Previous Thread
Next Thread
Print Thread
Rate This Thread
Hop To
Page 1 of 2 1 2
#2605143 - 10/15/08 01:03 PM please tell me the truth about FSX and multi-processing..  
Joined: Nov 2005
Posts: 1,168
JAS39 Offline
Member
JAS39  Offline
Member

Joined: Nov 2005
Posts: 1,168
NYC
Hi All.

Having read almost all the articles one can find here, as well as on fsinsider, tomshardware (the charts, etc) I get a variety of opinions, most of them contradictory, regarding how much (if any) multi-core CPUs help when running FSX. Microsoft says that after the 2 service packs, FSX should be able to use alot of the extra power of multi-core CPUs. However, other sites claim differently.

Take a scenario: I run a pc designed ONLY for FSX, SP2, Acceleration. What I want to know:

With cost/performance considerations in mind, Is the increased power of a quad-core compared to dual core worth it? Will it increase the performance that much to justify the price?

What about multi-GPU configurations? Why do they perform so badly?

Thanks for any advice.


Apple Macbook Pro Generation 10.1 (Summer 2012)
15", 2880x1800 IPS Samsung Display
2.3 Ghz Intel Core i7-3615QM
8GB DDR3 Memory
1GB Nvidia GT-650M
256GB SSD
Inline advert (2nd and 3rd post)

#2605287 - 10/15/08 04:05 PM Re: please tell me the truth about FSX and multi-processing.. [Re: JAS39]  
Joined: Oct 2006
Posts: 1,801
Heretic Offline
Member
Heretic  Offline
Member

Joined: Oct 2006
Posts: 1,801
GER
As a quad-core (and former dual core) owner, I can say that multi-core CPU's are definately supported by FSX. Even if four cores don't improve your frame rate, they *do* help with terrain and texture loading.
Performance monitors confirm this, by the way. Compared to my dual core, I don't see 100% CPU activity all the time anymore. All four cores are only maxed out during initial loading or when Active Sky X makes changes to the weather or when the engine needs to load a new set of texture tiles.


I would recommend a (45nm) Quad to everyone who can spare the money. Combined with 4GB Ram, they make FSX shine.
You still need to overclock them to get the best performance, but with the current generation of Quads, this shouldn't be much of an issue.


I don't know whether or not you will see a boost coming from a 45nm Duo, but for me, the jump from an old E6600 (at 3.2Ghz) and 2GB Ram to a Q9450 (at 3.2Ghz) and 4Gb Ram was *very* noticable.



As for multi-GPU configurations please consider that FSX's engine is essentially eight years old (FS2000). Back then, SLI and Crossfire were not "in" anymore (SLI) or not even thought of (CF) respectively. While it was easier to add things like bloom and more terrain details, implementation of SLI was either too difficult or time-consuming or ACES decided to miss out on it because it appeared to them as a temporary trend only.
If you want to get the max out of FSX, get a single, powerful GPU card like an 8800GTX (yes, it's still recommended due to the 384bit memory interface) or 280GTX. Even an old G80 8800GTS will do the trick nicely (312 bit memory interface).


Personally, I wouldn't give a damn about what teams like Tom's Hardware & Co say about FSX. There is enough information about dual core vs quad core out there in the flightsim forums written by people who mainly, if not only focus their spare time on FSX and thus have way more insight into the whole subject than the "let's do quick FSX benchmark before we move on and test GPUs in CoD4" guys.

The hardware section in the forums at Avsim is a good place to ask for any technical advice, although I don't recommend opening a "Duo vs Quad" thread in there, since this topic is as much a dead horse to the community as the evergoing "Boeing vs Airbus" discussion. I suggest doing a forum search and reading through the threads a bit if you need a bit of help with the decision.


Summary:
- FSX likes Mhz most, so squeeze the most out of your CPU
- Quads help with texture loading
- 4GB are recommmended
- Multi-GPUS are not supported due to the engine's age

#2605533 - 10/15/08 09:30 PM Re: please tell me the truth about FSX and multi-processing.. [Re: Heretic]  
Joined: Feb 2000
Posts: 3,904
Tolwyn Offline
Senior Member
Tolwyn  Offline
Senior Member

Joined: Feb 2000
Posts: 3,904
WA, United States
There's a huge difference between processor affinity and multi-threaded.
FSX is not a multi-threaded application.

?


My personal licensing agreement: In exchange for my hard-earned cash for your product, you agree to the following terms: No part of my hardware may be used as a mechanism to verify or reverify my economical patronage. My receipt will serve that purpose. If you disagree with this license, you may return my money to me, and I'll return your product. \:\)
#2605824 - 10/16/08 06:31 AM Re: please tell me the truth about FSX and multi-processing.. [Re: Tolwyn]  
Joined: Aug 2005
Posts: 145
Xptical Offline
Member
Xptical  Offline
Member

Joined: Aug 2005
Posts: 145
Macon, GA, USA
The best bet with any *normal* user is to get the fastest processor you can afford. Then look at cores.

