Boost Windows 7 SP1 USB Storage Devices Performance by Increasing Maxi

arkhi · 14 Aug 2011

@Airbot

There was a mention of a requirement to create a registry key even though people siad "There wasn't". That's the point. Oh, and also the point that MS said that VVVV and PPPP are variables, not an actually key itself.

Teerex · 14 Aug 2011

Guys, guuys, this is probably something that will make sense only with USB 3.0, and the vendors will enable it by setting the registry keys with their inf files.

bagavan · 14 Aug 2011

Is it necessary to manipulate the registry???

Airbot · 14 Aug 2011

arkhi said:

@Airbot

There was a mention of a requirement to create a registry key even though people siad "There wasn't". That's the point. Oh, and also the point that MS said that VVVV and PPPP are variables, not an actually key itself.

Actually, there isn't.

It says locate the subkey VVVVPPPP, and then create a new dword value inside of it. Doesn't say create the VVVVPPPP subkey itself at all.

TBoyd · 14 Aug 2011

I downloaded this hotfix in hopes that it would increase the data transfer rate of image files from a 8GB UDMA CFII card via a Lexar USB 2.0 reader. It created no improvement at all.

When I navigated to the HKLM\SYSTEM\CurrentControlSet\Control\usbstor\VVVVPPP subkey, I only found 4 different idVendors & id Products - none of which were my Lexar card reader. The USBSTOR for the Lexar is located in HKLM\SYSTEM\Control Set002\Control\DeviceClasses\{......} - So I hesitate to edit anything there.

I also have a virtual disk, so there is USB virtualization listed in my device manager as well.

I'm leaving this hotfix alone for now. - Not enough information from MS.

MilesAhead · 14 Aug 2011

xxxdannyxxx said:

Airbot said:

What's your point?

Ive tried now on several Hdds and Usbs and none show any significant increases at least on my devices

Danny

If they are blocking employee access to porn sites at Redmond then the guys probably need something to keep them awake. :)

edit: btw I have SIIG USB 3.0 Express card and if you factor in that Crystal Disk Mark considers 1000 KB a MB my quad core does sequential read at the rating of the WD caviar black 6 Gb/s drive. Namely around 126 MB/s (Crystal Disk Mark reads in the 130s since they consider 1000 kb a MB.)

My dual core with W7 reads and writes on a par with the capacity of the system drive. Typically sequential writes from the system drive to the HD in the USB 3.0 dock are in the 70 something MB/s range.. which is the capacity of the sending drive. I don't think there's any need to tweak it. :)

Mercurial · 14 Aug 2011

Its a trap!

GeneO · 14 Aug 2011

xxxdannyxxx said:

I looked at this a day or so ago but never had the VVVV/PPPP subkey even after installing the hotfix so didnt bother

Attachment 170137

Danny

The article says that for the ubstore/VVVVPPPP, the VVVV and PPPP are hexidecimal values that describe a USB device. In your case, ubstor/054C00C1 is one such USB device for which VVVV=054C and PPPP=00C1. So if you want to increase the transfer size for this device, you create the MaximumTransferLength dword in ubstor/054C00C1.

You don't literally create a ubstor/VVVVPPPP key and then create MaximumTransferLength in it. That will not do anything.

arkhi · 14 Aug 2011

Yup, because looking back at the KB article:

Locate and then click the following registry subkey:

HKLM\SYSTEM\CurrentControlSet\Control\usbstor\VVVVPPPP

VVVVPPPP are italicized, which obviously means those are variables, not to mention the note below it that says they represent hexadecimal values.

MilesAhead · 15 Aug 2011

Mercurial said:

Its a trap!

And the cheese smells moldy.