HyperThreading, Yes or No?

[Rockas]

For the first time of my life, I'm dealing with an Intel Processor (I really had no choice :D)... this is a (HP Notebook with a nice "widescreen" :)) Pentium 4 3.2 with hyperthreading... now my question is... Working with DVD Rebuilder shall I enable or Disable HyperThreading?

[Carpo]

i have a p4 3.40 and have it enabled in the bios - and have done may encodes with it on - it does seem to help with most stuff - some say to use it some say dont - up to you really, last time i turned it off pc did seem to slow up a smidge

[lantern]

I use hyperthreading on my PC with DVD-RB and have not had any problems!

[Rockas]

Thanks! I was asking this 'cause I remember someone complaining about the Encoders not being using all the processor power!?!?!?

[johnhamler1]

what is that? dual processor???

[rendez2k]

I have hyperthreading enabled (which works great) but isn't it HC that doesn't use it?

[Boulder]

If you use CCE, you get a nice performance boost as it supports multithreading.

If you use any Avisynth filters, check out tsp's MT plugin. It'll give a very noticable boost as well:)

[Rockas]

If you use CCE, you get a nice performance boost as it supports multithreading.

If you use any Avisynth filters, check out tsp's MT plugin. It'll give a very noticable boost as well:)
Do you know if CCE 2.50 supports multithreading?

@johnhamler1
No... it's a system that simulates something like that... - Keeping it simple, of course - it takes advantage of the idle cicles of the processor.

[Rockas]

@jdobbs (if you read this :))
What is the speed you are getting from AMD 3200+ (I gues that's yours, no?) on CCE 2.50?

[Boulder]

Do you know if CCE 2.50 supports multithreading?

My guess is that it doesn't. You can see it by checking the Task Manager while encoding. If CCE's CPU usage is steadily over 50%, it utilizes two threads.

[jdobbs]

@jdobbs (if you read this :))
What is the speed you are getting from AMD 3200+ (I gues that's yours, no?) on CCE 2.50? Using CCE v2.50 I get a speed of right around 3.00x. My 3200+ is an XP processor, not to be confused with the 64 bit models. With CCE Basic v2.70 I get about 2.80x.

[jdobbs]

Do you know if CCE 2.50 supports multithreading?
My guess is that it doesn't. You can see it by checking the Task Manager while encoding. If CCE's CPU usage is steadily over 50%, it utilizes two threads.It probably began here:

Version 2.64.01.02 Tuesday, November 20, 2001

Changes
- Tuned for Dual CPU environment.

[maksa]

Working with DVD Rebuilder shall I enable or Disable HyperThreading?

I have P4 3.2 G and AMD Athlon +32 (64 bit). Running CCE on P4, system resources tells me that CPU is used 50%. Runing 2 instances of CCE I got 100% usage. Using HT I dont have any decrease in speed (in CCE) if second one is running or not.
On AMD one instance of CCE and I can not do anything else (darn slow), CPU usage is 100%, but the speed is slightly higher (1.7 v.s. 2.1 for simple AVS scripts). Important is that I am running XP on both machines and that AMD is 64 bit CPU. I believe if I get 64-bit Windows it will use full potential of Athlon ( they have something similar to HyperThreading, just can not get the name in my head).
Just my 2c...

P.S. P4 has 2 processors built in anyways.

[Boulder]

If you have a dual-core Athlon, it's the closest to HT you can get without buying a P4. I'm not sure if AMD has yet come up with a multithreading, single-core processor even as an engineering sample.

HT is the main reason I'm a P4-user, the thing that the computer isn't dead slow when doing something CPU intensive is just great. As soon as dual-core 64-bit Athlons become reasonably priced (and the 64-bit Windows is released), I'm ready to switch back to AMD systems.

[writersblock29]

@Maksa

[Qouted]: "I believe if I get 64-bit Windows it will use full potential of Athlon"

Yes, and no. All of the programs you're running currently (under 32-bit XP) are also either 32-bit or 16-bit (certain installers). 32-bit currently will run using XP64, but you theoretically won't notice a difference in performance with these programs because they'll be running on a 32-bit platform. 64-bit programs (of which there are currently few, but that number will climb eventually) will be able to fully use the AMD64's (Pentium's also jumping on the 64-bit bandwagon) full capibilities. Nice link below:

http://www.microsoft.com/windowsxp/64bit/default.mspx

I'd tried Microsoft's trial version of Windows XP64, but really couldn't run it through its paces because hardware drivers are a bit scarce. Now that I'm seeing at LEAST beta versions of 64-bit drivers on my hardware, I've thought about giving her another go.

[wfn1]

HT will improve things if you're planning on using other programs while encoding. It's just pretty much load balancing.