If a 4ghz single core and a 3.8ghz dual core are the same price, the 4ghz single core will perform better. Likewise, if you have a 3.8 dual or a 3.6 quad, the 3.8 dual will outperform.

Now, FSX may utilize dual cores for background tasks. But the main code for the game will still operate on a single thread inside a single core. And the faster that core is, the better.


[img]http://www.speedtest.net/result/649739859.png[/img]
#2606570 - 10/28/08 03:01 AM Re: please tell me the truth about FSX and multi-processing.. [Re: Xptical]  
Joined: Nov 2003
Posts: 121
tcable Offline
Member
tcable  Offline
Member

Joined: Nov 2003
Posts: 121
Taunton, MA, USA
I'm running a slightly overclocked Q6600 Vista x64 and 4gb ram.

I love FSX now. I'm mostly maxed on all sliders and performance is amazing even in New York.

With PMDG, I'm in sim heaven (until FS11 arrives in 2010 or so)

I highly encourage the Quad, but agree that raw speed is king.

#2608168 - 10/30/08 04:05 PM Re: please tell me the truth about FSX and multi-processing.. [Re: tcable]  
Joined: Oct 2006
Posts: 1,801
Heretic Offline
Member
Heretic  Offline
Member

Joined: Oct 2006
Posts: 1,801
GER
Take a fast quad and you're in FSX heaven.

FSX supports basic multi-coring, it simply uses it for loading purposes.

#2609586 - 11/02/08 01:00 PM Re: please tell me the truth about FSX and multi-processing.. [Re: Heretic]  
Joined: Nov 2005
Posts: 1,168
JAS39 Offline
Member
JAS39  Offline
Member

Joined: Nov 2005
Posts: 1,168
NYC
ahh...thanks for all the info! more money=buy a quad and overclock!


Apple Macbook Pro Generation 10.1 (Summer 2012)
15", 2880x1800 IPS Samsung Display
2.3 Ghz Intel Core i7-3615QM
8GB DDR3 Memory
1GB Nvidia GT-650M
256GB SSD
#2610391 - 11/03/08 10:55 PM Re: please tell me the truth about FSX and multi-processing.. [Re: Tolwyn]  
Joined: Feb 2002
Posts: 2,918
Rilex Offline
Senior Member
Rilex  Offline
Senior Member

Joined: Feb 2002
Posts: 2,918
Washington
Originally Posted By: Tolwyn
There's a huge difference between processor affinity and multi-threaded.
FSX is not a multi-threaded application.

?


If FSX wasn't multithreaded, how do you propose getting a single process on multiple cores/CPUs?

Hint: It isn't possible. FSX is multithreaded.

#2610877 - 11/04/08 09:14 PM Re: please tell me the truth about FSX and multi-processing.. [Re: JAS39]  
Joined: Oct 2006
Posts: 1,801
Heretic Offline
Member
Heretic  Offline
Member

Joined: Oct 2006
Posts: 1,801
GER
Originally Posted By: JAS39
ahh...thanks for all the info! more money=buy a quad and overclock!


Don't forget a new cooler if you overclock your quad.


Most coolers from dual-core days can't cope with four hot cores.

#2610920 - 11/04/08 10:31 PM Re: please tell me the truth about FSX and multi-processing.. [Re: Heretic]  
Joined: Feb 2000
Posts: 3,904
Tolwyn Offline
Senior Member
Tolwyn  Offline
Senior Member

Joined: Feb 2000
Posts: 3,904
WA, United States
Uh, FSX is not a mutli-threaded application. Sorry, man.


My personal licensing agreement: In exchange for my hard-earned cash for your product, you agree to the following terms: No part of my hardware may be used as a mechanism to verify or reverify my economical patronage. My receipt will serve that purpose. If you disagree with this license, you may return my money to me, and I'll return your product. \:\)
#2610947 - 11/04/08 11:36 PM Re: please tell me the truth about FSX and multi-processing.. [Re: Tolwyn]  
Joined: Feb 2002
Posts: 2,918
Rilex Offline
Senior Member
Rilex  Offline
Senior Member

Joined: Feb 2002
Posts: 2,918
Washington
FSX is a multithreaded application. You have to have more than one thread in order to run a single process on more than one proc/core. Unless you want to tell the Windows Kernel Engineers how Windows runs a process over more than one proc/core.

#2610955 - 11/04/08 11:56 PM Re: please tell me the truth about FSX and multi-processing.. [Re: Rilex]  
Joined: Feb 2000
Posts: 3,904
Tolwyn Offline
Senior Member
Tolwyn  Offline
Senior Member

Joined: Feb 2000
Posts: 3,904
WA, United States
You guys don't know what multi-threaded means, apparently.

