A weird P3d performance ANALOGY!

[lownslo 592]

I have for years kept backups of all the sim's ini files.  Just checked the most recent backup for the Prepar3d.cfg dated 11April2022... it is 23.4KB.  Compared to the Prepar3d.cfg from my last flight (yesterday 22June2022) which is 22KB.  Nothing else has changed, no new addons, no tweaks, etc.  Seems my system can debloat itself!!😁

I concur on the importance of donating blood... been doing it since the mid 80's.👍

[SteveW 1,792]

When we first run P3D, or after removing the cfg file, the sim generates the file fresh. The fresh file contains settings pertaining to the system installed on, but some values are not yet included because they equate to default values. The sim reads the file and if a value isn't in there it assumes the default value, that value will appear in the file when the user changes the setting from default, hence the file grows a little by two or three KBytes. Even so, this file is read in once at the startup of the sim and amounts to the same amount of work. There is no change to how the sim performs unless settings were made that require more work, adding traffic or increasing shadows for example. So the only reason that a new cfg might improve performance is because the defaults are back.

Remember that (with all versions of P3D and FSX) when we have Hyperthreading or SMT enabled in the CPU we need to apply an optimised affinity mask to guard against the sim putting scenery loading or other threads on the main thread core since performance is lost that way because the main core is doing more work unnecessarily.

[Luke 782]

14 hours ago, coastaldriver said:

The cfg file gets bigger and bigger over time (it bloats by about 20%) even though i make no changes to the settings I use ... A comparison shows no specific changes to configuration

Then you haven't done a comprehensive diff. The INI file is just a text file full of key/value pairs. It doesn't grow invisibly.

[KL Oo 695]

Well, to be honest....no. the CFG file is pretty much that...a file that's holding configuration settings. If deleting it and starring again has effected performance then I'd suggest it was a setting that was slowing things down....not 'bloat'.

[spilok 1,132]

1 hour ago, KL Oo said:

Well, to be honest....no. the CFG file is pretty much that...a file that's holding configuration settings. If deleting it and starring again has effected performance then I'd suggest it was a setting that was slowing things down....not 'bloat'.

It's curious though, because many on this forum recommend deleting the old cfg and starting a new one.  I've read that many, many times, and in my opinion, it's not a placebo, but a technique that seems to work for me.  You should do what works for you, but I will continue to believe that a new cfg makes my sim fly better, smoother, and more efficiently.  It's your call.

Stan

[Luke 782]

17 minutes ago, spilok said:

You should do what works for you, but I will continue to believe that a new cfg makes my sim fly better, smoother, and more efficiently.  It's your call.

In the absence of data and determining what has actually changed in the config file, it's about as effective as saying three Hail Marys before starting the sim to avoiding a CTD. Although I've heard on the forums that only works for Catholics.

Cheers!

[spilok 1,132]

16 hours ago, Luke said:

In the absence of data and determining what has actually changed in the config file, it's about as effective as saying three Hail Marys before starting the sim to avoiding a CTD. Although I've heard on the forums that only works for Catholics.

Cheers!

I'll try that!

[Multisim 116]

This must be one of the weirdest threads ever. You talk of the config file like it's some kind of self-aware magical creature that has developed artificial intelligence and grows and adds FPS limiting magic to itself.

Dudes, I hate to break it to you, but it's not magic. It's a plain old text file. It contains a few configuration directives. If rebuilding it has a positive impact on your system, it means you did something that made it end up there. It's not magic, it's a text file. Simply compare the before and after file and fix whatever is broken.

[Rogen 1,087]

2 hours ago, Multisim said:

It's not magic, it's a text file.

Heh... but it does come with a little black magic.

If you use a config profile P3D makes a sort of copy of the main P3D config and places it into ~\Documents\Prepar3D v4 Files

The copy is a partial config file based off a "default" P3D config.

What this means, is if you've extensively tuned your P3D config, your tuning won't be applied to the profile config and you'd need to manually update the file to put your tuning in place.

However if you then modify the profile via the P3D UI you again loose any custom tuning.

The trick is to never edit a config profile via the UI, instead use a text editor like notepad++

Something I learned when P3D seemed to be doing it's own magical thing.

Cheers