Alegria



My thoughts exactly and the reason why I did not agree with Scott to begin with. Also, the recent research I've done on this subject simply confirms it without a doubt. HPET OFF is not a tweak nor is it a "one size fits-all" fix for systems having trouble with a high precision external clock. And as mentioned by Goddard...,
"

 
[size=4 font="times new roman"]What research? Please show me anywhere with data that shows the HPET increases performance with anything. I have seen the opposite every time with Pro Audio. Boards that were unusable for audio below a 256 Buffer could now handle a 64 Buffer with the same interfaces. Laptops by default do not have the option to disable HPET in the bios so that is something we still have to convince the manufacturer to do when needed. What I can say is when I have shown the systemboard engineers the DPC screen pics and the links to the programs we use to get those, the first bios I get back is the option to turn off the HPET. I wonder why that is?
 
BTW please dont look at White Papers from 2006 to 2008 and think the evolution of that technology ends there. How do you think they are implementing live bios changes to EFI bios's without using the IME/AMT. They are integral to those as well as updating Firmware level power management that comes with laptops on the keyboard firmware as well as system bios. The Intel Management Engine was actually introduced first on laptops in the Core2 days. Intel and the laptop manufacturers stated the IME driver used was modified and specific to the laptop manufacturers as they required. Intel creates guidelines with the IME and then allows the manufacturers to change as required. That is definitely how it's done currently as EFI bios features expand. Dont assume 1 white paper from years before the platform tells you exactly how that technology is implemented now.
 
Eric
ADK

"jcschild"
ok now that we got all this technical crap posted and out of the way..

Fact: accross MULTIPLE motherboards from varied manufacturers, and with both socket 2011 and 1155
and every processor that can go into them..

HPET OFF = less DPC
HPET ON = more DPC, and in fact can be very detrimental with certain video cards.. also has much to do with PCI cards working particularly Lynx on P67 

period end of discussion, on each and every combo.

No, this is not the end of the discussion because you say so. And you certainly don't take into account all system configurations such as dedicated DAWS (audio only). HPET adds a minute amount of latency simply because it's an external clock. This is well documented and also applicable to LAPIC. But on the order of what magnitude? This is something that I can answer confidently. Can you?

HPET adds a minute amount of latency simply because it's an external clock. This is well documented and also applicable to LAPIC. But on the order of what magnitude?

 
 
There is a inherent increase in DPC activity just from the HPET. That latency fluctuates on average between 350us and 150us higher than it is when turned off. This also varies by board, platform, and desktop versus mobile because of further firmware implemented on mobile. Normally this activity is not enough to cause issues with audio accept at a buffer below 64 on most interfaces or 128 on some. The real problems are any spikes that increase the activity more then 350us and often those are hardware effected by the HPET. The boards that show these issues have spikes upwards of 21,000us often replicating every second to 5 seconds. Disabling the HPET reduces these either to sub 5000us or often eliminates them completely depending on the driver/bios. That is how much activity HPET is initiating with those devices while it's active. On those same boards, the DPC activity would also completely go away down to sub 20us if the C-States and Turbo was disabled. All of this is far more than the original DPC activity HPET initiated alone.
 
Eric
ADK

Ah, I just found the definition of a dedicated DAW for professional Audio use.

They seem to have a wide range, I wonder if they come with HPET on or off.  I also wonder if they have core parking enabled.

http://adkproaudio.com/

"ECBowen"
There is a inherent increase in DPC activity just from the HPET. That latency fluctuates on average between 350us and 150us higher than it is when turned off.

In my case, it's no more than approx. 15us. Quite the discrepancy. 

"Jonbouy"
I want to run my audio software without glitches not have a machine that's optimized to run DPC latency checker like some here enjoy doing.

I run my audio software without glitches and HPET on. I actually run demanding libraries (24 bit) in real time with HPET on. And the ensued smoothness is..., well it needs to be experienced. But as I've mentioned before, this is not something you can do..., simply because of the nature of your multi-purpose machine and the insane amount of overhead created by the greenness of it. To each his own.

The "DPC latency checker" btw. is not a benchmarking tool but rather a diagnostic tool that display spikes in real time. Along with the "Latency Monitor" which goes many steps further in identifying processes that may be causing these spikes, they are tools to help you in this regard, no more no less.

