Windows 10: New member with an x64 prefetch issue (I think)...

Greetings, all,

Just joined the board because I have a strange problem with my new laptop with Windows 10 Home x64 (latest non-Anniversary version) that is driving me nuts.

Specifically, the problem is that the OS is not creating an NTOSBOOT.pf file in the prefetch folder. Instead, at each boot it creates or updates an individual .pf for EVERY file involved in the boot process, instead of consolidating the information in these individual files into the single NTOSBOOT.pf and suppressing the individual ones. As a result, the boot process is never optimized, and defragmenting the disk never gets the boot files placed in optimal locations for speed. The machine, not surprisingly, boots very slowly, but all other applications load very quickly. This has been going on for the 1 week I have owned the machine and through at least 20 reboots (both warm and cold).

I have looked at the registry key
HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\PrefetchParameters

where I see both EnablePrefetcher and EnableSuperfetch, and both are set to a DWORD value of 3, so that doesn't seem to be the problem.

Did MS, in its infinite wisdom, change the way prefetch handles booting up, or is something else going on? Any ideas would be greatly appreciated!

Regards,


:)

 

Windows 10 Creators Update slow boot - Prefetch stopped working?

I think Windows only loads the data in .pf (prefetch) files when you launch the associated application and does not load them at boot (maybe unless the program is on startup). Prefetch works as a sort of cache, that is when you open an application, Windows
checks the Prefetch folder, looks at the application’s .pf file (if it exists), and uses that as a guide to start preloading data that the application will use.

Three minutes is awfully long boot time though, have you tried performing a clean boot? Use
msconfig to disable non-Microsoft services and startup programs. A startup program or service can be one of the offenders (for example, I think Chrome also prefetches data).

Try also if you can reproduce the issue when starting in Safe mode. But yeah, the usual suspects for this issue are the Windows Search, Prefetch, Storage Spaces and BITS services.

 

C:\Windows\Prefetch is corrupt and unreadable

How do you know your prefetch folder is corrupt?

To fix this issue, simply delete the contents of the Prefetch folder . . .

Note: your first few boots may me a bit slow until Windows rebuilds the Prefetch file systm

 

Why don't I have any of that ?

 

As a further update to this pain in the neck, I notice that in the \prefetch folder there is a file called PfPre_3fc67256.mkd (that I cannot delete unless the Windows Audio Endpoint Builder service is stopped before deleting). This file, once deleted, will get recreated with the same name and extension on the next reboot. It seems to be a precursor to the never-created ntosboot.pf file.

Also, in the \prefetch\readyboot folder, in addition to the trace*.fx file created on every boot, there is also a file called rblayout.xin (that extension is correctly spelled) which gets created with the same date and time stamp as the newest trace* file.

Something is really out of whack here. I'll try another clean install, but that didn't work the first time so I'm not holding out any great hope of a fix.

 

That looks like something like a problem with some drivers, it just got stuck in prefetch because it's indexing it.

 

Thanks, CountMike, for the replies.

Sorry for the long delay in getting back to this. Had a sudden, unexpected surgery that has taken a lot longer to recover from than I hoped it would. (Pain medication hasn't helped getting back up to speed, either!)

The missing ntosboot.pf problem continues. Another fresh reinstall produces the problem even before any other software (other than manufacturer-supplied drivers) is installed. Booting up produces 31 different .pf files involved in the process, only 7 of which are related to hardware drivers/system software installed from the HP-provided Windows installer disk. It takes about 60 to 75 seconds for the desktop to appear, but another 1 to almost 2 minutes for disk activity to slow down enough that mouse clicks produce a normal (not significantly slow) response.

I have turned off indexing (and disabled associated service) with no difference. I have turned Secure Boot off and on and off again in the BIOS -- same result. There are no errors or warnings in Event Viewer that refer to any problem in the boot sequence. I even had HP tech support take a crack at it, and they did only the minimal disk cleanup types of things. More free space on the hard drive now, but stilll no ntosboot.pf.

If I had to guess, I would suspect a Windows file system or registry permissions problem that is preventing the boot tracing process from completing. But that seems unlikely, given that prefetch file creation works perfectly for everything else once the OS is fully loaded.

I'm at a total loss. Any other suggestions will be gratefully received.

 

Sorry to hear about your health problem, hope all's well now.
Still think that W10 problem is HP (maybe even particular model) and it's drivers related. Drivers and maybe some brand related programs are just about only thing that distinguishes it from the rest. Parts manufacturers submit drivers to MS for inclusion in Windows so even if you didn't download and install drivers from HP, it is still in the OS anyway. Otherwise everybody would have same features.