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Windows 7: What is item Unknown(0x0) in xperf disk io?

18 Dec 2012   #1

Windows 7 Enterprise, 64bit
What is item Unknown(0x0) in xperf disk io?


I'm trying to find out what the file Unknown (0x0) is in disk IO in xperf trace. Below is information about the io read type to unknown (0x0).

My question is what is it? what is it used for? basic information and the reason it's value is usually greater than all the other files

IO Type: Read
Complete time: 25.506764217
IO time: 3026.318
disk service time: 744.603
pri: 0x03
QD/I: 1
io size: 65536
min offset : 0x000000138ca14000
max offset: 0x000000138ca23fff
process name: System
process: System (4)
thread id: 232
path name: Unknown (0x0)

My System SpecsSystem Spec
18 Dec 2012   #2

Windows 7 32 bit


Welcome to Windows Seven Forums.

To avoid a lot of Q & A about your hardware and OS configuration, please click on this link to
Edit System Specs

Filling this out, at least partially, will save a lot of time. Another advantage is when posting a new problem, the person answering can just click the My System Specs link in the bottom of your post. No need to search for the information.

If you have multiple systems just indicate that in the System Specs so that we know why many of the fields are blank.
My System SpecsSystem Spec
19 Dec 2012   #3

Windows 7 32 bit

Searching using these terms:
xperf disk path name: Unknown (0x0)

gets me a DOC file with some mumbo jumbo about path unknown is during system boot when the prefetcher is doing some yadda yadda. Anyway, it should be 3rd in the google results if you want to read it.
My System SpecsSystem Spec


 What is item Unknown(0x0) in xperf disk io?

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