Diskmax Help File
(08/19/96)

Diskmax is a Response Probe test to help you determine the maximum throughput 
of a disk drive. Diskmax does sequential, unbuffered reads of 64K records 
from a 20Mb file. Use Performance Monitor to help you analyze the result.

                                                                    
 -- For details on Response Probe, see:
    Windows NT Workstation Resource Guide
    Part 3, Optimizing Windows NT Workstation
    Chapter 11, Performance Monitoring Tools
    Response Probe

 -- For more information about using Performance Monitor to test disk 
    performance, see:
    Windows NT Workstation Resource Guide
    Part 3, Optimizing Windows NT Workstation
    Chapter 14, Detecting Disk Bottlenecks

To run Diskmax, 

1.  Install the required files from the Resource Kit CD onto the drive you
    want to test. (All files except for Workfile.dat are installed as part
    of the Performance Tools group by the CD Setup utility.)

    The following files are required:

    Probe.exe
    Probeprc.exe
    Diskmax.scr
    Diskmax.scp
    Diskmax.sct
    Workfile.dat

    By default, Probe.exe and Probeprc.exe are installed in the 
    \Perftool\Probe subdirectory. The Diskmax.sc* files are installed
    in the Perftool\Probe\Examples subdirectory. 

    Workfile.dat is not installed by the Setup utility, but you can copy it
    manually from the CD. Workfile.dat is a 20MB file filled with zeros 
    that Response Probe uses to simulate a workload file. You can use
    Workfile.dat or you can create a zero-filled file of any size by using
    the Createfile (Creatfil.exe) utility in the \Probe subdirectory. At 
    the command prompt, type: creatfil <filename> [<filesize>]. The filesize
    is optional; the default is 1024K bytes.)

2.  If you haven't done so already, you need to enable the Performance 
    Monitor disk counters.  Once you do, they remain enabled until you 
    disable them.

    To enable the disk counters, run the Diskperf utility that comes with 
    Windows NT. At the command prompt, type:

    diskperf -y 
    (for standard disk configurations)
   
    -or-

    diskperf -ye 
    (for stripe sets, mirror sets, or stripe sets with parity)

    
    then, restart the computer.

    If you want to disable the disk counters when your testing is complete,
    at the command prompt, type diskperf -n, then restart the computer.
                               

3.  Start a Performance Monitor log. If possible, write the log to a 
    different physical drive. Log the Logical Disk object at a one 
    second update interval.

4.  At the command prompt of the drive you want to test, change to the
    subdirectory where the .sc* files are stored (the default is Examples)
    and type: 

        <Path>Probe diskmax.scr 900

    Note: Diskmax must be run from the subdirectory where the .sc* files
          are stored. By default, the .sc* files are stored in the 
          \Probe\Examples subdirectory. To run Diskmax, copy all of 
          the required files to a single subdirectory or run from the
          directory where the .sc* files are stored.
    
5.  When the command prompt returns, stop the Performance Monitor log.

6.  Analyze the data from the test using the Response Probe output file, 
    Diskmax.out, and your Performance Monitor log. Use the following 
    Performance Monitor counters:

    Logical disk: Avg. Disk Bytes/Read
    Logical disk: Avg. Disk sec/Read
    Logical disk: Disk Read Bytes/sec
    Logical disk: Disk Reads/sec






    





