Topic: Dual-core Multiprocessing question

@H-man wrote:

I have inlcuded a picture of my rig running Podium under load. As you can see Podium is maxed out however the Task Manager reports differntly …quite differently 😕

When I read your post I initially thought the “Release drivers when Podium does not have focus” option was giving you (and me) a false positive. But even when I disabled this option Podium is showing 50% on a 68 track arrangement but only 25% on my Windows Task manager.

I would have thought it should be the reverse…for instance because of additonal CPU requirements of the OS one would see slightly more CPU in Windows Taskbar compared to Podiums CPU meter but certainly not less. In my case and H-Man it is 50% less!

Podium is still utilising all 4 cores evenly but I am somewhat puzzled as to why Podium’s CPU meter shows 50% and Windows Task Manager…25%.

I just did a quick test with Sonar and it mirrors the Windows task manager almost exactly. With only a very slight difference…2-3 % max, either way.

Also I am fairly certain H-Man is running Windows XP…I am running Vista. So it does not appear to be an OS related issue.

Any ideas Frits?

The percentage shown in the Podium CPU indicator shows the duration of the total processing compared to the max time available before an ASIO buffer overload would occur. Notice that it is the duration and not the actual CPU usage that is indicated. The actual CPU distribution you see in the task manager will depend on serial/parallel routings of the plugins in your the arrangement.

For example, in the screenshot at the start of this topic you have a plugin chain with a Messiah VSTi routed into a Nebula3 Reverb. The Messiah plugin must be processed fully before its output can be processed by Nebula3. In this example it is likely that the first core processes the Messiah VSTi and the second core processes the Nebula reverb, making it appear that the CPU load is lower in the task manager. The CPU load is distributed on the cores, but the plugin on one of the cores needs to wait for the output of the plugin on the other core. The core that is waiting will of course not use any CPU while it waits.

This also means that you will be able to add plugins to other tracks that can be processed in the idle time of the cores without affecting the Podium CPU indicator. You can try this out by setting up an arrangement with a single track that has an effect chain using a substantial amount of CPU. You will be able to add a second track with the exact same chain without affecting the Podium CPU indicator, but the task manager CPU usage will of course double.

I hope this wasn’t too technical.

Thanks for the clarification Frits. However it has raised another question for me…

@Zynewave wrote:

The percentage shown in the Podium CPU indicator shows the duration of the total processing compared to the max time available before an ASIO buffer overload would occur. Notice that it is the duration and not the actual CPU usage that is indicated. The actual CPU distribution you see in the task manager will depend on serial/parallel routings of the plugins in your the arrangement.

This may sound strange but I think what you have just said appears to totally contradict your own description of the CPU Mix indicator in Podium…

“The first percentage shows how much of the available CPU is being used to process plugins and mix audio”. Which surely means…actual CPU usage.

But you just said “not the actual CPU usage”.

Which is it? ❓ ❓ ❓

@Zynewave wrote:

The first percentage shows how much of the available CPU power is being used to process plugins and mix audio

Maybe that is an inaccurate description. How about replacing “power” with “time”:

The first percentage shows how much of the available CPU time is being used to process plugins and mix audio.

❓

For consistency and to avoid confusion definitely yes. That certainly sounds better as it lines up with the existing description that Podium offers in the CPU indicator tool tip. 🙂

However… it appears Podium crucially still does not provide a simple way to see exactly what the actual CPU usage is at any given time.

Why is this so important..?

Actual CPU usage is exactly what other hosts show and is surely what a typical user will think Podium will also offer…but surprisingly it does not….yet.

I think we had a similar discussion about this some time ago.

I suggested a U meter for underuns back then, but based on your recent comments, I would suggest leaving the Mix CPU meter ‘as is’ and adding an actual CPU usage meter to Podium instead.

Or having one meter to show underunns, one for actual CPU usage and still keep the File indicator. But CPU usage for me is easily *the* most important indicator to have. The current indicators are small enough, so another would not IMO get in the way at all.

I would be happy to drop one of the other indicators for an acutal CPU usage indicator if that was the only way to have it in Podium.

In H-man’s and in my own case, having a 50% difference in Podiums reading compared to Windows Task Manager (even if Podium is monitoring the same CPU differently) is as confusing as it is alarming. Needlessly IMO.

If you add an ‘actual CPU usage meter’ then a user can simply look at that and immeadiately see just how much CPU is beng used in a way they are already familiar with.

For a user to have to call up Windows Taskbar to see actual usage means…

a. Podium’s CPU indicator starts spiking.

b. A user has to constantly have Windows task bar open to get some idea of actual CPU usage.

The current Mix / File indicators are clever and useful (no question) but to not have any way to see actual CPU usage at a glance is a massive omission IMO. Definitely needed.

Also with a dual/quad core system it would be great to see each core in Podium. Espcially with the Mix indicator CPU spiking, that takes place with the Task Manager open.

What do you think?

@Zynewave wrote:

Indeed, why is it important? Is it to satisfy your technical curiousity?