You can set process affinity, that doesn't mean multi-threaded.

Quote:

Multi-threading refers to an application with multiple threads running within a process, while multi-processing refers to an application organised across multiple OS-level processes.


Sigh.


My personal licensing agreement: In exchange for my hard-earned cash for your product, you agree to the following terms: No part of my hardware may be used as a mechanism to verify or reverify my economical patronage. My receipt will serve that purpose. If you disagree with this license, you may return my money to me, and I'll return your product. \:\)
#2610965 - 11/05/08 12:18 AM Re: please tell me the truth about FSX and multi-processing.. [Re: Tolwyn]  
Joined: Feb 2002
Posts: 2,918
Rilex Offline
Senior Member
Rilex  Offline
Senior Member

Joined: Feb 2002
Posts: 2,918
Washington
You're misreading that.

A multithreaded application consists of a single process that has multiple threads, e.g. fsx.exe. This allows the process' threads to be spread across (have its proess affinity) multiple processors (or cores as it may be).

Process affinity assigns which processors or cores the processes threads can run on. If you set the process to only have access to a single processor/core, it will still be a multithreaded application, but only able to execute one thread at a time. If the process had a single thread, while it may be assigned to multiple processors or cores, it can only execute that single thread (think: "Hello World!") on a single processor/core.

Since FSX is a multithreaded application, and processes in Windows are started with the process affinity set to all available processors/cores, the OS can execute n of FSX's threads at once, depending on processor availibility, current workload, and what work FSX needs to be done.

A multiprocess application is an application that consists of multiple processes. This is typically for clustering scenarios (render farms and the like).

You need to go read Windows Internals. You're not understanding the fundamentals of process scheduling and threading.

You can also argue til you're blue in the face with Phil Taylor, if you'd like. He'll shoot you down, just like we are.

#2611112 - 11/05/08 04:53 AM Re: please tell me the truth about FSX and multi-processing.. [Re: Rilex]  
Joined: Nov 2005
Posts: 1,168
JAS39 Offline
Member
JAS39  Offline
Member

Joined: Nov 2005
Posts: 1,168
NYC
sorry for asking, but who is Phil Taylor?


Apple Macbook Pro Generation 10.1 (Summer 2012)
15", 2880x1800 IPS Samsung Display
2.3 Ghz Intel Core i7-3615QM
8GB DDR3 Memory
1GB Nvidia GT-650M
256GB SSD
#2611142 - 11/05/08 06:35 AM Re: please tell me the truth about FSX and multi-processing.. [Re: JAS39]  
Joined: Feb 2002
Posts: 2,918
Rilex Offline
Senior Member
Rilex  Offline
Senior Member

Joined: Feb 2002
Posts: 2,918
Washington

#2611270 - 11/05/08 02:05 PM Re: please tell me the truth about FSX and multi-processing.. [Re: Rilex]  
Joined: Nov 2005
Posts: 1,168
JAS39 Offline
Member
JAS39  Offline
Member

Joined: Nov 2005
Posts: 1,168
NYC
thanks, rilex. Anyway, at least, FSX for now increases the loading times trememdously, which can only be good! I hope that FS 11 will really provide increased performance for multi cores and mulit gpu setups...


Apple Macbook Pro Generation 10.1 (Summer 2012)
15", 2880x1800 IPS Samsung Display
2.3 Ghz Intel Core i7-3615QM
8GB DDR3 Memory
1GB Nvidia GT-650M
256GB SSD
#2611438 - 11/05/08 05:56 PM Re: please tell me the truth about FSX and multi-processing.. [Re: JAS39]  
Joined: Feb 2002
Posts: 2,918
Rilex Offline
Senior Member
Rilex  Offline
Senior Member

Joined: Feb 2002
Posts: 2,918
Washington
Right, the RTM version (and possibly SP1) was more optmized wrt multithreading when it came to loading, and less so in other areas. That improved with SP2.

But, it should be obvious to anyone that since there is an 8 core fix for FSX, the application is multithreaded.

Remember boys and girls, processes are not executed, threads are. A thread cannot be on more than one core at any one time (the OS can move the thread from core to core, but it only ever executes on one core at any one time).

#2611611 - 11/05/08 10:33 PM Re: please tell me the truth about FSX and multi-processing.. [Re: Rilex]  
Joined: Feb 2000
Posts: 3,904
Tolwyn Offline
Senior Member
Tolwyn  Offline
Senior Member

Joined: Feb 2000
Posts: 3,904
WA, United States
Nope.
Nope.
Nope.

FSX is not fully multi-threaded. Sorry. Precache/loading of texture does not a multi-threaded application make. Man. It's like I'm arguing with democrats here.

