This command-line tool allows a developer or system
administrator to monitor that occur
while an application is running. PFMon is especially useful to
trace hard page faults. (You can easily resolve soft page faults
with Virtual Memory Manager.) A sustained high rate of hard page
faults might indicate a shortage of memory and can cause a disk
bottleneck. Use PFMon to trace the source and number of page faults
in a and display the
data in the command window, write it to a log file, or both.
A page is a fixed amount of data. When you run a program, the
microprocessor stores pages of data that it predicts you will need
in main memory, also known as RAM. Pages of data that are not
needed are left on your storage device, such as your hard disk.
A page fault occurs when a process refers to a virtual memory
page that is not in the working set (the physical memory visible to
the program) in main memory.
There are two kinds of page faults: soft and hard. A soft
page fault occurs when a process refers to a virtual memory
page that is not in the working set, but does not require that the
page be retrieved from disk. This can happen when the page is on
the standby list in main memory or when the page is being shared
with another process. A hard page fault occurs when a
virtual memory page is not found in main memory and must therefore
be retrieved from disk.
Neither type of page fault is an error.
Hard page faults indicate that your program is reading from and
writing to disk. A rise in the number hard page faults generated by
a specific program increases the possibility of a disk bottleneck.
PFMon helps you determine the number, type, and source of soft and
hard page faults that your application generates.
