assign Rebuilder to just a single CPU instead of both (not really 2 CPUs, I know) and this drops it right down to 0-1% usage. Anyway of making DVD-RB starting itself set to only 1 CPU on dualie/HT systems?

[borgraf]

Originally posted by idbirch2
Anyway of making DVD-RB starting itself set to only 1 CPU on dualie/HT systems?
I tested this before and can confirm that disabling one (virtual) cpu for DVD-RB does make CCE jump to ~99% cpu usage. Unfortunately, when DVD-RB is assigned 1 cpu and launches other progs I think they will also be assigned 1 cpu. So we won't get the benefits of HT from CCE using that method.

Edit: There is the dirty way of starting off using both cpu, launc CCE and then set DVD-RB to use only 1 cpu. Then set back to using both before launching the next instance of CCE.. Et cetera.

[idbirch2]

Originally posted by borgraf
Unfortunately, when DVD-RB is assigned 1 cpu and launches other progs I think they will also be assigned 1 cpu. So we won't get the benefits of HT from CCE using that method.

borgraf is spot on - assigning DVD-RB only 1 CPU does stop it munching so much CPU but subsequent CCE jobs launched by DVD-RB have CCE assigned 1 CPU aswell. This is even worse than letting DVD-RB use both CPUs as encoding speed is halved.

I don't quite understand why DVD-RB needs any CPU during encoding - what is it actually doing? I use the Big3 a lot and DoCCE4U/BatchCCEws send jobs to CCE without consuming any CPU time at all. I am aware that jdobbs has an AMD so can't really test this properly and this probably isn't anwhere near the top of the list of bugs to fix but in the mean time would it be possible to have a check-box which HT users can enable to stop DVD-RB doing whatever its doing while CCE is going?

On a better note, whatever jdobbs changed between 0.44 and 0.46 has fixed my error #0004s!!

[DDogg]

I believe jdobbs just expects us all to do our homework and make a specific recommendation to him without him being required to do all the time consuming research. You guys did that, so hopefully if it is doable, he now has something specific to try. I think this is a great way to handle individual issues.

[BBWoof]

Hey jdobbs,

I've been using DVD-RB for doing TV Show dvds, and the results have been great. I'm mightly impressed.

I've also been monitoring the CPU usage on my machine. I'm running XP Pro on an Intel 2.8GHz processor with multithreading turned on and DVD-RB 0.46. For me DVD-RB shows anywhere from 20%-35% of usage while CCE is running.

It's been a long time since I programmed with VB so I don't really remember, but does it allow for custom windows messages to be created. With BatchCCE I've created a thread to monitor CCE, and when complete it sends a WM message to the main app. It's made the CPU usage almost nothing. I was wondering if something similiar was available that could be implemented in DVD-RB.

BBWoof

[idbirch2]

Version 0.47 seems to have fixed the problem - Rebuilder.exe now uses 0-1% CPU - thanks jdobbs! :D