I wish there was a real way to do smp while using avisynth+cce but the only quasi working way i found was thru ms int filter. It basically isolates codecs, filters and plugins on one cpu while cce is running on the other. I found gains to be marginal to non-existant with that setup.

I have dual Xeon Prestonia's 2.4GHz LV @ 3.4GHz and I never see more than 30% load on my system.

[robot1]

I've just bought an Athlon 64 x2, and rebuilding with ProCoder 2 gives 70-80% cpu usage (ProCoder 2 is multithreaded).
And, best of all, I can use the PC while backing up a DVD.

[Rumbah]

That's why I wrote DualDVDRB. To make use of HT or a second processor(core). I get a speedgain of 15% using it with DVDRB and HC on a P4 3,2 Ghz.

I recently noticed that it does not work with the multiangle processing, I'll look into it, but it works for "normal" backups.

[Harrysmiith]

Thanks! I was asking this 'cause I remember someone complaining about the Encoders not being using all the processor power!?!?!?

Using HC 0.16 and Rebuilder Pro with my Pentium 4 3.2 gig cpu usage is steady on 50%. I never use this machine for anything else other than DVD work so looks like even this dated pc is not really being pushed ?

[Rockas]

Thank you all for the feedback.
meanwhile I made some tests and i got some strange results.

First of all, here's my (brand new :D) notebook:
http://h10010.www1.hp.com/wwpc/uk/en/ho/WF06b/21675-38187-38191-38191-38191-12255842-63625459.html

Now... I selected a clip from the Spiderman 2 DVD and used it for tests... I runned prepare phase on Rebuilder for both versions (CCE 2.50 Retail and CCE 2.70 Trial) and tested both with HT ON and OFF here's the results.

HyperThreading ON:
CCE 2.50
VAF creation = 0:59
M2V encoding = 0:57

CCE 2.70
VAF creation = 0:58
M2V encoding = 0:58

The processor "occupation" was always between 75% and 80%

HyperThreading OFF:
CCE 2.50
VAF creation = 1:09
M2V encoding = 1:07

CCE 2.70
VAF creation = 1:08
M2V encoding = 1:08

The processor "occupation" was always between 90% and 100%

Strange, isn't it?
With Hyperthreading Off the processor was at 100% but encoded slower!?!?!

By the way... the speed with HT on was between 2.9 and 3.4 with both versions and between 2.4 and 2.8 with HT Off.

Another note... the system parameters were equal for HT ON and HT OFF... this is a fresh installation and I kept the default applications running on the background... meaning... I haven't turn off Antivirus (Avast) nor Firewall (Sygate) or any other that may be running.

[Rockas]

@maksa
1.7 v.s. 2.1
Isn't that too slow?
I can get that speed with an old AMD XP2000+ ... without filters and two hard drives and only 768MB ram

[Boulder]

On HT systems it's normal to have 50% CPU usage when a program that doesn't utilize multithreading is running. If the program supports multithreading, the usage goes above 50% as both instances of the CPU are being used.

[Rockas]

On HT systems it's normal to have 50% CPU usage when a program that doesn't utilize multithreading is running. If the program supports multithreading, the usage goes above 50% as both instances of the CPU are being used.
I believe that but... on my test I got strange results, don't you think?
Why in the hell 80%(max) of CPU usage is quicker than 100%? Am I missing something here? Another thing... CCE 2.50 gives me the same encoding time of CCE 2.70... maybe it is multithreading and Custom Technology doesn't know that :D

[SpazzHH]

I believe that but... on my test I got strange results, don't you think?
Why in the hell 80%(max) of CPU usage is quicker than 100%? Am I missing something here?

Perhaps it's because 80% of two CPU channels is more powerful than 100% of only one.

[pilar]

@Rockas
There are different Windows kernels for single and multiprocessor PCs. You probably didn't switch them when turning off HT. Maybe that's the reason of your strange results.

Pilar

[wfn1]

pilar,
different kernels? maybe if you're talking about the old windows nt 4.0

@everyone,

Here's a small breakdown of how it works and what supports it :

win95,98,me: no smp support
win2k workstation: 2 physical cpus, no support for HT
win2k server: up to 4 physical cpus, supports HT
win2k advanced server: up to 8 physical cpus, supports HT
win2k datacenter server: up to 16 physical cpus, supports HT
winxp workstation: up to 2 physical cpus, supports HT natively
win2k3 standard: up to 2 physical cpus, supports HT natively
win2k3 enterprise: 4-8 physical cpus, supports HT natively
win2k3 datacenter: 8-32 physical cpus, supports HT natively

Although Win2k server will see your HT CPU(s) it will treat all logical processors as physical ones because it goes by the BIOS info. Therefore if your BIOS has HT enabled and reports it correctly you'll see double the physical processors in Win2k when you have HT enabled. Keep in mind that it'll need to be licenced in accordance to that quirk (2 processor licence for a single HT CPU or a 4 processor licence for a dual HT CPU and so on) Win2k Server is not as efficient as XP or 2K3 at handling HT because the latter were written with HT in mind.

