W7 Prefetch does not seem to be working.

[johnhc]

I have W7 Ultimate x64 installed on my HW via an unattended install with a number of tweaks, I looked at the Prefetch folder and saw no .pf files and no layout.ini file. I looked at my tweaks and saw that I had not copied my XP Registry tweaks over properly. I tried to correct the Registry but Prefetch did not start working. I then did a un-tweaked install on a VM under VMware Player. Looking shortly after the install, there were many .pf files and a large layout.ini file (about 730 kB). Later when I looked, there were no .pf files but the layout.ini file was still there but unchanged. After four more days and many starts and restarts, there remains no .pf files and the layout.ini file remains unchanged. Please let me know what is going on and/or what I need to do to get the Prefetch function working. Thanks, John.

[MagicAndre1981]

Which settings have you applied?

Is the EnablePrefetcher value set to 3?

[johnhc]

Which settings have you applied?

Is the EnablePrefetcher value set to 3?

MagicAndre1981, thanks for your reply. EnablePrefetcher and EnableSuperfetch are both set to 3. BootFilesOptimized is set to 1 and LayoutFilePath points to my Prefetch folder. All of the settings are default because I have not intentionally modified any of them. Thanks, John.

[johnhc]

OK, I have chased down the problem with Prefetch. The SuperFetch (Sysmain) service was set to Manual and Stopped. I set it to Automatic and started it and Prefetch is working. I used the command Rundll32.exe advapi32.dll,ProcessIdleTasks to create a layout.ini file and to update it. I do not know what stopped SuperFetch but it is not I. In fact, prefetch is working when I first install my system (on VM or HW) then stops working. Here is a good MSFN thread on this subject and the root of my discovery - thanks much to MagicAndre1981. If anyone has an idea on why SuperFetch service is stopped, please let me know. Enjoy, John.

[MagicAndre1981]

the superfetch service is stopped when the WEI detects a fast Disk (SSD). Some users had this with Parallels Desktop under MacOSX. The WEI score had a 6.0 for the HDD and so superfetch was disabled.

[johnhc]

the superfetch service is stopped when the WEI detects a fast Disk (SSD). Some users had this with Parallels Desktop under MacOSX. The WEI score had a 6.0 for the HDD and so superfetch was disabled.

MagicAndre1981, thanks again. I do not have an SDD but I do have a 4x VelociRaptor RAID5 and my HDD score is 6.6. Perhaps this is my problem. Is there a way to defeat the turning off of SuperFetch or is it even necessary? Thanks, John.

[MagicAndre1981]

ok, so you have the cause. The WEI Score is too high. Do you see an improvement when Superfetch is on?

[johnhc]

ok, so you have the cause. The WEI Score is too high. Do you see an improvement when Superfetch is on?

MagicAndre1981, it is hard to tell. I have run no comparisons. I use MyDefrag and it uses layout.ini to optimize the disk layout. I started this quest when I saw that I did not have one. With a little Google, I found the xml files with the WEI scores in "F:\Windows\Performance\WinSAT\DataStore" but cannot find any limit. Thanks, John.

[MagicAndre1981]

can you upload the XML from the WI test?

And, use the integrated defrag tool and not 3rd party tools. Follow my guide, this starts the internal defrag tool which places the files based on the layout.ini and aslo trains the prefetcher too boot faster.

[johnhc]

can you upload the XML from the WI test?

And, use the integrated defrag tool and not 3rd party tools. Follow my guide, this starts the internal defrag tool which places the files based on the layout.ini and aslo trains the prefetcher too boot faster.

MagicAndre1981, thanks. I have read your guide, referenced it in my first reply today, and will consider it. I am also thinking of posting on the MyDefrag forum and see what they say. I have used it for a while on XP x64 and have been very happy with it. I attach a screen shot of the WinSAT folder and will attach your requested file if you will point out which it is, or where it is if not here. Thanks, John.

[MagicAndre1981]

upload the disk XML

[johnhc]

MagicAndre1981, attached. Thanks, John.

[MagicAndre1981]

- <DiskMetrics>
  <AvgThroughput kind="Sequential Read" units="MB/s" ioSize="65536" score="7.6">282.98062</AvgThroughput> 
  <AvgThroughput kind="Random Read" units="MB/s" ioSize="16384" score="5.5">12.74000</AvgThroughput> 
  <Responsiveness Kind="AverageIORate" units="ms/IO" score="7.9" factor="0.0">1.06000</Responsiveness> 
  <Responsiveness Kind="GroupedIOs" units="units" score="7.1" factor="0.0">10.61476</Responsiveness> 
  <Responsiveness Kind="LongIOs" units="units" score="7.8" factor="0.0">3.79089</Responsiveness> 
  <Responsiveness Kind="Overall" units="units" score="7.2" factor="0.0">40.23938</Responsiveness> 
  </DiskMetrics>

The Random Read and AverageIORate are very good. So my guess is, that Windows 7 decided, Superfetch is not needed.

[johnhc]

MagicAndre1981, thanks. I am curious how you got the xml formated. When I Edit it or open it in IE9, the text is strewn out across the screen. I did some searching on the MyDefrag forum and found this tutorial and am curious to know your opinion. Thanks, John.

[MagicAndre1981]

I don't like the guide. The criticism of TheAnonymous are correct.

You can try both guides (my and his) and make 2 boot traces (), generate the XML files and compare the results.