1 hour ago, JoeFackel said:

PL and P3D is a no-no, thats what the AM-Setting in the prepar3d.cfg is therefore.

Here I have P3D with it’s own AM value , the addons starting with their own affinity settings through a batchfile and all other processes by PL.

No HT.

Edited December 14, 20187 yr by GSalden

I have never, not once... seriously, never had a valid reason to turn off hyperthreading.  If you want to reduce CPU heat... liquid cooling is the better choice, not ripping out 50% of your CPU's capability.

I look for quick and easy solutions, I dont want to have to use BAT files to set AM, this is why I tried LP,  I just want to plug my Laptop in and fly, Lasso has enabled me to do that and get a stable stutter free performance at a good level of visuals.

I think that HT on or off isnt as important as making sure that P3d is maximizing your hardware's capabilities, AM whether set in the CFG or using a tool like Lasso is key to this. I would look here first before looking at HT.

15 minutes ago, WarpD said:

I have never, not once... seriously, never had a valid reason to turn off hyperthreading.  If you want to reduce CPU heat... liquid cooling is the better choice, not ripping out 50% of your CPU's capability.

 

Could you please elaborate how specifically P3D 4.4 benefits from HT=on? I'm aware that other modern software use HT extensively, but I have never heard anything similar related to P3D.

1 hour ago, G-YMML1 said:

 

Could you please elaborate how specifically P3D 4.4 benefits from HT=on? I'm aware that other modern software use HT extensively, but I have never heard anything similar related to P3D.

Dude, there are at least 10,000 posts with probably a million views on the subject ‘HT - to be or not to be’ here at Avsim alone.

not speaking for Warp but rather to what he posted. He clearly states that p3d has given him no reason not to use HT. It’s clearly not a HT on vs HT off statement.

 

 

Edited December 14, 20187 yr by FunknNasty
Associate Warp’s ht preference to p3d

Posts from 5 or 10 years ago are not anymore relevant.

I run P3D on a 9900K.
With HT: stutters.
Without HT: smooth.

Simply as that.

5 minutes ago, FunknNasty said:

He clearly states that p3d has given no reason not to use HT

In fact LM has come out on HT, while not suggesting it is a problem they do recommend HT off to avoid problems that can occur when core 0 is logically split due to how P3D itself wants to load core0.  My interpretation is that the goal is to have as much core 0 running as available.

5 minutes ago, downscc said:

In fact LM has come out on HT, while not suggesting it is a problem they do recommend HT off to avoid problems that can occur when core 0 is logically split due to how P3D itself wants to load core0.  My interpretation is that the goal is to have as much core 0 running as available.

^

This.

Although I agree with the theory that HT either on or off makes very little difference in P3d4. It's a matter of personal preference, since everyone's hardware and software is different.

 

13 minutes ago, downscc said:

In fact LM has come out on HT, while not suggesting it is a problem they do recommend HT off to avoid problems that can occur when core 0 is logically split due to how P3D itself wants to load core0.  My interpretation is that the goal is to have as much core 0 running as available.

Yeah, dan my bad ...it was my intent to phrase my post as Warp not having a reason not to use HT with p3d. 

1 hour ago, Langyboy63 said:

I look for quick and easy solutions, I dont want to have to use BAT files to set AM, this is why I tried LP,  I just want to plug my Laptop in and fly, Lasso has enabled me to do that and get a stable stutter free performance at a good level of visuals.

I think that HT on or off isnt as important as making sure that P3d is maximizing your hardware's capabilities, AM whether set in the CFG or using a tool like Lasso is key to this. I would look here first before looking at HT.

Batchfiles start apps on specific cores, while PL pushes them towards certain cores when they are already running...

That is a big difference ...

Therefore we also do not use PL icw P3D but use a direct AM..

SteveW has explained this several times. Just use Search ...

Edited December 14, 20187 yr by GSalden

For all you Ryzen and Threadripper guys out there...

On my current TR 2990WX I have seen virtually no difference between SMT (HT on AMD) On or Off in P3D. Maybe slightly less pauses in Heavy Duty scenery areas with SMT off but this might be a placebo.

Personally I keep SMT off to keep the workload from being spread over too much but also since I OC it less power draw OCing to 4.1GHZ with SMT off as well.

Works well. Ryzen 7 and lesser core TR's SMT off way to go as well. Ryzen 5s I'd leave SMT on to not bog down the cores as there are far less cores on the 5s.

Biggest thing though is due to the nature of AMD's Infinity Fabric is ensuring an adequate RAM speed. Sweet spot is around 3200mhz with tight timings. Higher speed at higher latency is virtually a wash on the Ryzen/TR's above 3200. Unless you can manage 3466/3600 at CL15/CL16 then it is worth it. But the latter is very hard to achieve on the x399 chipset.

For you Intel i7/i9 7th to 9th K series guys (vast majority of users) seems like the consensus is definitely HT Off for the most part. I wonder if any of you that are running 18+ Core Extreme Edition chips. You may have a similar experience to me that HT On/Off there is basically no difference.

2 hours ago, WarpD said:

I have never, not once... seriously, never had a valid reason to turn off hyperthreading

I was getting the "blurries" with MSE and turned off HT and the scenery is now crisp and clear.  Have a feeling it is related to my i7 8086K CPU with all cores overclocked to 5.0GHz.  If I can find a way to get rid of the blurries (even though my setting are not all maxed out), then I will turn it off.  I really do not think HT is required for modern CPU's.  At least that is some of the reading I have seen on the Internet.  It is old tech.

That is a great chip Jim! Lucky you!

I'm surprised you had issues with that. The high ipc of that chip and really all the i7 Intel K series' are so well optimized for P3D.

2 hours ago, G-YMML1 said:

Folks, 

Thanks for your comments, but i think you hijacked the topic into different direction a bit 🙂 My only concern is whether P3D4.4 will suffer or not without HT. If it will suffer, then I simply dial the OC back to 4.8 and turn HT on. Honestly, I don't wanna do that as the whole idea behind 9900k purchase was to have it on 5.0 stable OC. 

AM edits, PL...all of these stuff is so 2015/2016 🙂

Depends on how many cores your CPU has..

For a quad, HT makes sense, coupled with

AffinityMask=253
// 253=11 11 11 01

For a hex processor, HT off should give you enough cores to run P3D + addons.

1 hour ago, Jim Young said:

I really do not think HT is required for modern CPU's.  At least that is some of the reading I have seen on the Internet.  It is old tech.

SMT in and of itself isn't "old tech". While it's been around for a few years (since the P4 in the x86 world) it's become increasingly necessary as CPUs got faster and faster and cache/memory (never mind I/O) didn't keep pace. The premise of HT was that if your core was stalled for several thousand cycles waiting on L2 or L3 cache or (gasp) RAM, you could have the execution units do something else while that thread was stalled.

The challenge with SMT is that it's a security risk - with speculative execution and timing attacks, you don't want to have other processes (or users) executing on and changing the state of your core. That's what Spectre and Meltdown were all about. In our worlds, they don't matter much, but then again to Intel and AMD, we don't matter much compared to the Amazons, Googles and Microsofts of the world who buy very, very large processors to be used in a multi-tenant world.

Given the security risks and almost unlimited transistor budgets, it makes more sense just to have more real cores and to take a pass on SMT. Just like in the Intel world, where it appeared in the P4, then disappeared until Sandy Bridge, I expect SMT may make a comeback if at some point we either work around the security implications or start getting limited transistor budgets again.

Cheers!

Luke