Bring that guy here and have him prove me wrong. smile Utilizing a full multi-threaded app is more than just caching textures. From tdragger's own blog:

Quote:
The bad news is that requests are made with varying frequency so the overall CPU utilization will also vary. In other words, those of you running [...] FSX [...] and looking for 100% utilization on all your cores can just stop--you're not going to see it. You'll see a lot of utilization when you first load a flight (and we force requests to complete) and less as you fly along. As we continue to evolve the code base we'll continue to look for areas where thread offloading makes sense but changes in the area can have unexpected results so it will take time to decide what works best. And, oh, when you find a game that does use all that horsepower all the time, please let me know.


This is thread affinity, not mutli-thread utilization.

Last edited by Tolwyn; 11/05/08 10:39 PM.

My personal licensing agreement: In exchange for my hard-earned cash for your product, you agree to the following terms: No part of my hardware may be used as a mechanism to verify or reverify my economical patronage. My receipt will serve that purpose. If you disagree with this license, you may return my money to me, and I'll return your product. \:\)
#2611636 - 11/05/08 11:19 PM Re: please tell me the truth about FSX and multi-processing.. [Re: Tolwyn]  
Joined: Feb 2002
Posts: 2,918
Rilex Offline
Senior Member
Rilex  Offline
Senior Member

Joined: Feb 2002
Posts: 2,918
Washington
You do not understand the term "multithreaded". Multithreaded means more than 1 thread. "Hello World!" is not multithreaded. FSX is multithreaded. It can, and does, execute more than one thread at a time on a multicore system.

And..

"FSX is not fully multi-threaded." != "FSX is not a mutli-threaded application."

Which is it? You've contradicted yourself.

Quote:

This is thread affinity, not mutli-thread utilization.


A thread does not have affinity. A thread cannot execute on more than one processor/core at a single time. A process has affinity. You may be confused with MSDN documentation that would elude to thread affinity, but SetThreadAffinityMask only allows you to set what processor that particular thread runs on, not set the thread to run on multiple processors/cores (which again, is not possible).

Please don't argue this point, you've already lost by contradicting yourself. You're not grasping the terminology nor what it means to have a multithreaded application.

Quote:

loading of texture does not a multi-threaded application make.


Actually, it does. Even if the multithreading takes place in limited areas of the application, or if the application is only optimized for multithreading in limited areas, it is still a multithreaded application.

Sorry, not to be mean here, but you really need to read Windows Internals. You've confused yourself, and I'm afraid you're confusing others who are reading your posts.

And, you should quote farther down on his blog post ... http://blogs.msdn.com/tdragger/archive/2006/08/21/711152.aspx

Quote:

Hopefully you can see that a multithreaded game like FSX consists of a numerous start, wait, and complete sequences.


Hopefully this ends the argument as to FSX not being multithreaded. Unless you'd like to continue to tell the ACES team that what they publically post is incorrect, Towyln.

#2611673 - 11/06/08 12:45 AM Re: please tell me the truth about FSX and multi-processing.. [Re: Rilex]  
Joined: Feb 2000
Posts: 3,904
Tolwyn Offline
Senior Member
Tolwyn  Offline
Senior Member

Joined: Feb 2000
Posts: 3,904
WA, United States
I stand by my post without question. FSX is not a multi-threaded application.
And I challenge the Aces team to prove, fully, that it is... when they themselves have only said "at run time, we'll take one core to load textures, and another core to "load other things". That is great, if you edit the *.ini and tell the software which core to use for which task.

smile I'm fine with my stance. I stand by it.


My personal licensing agreement: In exchange for my hard-earned cash for your product, you agree to the following terms: No part of my hardware may be used as a mechanism to verify or reverify my economical patronage. My receipt will serve that purpose. If you disagree with this license, you may return my money to me, and I'll return your product. \:\)
Page 1 of 2 1 2

Moderated by  RacerGT 

Quick Search
Recent Articles
Support SimHQ

If you shop on Amazon use this Amazon link to support SimHQ
.
Social


Recent Topics
Carnival Cruise Ship Fire....... Again
by F4UDash4. 03/26/24 05:58 PM
Baltimore Bridge Collapse
by F4UDash4. 03/26/24 05:51 PM
The Oldest WWII Veterans
by F4UDash4. 03/24/24 09:21 PM
They got fired after this.
by Wigean. 03/20/24 08:19 PM
Grown ups joke time
by NoFlyBoy. 03/18/24 10:34 PM
Anyone Heard from Nimits?
by F4UDash4. 03/18/24 10:01 PM
RIP Gemini/Apollo astronaut Tom Stafford
by semmern. 03/18/24 02:14 PM
10 years after 3/8/2014
by NoFlyBoy. 03/17/24 10:25 AM
Copyright 1997-2016, SimHQ Inc. All Rights Reserved.

Powered by UBB.threads™ PHP Forum Software 7.6.0