Quite the opposite… 🙂 it’s to avoid having to juggle CPU calculations between the mix meter and Windows task manager when one really should be focused on making music. A brief glance to see an actual CPU usage meter is the way 99.9% of software based musicians have been working for years in other hosts. Nothing new here Frits. Really.

I don’t see the point of showing how hard your PC is working when that info by itself is useless

Useless for you. 🙂 Not for me and 99% of Podiums target market. Users of similar hosts. I understand your personal preference Frits. But I see no reason why your personal preference for the way Podiums indcators work cannot still work along side a simple (if need be optional) actual CPU usage indicator as well.

Just so you know…the info you present with the Mix / File indicators is not currently presented in any other hosts I know of (Maybe FL), so I don’t want to lose that but…I still want to have an at a glance look at an actual CPU usage indicator in Podium.

How can I put this…think ‘add’ not ‘replace’.

It is much more important to know how close you are to overloading the processing before clicks and pops will occur.

Very important yes but why can’t we have the best of both worlds in Podium with an actual CPU usage reading which would elevate Podium above any host I know of (for CPU measurement) as that kind of detail ( Mix / File indicators + actual CPU usage) is not yet available anywhere.

Let me give you a worst case example of relying on actual CPU usage:

On a quad-core machine you happen to have set up a chain of four plugins that each consume 25% CPU. An actual CPU usage would show 25% load, but in reality the engine is using 100% of the time allowed by the ASIO driver, causing frequent overloads. On an octo-core machine the worst case scenario would cause overloads at 12.5%, etc.

Interesting example. I would not however and I doubt anyone else would explicitly rely on any CPU meter but try to work (by bouncing or freezing ) well within the readings for any CPU related indicator. But actual CPU usage still remains a useful indicator to have. It mirrors indicators elsehwere and does not need in anyway to ‘replace’ the existing indicators.

Why not have it disabled by default if you really cannot see the need for it. Seriously. As a developer no doubt you too have your own preference for features and the look and feel Podium adopts, nothing wrong with that.

There are other ways than the task manager to monitor the actual CPU usage. In Vista you have the CPU usage gadget in the sidebar. You can download gadgets that display the usage for each core. For XP I think you can find CPU monitoring utilities that e.g. run as a status indicator in the taskbar

.

CPU gadget/s in the Sidebar?

Bad idea.

The more gadgets you have running in the sidebar (as pretty as convenient as it is) the more CPU resources you give away. Also it can attempt to refresh certain gadgets at unexpected times, not something you want during a busy Podium project.

To really get the best out of Vista especially from a developers point of view, less is more. Adding 3rd party apps to monitor CPU usage during serious Music work is really not a good idea at all. Even on a quad. I’ve tested it.

Having said that…
I do understand your point Frits really and do not want to lose the indicators we have but see no reason to not also add a built in indicator to avoid having to use another app to monitor something as simple as actual CPU usage.

A built in indicator would clearly not get in the way of Podium’s performance or the general running of the app. Sidbear gadgets will.

3rd party apps very likely will as well. Bear in mind they are not designed for Music Producers who need as clean a system as possible for music making.

@Zynewave wrote:

Can you tell me exactly for what use you want to know the actual CPU usage?

I have gone into great detail already in this thread as to why I think such a feature would be useful /what I would use it for e.t.c in Podium. I really think we simply have difference of opinon on the matter which is totally cool. 🙂

The fact that it is shown by most other hosts is not reason enough for me.

I gave other reasons but you are the developer so it’s your call. I only brought it up becasue of your response to H -Mans’s post, not to get it fast tracked into Podium 1.97, 2.0 or even 2.5. Just a suggestion I think will help that is all. If you do not see it that way…then you are of course perfecly entitled to disagree…you have a slight advantage as well (the Podium codebase is yours) 🙂

You’ll also find posts on forums for other hosts, where users complain that they experience clicks and overload way before their CPU meter is maxed out.

Interesting comment. I have had clicks pops and dropouts in Podium long before the CPU maxes out as well. With or without graphic card tweaks. So even Podium has had this problem.

But in Podiums case the CPU meter can spike randomly as it also AFAICT measures underuns. Which can cause confusion as one must guess what caused the sudden spike..errant FX, Intstrument, graphics settings, underrun…CPU time/ duration e.t.c ???

I could however skip the guesswork with an additional CPU usage meter.

I don’t see the point of showing that your CPU may only be using 25% of the available power, if you cannot make use of this power due to plugin routings.

But Podium (as demonstrated by H-Man and I) clearly can show 50% more CPU activity than Windows Task manager which is more confusing IMO (even if you cannot use the CPU) than adding a CPU usage meter to better mirror standard CPU host readings.

The current indicator is a general indication of how much you can do in Podium, before reaching the limits of your PCs resources. Ignore the actual CPU usage numbers, and just focus on making music.

The current CPU set up is IMO distracting at times that is why I brought the suggestions for the addition of a more familiar CPU indicator.

There are of course bigger fish to fry in Podium especially as it approaches v.2…timstretching, Rewire, solving automapping issues e.t.c. so really if you add the feature a year from now or never there are far more important features I would like to see first in Podium anyway. 🙂