HT is not real SMP, it's SMT (simultaneous multithreading) which is more like interleaving rather than actual parallel processing. The two logical processors still fight for the same bus, cache, etc. it's a kind of management and load balancing. With certain applications you can see a 10-30% gain according to Intel themselves but in other tasks you may actually suffer a performance hit. For my usage patterns I actually see a small gain in performance.

Most important thing to keep in mind is that when all other things are equal -- dual processors or dual cores will always be better for applications that support multithreading properly and even for those that don't than just a single CPU with HT.

Interesting reading:

AMD Dual core vs HT (http://www.infoworld.com/infoworld/article/05/04/21/17TCamd_1.html)
Intel Dual cores vs Intel Singles w/ HT (http://www.pcworld.com/news/article/0,aid,120656,00.asp)

[pilar]

pilar,
different kernels? maybe if you're talking about the old windows nt 4.0


No, it still aplies to XP and 2k. You can install different kernel in Device Manager/Computer/Update driver/choose from list/show all hardware.
You can run multiprocessor kernel with HT off, not sure about the uniprocessor and HT on.
I have one app that simply don't work with multiprocessor kernel regardless of HT state, but works with "standard PC" kernel (and HT off).

Pilar

[wfn1]

No, it still aplies to XP and 2k. You can install different kernel in Device Manager/Computer/Update driver/choose from list/show all hardware.
You can run multiprocessor kernel with HT off, not sure about the uniprocessor and HT on.
I have one app that simply don't work with multiprocessor kernel regardless of HT state, but works with "standard PC" kernel (and HT off).

Pilar

It's not the kernel. What you're talking about is an ACPI (advanced configuration and power interface) profile for your HAL (hardware abstraction layer) which is different for multi and single processor PCs.

Windows XP knows about HT and physical dual processors therefore it will differentiate between the actual and logical units without a problem. It will pick an appropriate profile. Moreover, WinXP's single processor HAL profile will recognize when you add a second CPU and will install proper MP files thru "found new hardware". 2K will just assume all your HT units are physical processors from the get go. That's all, in either case everything should work with default values with XP having better HT handling.

[pilar]

It's not the kernel. What you're talking about is an ACPI (advanced configuration and power interface) profile for your HAL (hardware abstraction layer) which is different for multi and single processor PCs.


Agree, but it's kernel too. Now I'm sitting at win2k PC and in system32 directory I see at least 3 different kernels with names like ntkrnlmp.exe, ntkrnlpa.exe, ntkrpamp.exe. These all are kernels, but only one is actually active, that named ntoskrnl.exe (it's stated in boot.ini "/kernel=" parameter). In my case it's the same file as ntkrnlmp.exe. During installation the right one is probably copied to ntoskrnl.exe file.
I can't check now what's active on XP machine where I was forced to switch from multiprocessor to standard one.

Pilar

[Rumbah]

You could try using perfwatch (ftp://ftp.heise.de/pub/ct/ctsi/perfwtch.zip) . It can show the internal processor load, not only the utilisation Windows shows.

[artoor]

(...)First of all, here's my (brand new :D) notebook:
http://h10010.www1.hp.com/wwpc/uk/en/ho/WF06b/21675-38187-38191-38191-38191-12255842-63625459.html (...)
Strange... they have given You Microsoft Windows XP Home Edition, but if my memory serves me right, HE doesn't support HT technology... am I right? Unless You have already reinstalled Your OS ;)

BTW - Nice machine.

[Rockas]

Strange... they have given You Microsoft Windows XP Home Edition, but if my memory serves me right, HE doesn't support HT technology... am I right? Unless You have already reinstalled Your OS ;)

BTW - Nice machine.
Home Edition doesn't support HT?
Are you sure about that?
Can anyone (with a little more knowledge about this stuff) confirm this?

[artoor]

Home Edition doesn't support HT?
Are you sure about that?
Can anyone (with a little more knowledge about this stuff) confirm this?
According to this (http://www.microsoft.com/poland/windowsxp/pytania.asp) site (polish translation of Microsoft website) Home Edition doesn't support multiprocessor. There is the question:
"Does Microsoft XP Home work at the multiprocessor hardware?"
And the Answer is:
"No. Windows XP Home doesn't support multiprocessor hardware"
But I've found interesting site here (http://www.hardwareanalysis.com/content/daily_column/article/1532/).

And a little quotation from intel's site
Surprising though was the fact that Windows XP Home Edition will also be able to profit from this, although it does not have SMP support and is unable to use more than one processor.