Good day gentlemen. 

In my case, it's no more than approx. 15us. Quite the discrepancy

 
Then you must have C-States and Turbo disabled. The numbers I gave were with Turbo active. I stated before you will get similar DPC activity with the current platforms with C-States and turbo off.
 
Eric
ADK

"ECBowen"
Then you must have C-States and Turbo disabled.

Of course, and then some..., and then some more. I don't even have my DVD drive on at all times, disabled in computer management along with "cdrom.sys" which is disabled with the help of SysInternals "Autoruns". And I could go on and on, but I think you get the idea.

"jcschild"
again unless you have the database we do which i know you dont, subject closed.. feel free to debate with yourself no one trust me no one will be listening.

pretty sure i can guess as to who people will listen to.

Again, you're missing the point Scott. HPET off is not a tweak and certainly not for everyone, it's a workaround at best (and I don't discourage its use, especially for laptop users for example). But for those who are really serious about a non-oc'ed, non-green, non-internet'ed no nonsense dedicated DAW for audio only, HPET on is my recommendation. And I certainly don't have any problems with people listening to whoever they want to listen to.

Alegria

But as I've mentioned before, this is not something you can do..., simply because of the nature of your multi-purpose machine and the insane amount of overhead created by the greenness of it. To each his own.

Not to mention upwards of an extra .4Ghz on CPU speed without an O/C...

Nothing green about this machine except when it's not in use, not to mention the fact that I can collaborate on it without having to re-configure the thing from it's user crippled state in order to do so.

That probably wouldn't concern you though as usually you'd need freinds or colleagues in order to partake in a collaboration...

I never reach the point where I have to disable the network nor CD rom for that matter, if I did I probably will be due to upgrade.

Alegria

But for those who are really serious about a non-oc'ed, non-green, non-internet'ed no nonsense dedicated DAW for audio only, HPET on is my recommendation.

So you are saying that Scott and Eric don't produce hardware for the serious dedicated DAW user?  And you are the serious one?

I'm not offering any recommendation but if you want to leverage the best low latency performance out of your machine and have it running at it's full potential, you'll likely find you are much better with it off.

You are right of course Scott.

I just know how much damage these type of self-appointed 'experts' can cause.  Like I said earlier he will likely be employing every bit of knowledge gained here and passing it all off as his own 'genuis' further down the line.

It just made me gag this time and I've already engaged far more than I'd wanted to.

Hilarious bull Jonbouy!

and am having various annoyances with the windows 8 partition.

Windows 8 may well be another issue altogether with HPET.  I noticed somewhere that LAPIC has been dropped altogether so some changes have certainly been made.

What's the official release date on 8 now?  It must be pretty soon.

I'm likely to take your approach and put it on another partition for testing until I can get it performing as least as well as 7 currently is.  I'm not in a rush to migrate when stuff is already working great.  LOL I've only just relinquished my last little dependencies on XP so I'll probably put 8 on that partition now.

that thread is just like this thread..

1 guy who thinks he has an answer and everyone else saying nope made it worse... hmmm.
not to mention its about gaming. there are tweaks i would do for gaming i would NOT do for audio/video..

last post in this 4 pages of useless thread..

I support windows comps for a bunch of small companies, organizations and individuals.

Got a mix of wXP, wV, w7, and soon to be w8. So am getting ready for what will come: new installs, upgrades, new hardware,....

On my music computer I have 3 partitions on the OS disk: w7-32, w7-64, and w8-64.


I have attempted to follow the various ideas/approaches in this thread.

The idea that drivers interfere with each other seems to be key to clarifying the differences experienced with the various tweaks used by us all. The linked thread interates the problem with stuff interacting.

Fur shur there are hundreds of thousands of processes happening when a computer is running. All kinds of stupid **** occurs because of the thousands of combinations of hardware and drivers. Very complex. Way underestimated by most people.

I want anything that is not of use to not be started/running.

New computers' speed can make many tweaks of the past irrelevant. 
And mask issues that only head-their-ugly-rears when least appreciated.

But I still do some tweaks just for grins.

The link has an interesting description of the need for HPET to be the lone timer.  

As usual some confuse startup speed with application performance.

No doubt the conflict caused by multiple timers is a clue for some annoyances.

j