Microsoft* Windows* Operating System Desktop Based PCs
The following desktop operating systems include optimizations for HT Technology and are currently eligible to carry the new Intel& Pentium& 4 Processor with HT Technology logo:
Microsoft* Windows* XP Professional Edition
Microsoft* Windows* XP Home Edition

The following desktop operating systems are not recommended for use with Hyper-Threading Technology. If you are using one of the following desktop operating systems, it is advised that you should disable Hyper-Threading Technology in the system BIOS Setup program:

Microsoft Windows 2000 (all versions)
Microsoft Windows NT* 4.0
Microsoft Windows Me
Microsoft Windows 98
Microsoft Windows 98 SE
Maybe it'll be helpfull for You :) If not, sorry for confusion. I don't even know... maybe it isn't important for You... hmmm...

Regards

[jdobbs]

I believe the Home Edition will only support one physical processor but will support two logical processors...

[lantern]

I have XP Home Edition installed with Hyperthreading enabled and it works just fine. You can see that hyperthreading is enabled in the Device Manager under processors. There will be two processors listed. WinXP Home only supports one physical processor.

Here is a link to Microsoft Support (http://support.microsoft.com/default.aspx?scid=kb;en-us;810231):

http://support.microsoft.com/default.aspx?scid=kb;en-us;810231

[artoor]

Okay... my mistake... sorry. Here is a piece of information about it => http://support.microsoft.com/default.aspx?scid=kb;en-us;810231

--==EDIT==--

@lantern

You've forestalled me :)

[Rockas]

Thank God!
Thank you guys :)

[Sophoclesdrf]

Rockas

CCE is not compatible with Hyperthreading even though CCE is smp ready. In order for Hyperthreading to work the CPU must have some unused CPU cycles that can then be divided into a separate processing thread. CCE however uses all of the available CPU cycles in a single thread so there's nothing left to allow for processing on a separate thread. In some cases Hyper threading might actually slow down encoding or processing when using an SMP ready CPU intensive application. I haven't however heard of any slow downs but it is doubtful that there will be any speed gains using CCE and hyperthreading.

Here a link to CCE's web site stating that CCE receives no benefit from hyper threading.

http://www.cinemacraft.com/eng/faq_offline.html#01

Rockas

I missed this point. Windows Xhome edition doesn't support more than one processor but it does support hyper threading.

http://support.microsoft.com/default.aspx?scid=kb;en-us;810231

[Rockas]

@Sophoclesdrf
Well... in the little test I made, HT made CCE work faster even with a less use on the processor... this makes it even stranger :)

[Sophoclesdrf]

The differences in your times from 59 minutes to 109 minutes are greater than those found using dual core or dual proc systems. Knowing you I believe your results but something has to be awry. A member of www.dvdhounds.com (you know 6402) has an AMD X2 3800 plus overclocked from 2.0 ghz to 2.65 Ghz and he's only seeing a 30% increase. In a test the X2 3800 at stock speeds should with smp software, walk all over any single core Intel chip and it even beats Intel's lower dual cores too. I don't know a lot about your laptop but processors installed into laptops usually have a built in governor system that lowers the CPU requirements based on need. Usually hyperthreading used with CPU intensive smp ready applications see a slow down. I would be interested in any future testing that you do.

[Rockas]

My next test will include full DVD Backup... that will be more elucidative :)

[J-Wo]

I am thinking of doing a hardware upgrade in the new year. Currently I have an Athlon XP 2500+ overclocked to 3200+. My primary usages are video encoding (DVDRB, CCE, HC) and games. I read some reviews on gaming sites which recommended the Athlon 64 X2 4400+. Will encoders like CCE or HC utilize the dual core of the 64 X2 in WinXP Pro? Will they only use 50% CPU load allowing me to use other programs, or will they use both CPUs, maxing me at 100% but essentially doubling my encoding speed?

If anyone has some good links to CPU reviews with some video encoding benchmarks/comparisons etc., that would be greatly appreciated!

[geezer]

@J-Wo

Have you seen this one?

http://www.tomshardware.com/2005/11/21/the_mother_of_all_cpu_charts_2005/index.html

[Sophoclesdrf]

J-Wo

I too was looking at purchasing the X2 4400 and would have except for the fact that the Opteron 175 dual core is almost the same price so I went with it instead. CCE is smp ready and yes you do see a significant speed gain. What I find strange is the speed difference between CCE SP 2.67 and 2.70.2.1. With version 2.67 I was averaging encode speeds of 5.5 to 6 times but what is interesting about 2.70.2.1 is that it starts with about the same speed as 2.67 for the first pass but the second pass kicks into warp speed of 11 to 13 times. This is giving me about a 12 to 15 minute gain over version 2.67 and my encodes prepare/encode/rebuild are all coming in under 50 minutes.