Data Test Program (dt) March 25, 2003

What's New as of March 25, 2003

Changes For This Release

This is a minor release of dt, which includes several bug fixes and a few new features.

The following changes were made to dt Version 14.28:

Ported to HP-UX (actually done about a year ago). The latest updates for HP-UX are to use DIOC_DESCRIBE or SIOC_INQUIRY to obtain device information, set maximum capacity, and setup the device type automatically.
Slice & Dice: Previously, a slices=value option was added. Now, a slice=value option has been added so you can tell dt which slice (range of blocks) to do I/O to. This is a handy feature for testing shared storage in a cluster (where each cluster member can do I/O to it's own slice).

Prefix Option: To help generate unique data in each record, a prefix="string" option has been added. You can specify your own generated string, or use special format control's built into 'dt' to create a unique prefix:

        Prefix Format Control:
	    %d = The device name.          %D = The real device name.
	    %h = The host name.            %H = The full host name.
	    %p = The process ID.           %P = The parent PID.
	    %u = The user name.

	    Example: prefix="%u@%h (pid %p)"

Improved Performance: The addition of new data pattern features (lbdata and IOT) caused a regression of data compare performance. By optimizing this code path, a 23-24% improvement was observed on my Alpha DS20-E with Ultra-3 disks (your mileage may vary :-).

Please see attached examples for use of these new options.

Within HP, the updated dt kits are located @ URL:

http://www.zk3.dec.com/~rmiller/dt.html

External to HP, you can obtain dt kits from URL:

http://www.bit-net.com/~rmiller/dt.html

Send mail to admin of this page: Robin.Miller@hp.com

To Robin's home page.

Last Modified: March 25th, 2003

Examples:

% dt of=/dev/rdisk/dsk25c bs=64k limit=1m  slices=3 prefix="%u@%h (pid %p)" disable=pstats
dt (3996): End of Write pass 0, records = 16, errors = 0, elapsed time = 00m00.68s
dt (3998): End of Write pass 0, records = 16, errors = 0, elapsed time = 00m00.70s
dt (3997): End of Write pass 0, records = 16, errors = 0, elapsed time = 00m00.71s
dt (3996): End of Read pass 1, records = 16, errors = 0, elapsed time = 00m00.65s

Total Statistics (3996):
     Output device/file name: /dev/rdisk/dsk25c (Device: BF01863644, type=disk)
     Type of I/O's performed: sequential (forward)
      Slice Range Parameters: position=0 (lba 0), limit=1048576
      Current Slice Reported: 1/3
    Data pattern prefix used: 'rmiller@wisdom (pid 3996)'
   Data pattern read/written: 0x39c39c39
     Total records processed: 32 @ 65536 bytes/record (64.000 Kbytes)
     Total bytes transferred: 2097152 (2048.000 Kbytes, 2.000 Mbytes)
      Average transfer rates: 1553446 bytes/sec, 1517.037 Kbytes/sec
     Number I/O's per second: 23.704
      Total passes completed: 1/1
       Total errors detected: 0/1
          Total elapsed time: 00m01.35s
           Total system time: 00m00.00s
             Total user time: 00m00.08s
               Starting time: Tue Mar 25 14:53:02 2003
                 Ending time: Tue Mar 25 14:53:03 2003

dt (3998): End of Read pass 1, records = 16, errors = 0, elapsed time = 00m00.65s

Total Statistics (3998):
     Output device/file name: /dev/rdisk/dsk25c (Device: BF01863644, type=disk)
     Type of I/O's performed: sequential (forward)
      Slice Range Parameters: position=12139546624 (lba 23710052), limit=1048576
      Current Slice Reported: 3/3
    Data pattern prefix used: 'rmiller@wisdom (pid 3998)'
   Data pattern read/written: 0x0f0f0f0f
     Total records processed: 32 @ 65536 bytes/record (64.000 Kbytes)
     Total bytes transferred: 2097152 (2048.000 Kbytes, 2.000 Mbytes)
      Average transfer rates: 1553446 bytes/sec, 1517.037 Kbytes/sec
     Number I/O's per second: 23.704
      Total passes completed: 1/1
       Total errors detected: 0/1
          Total elapsed time: 00m01.35s
           Total system time: 00m00.00s
             Total user time: 00m00.08s
               Starting time: Tue Mar 25 14:53:02 2003
                 Ending time: Tue Mar 25 14:53:03 2003

dt (3997): End of Read pass 1, records = 16, errors = 0, elapsed time = 00m00.66s

Total Statistics (3997):
     Output device/file name: /dev/rdisk/dsk25c (Device: BF01863644, type=disk)
     Type of I/O's performed: sequential (forward)
      Slice Range Parameters: position=6069773312 (lba 11855026), limit=1048576
      Current Slice Reported: 2/3
    Data pattern prefix used: 'rmiller@wisdom (pid 3997)'
   Data pattern read/written: 0x00ff00ff
     Total records processed: 32 @ 65536 bytes/record (64.000 Kbytes)
     Total bytes transferred: 2097152 (2048.000 Kbytes, 2.000 Mbytes)
      Average transfer rates: 1516013 bytes/sec, 1480.482 Kbytes/sec
     Number I/O's per second: 23.133
      Total passes completed: 1/1
       Total errors detected: 0/1
          Total elapsed time: 00m01.38s
           Total system time: 00m00.00s
             Total user time: 00m00.08s
               Starting time: Tue Mar 25 14:53:02 2003
                 Ending time: Tue Mar 25 14:53:03 2003

% dt of=/dev/rdisk/dsk25c bs=64k slices=25 slice=13 disable=pstats enable=debug
dt (4000): DEVGETINFO Capacity: 35565080 blocks.
dt (4000): Data limit set to 18209320960 bytes (17365.762 Mbytes), 35565080 blocks.
dt (4000): Slice 13 Information:
		 Start: 8740472832 offset (lba 17071236)
		   End: 9468845568 offset (lba 18493839)
		Length: 728372736 bytes (1422603 blocks)
		 Limit: 728372736 bytes (1422603 blocks)
dt: Attempting to open output file '/dev/rdisk/dsk25c', open flags = 01 (0x1)...
dt: Output file '/dev/rdisk/dsk25c' successfully opened, fd = 3
dt: Data limit set to 18209320960 bytes (17365.762 Mbytes), 35565080 blocks.
dt: Allocated buffer at address 0x140026000 of 65540 bytes, using offset 0
dt: Using data pattern 0x39c39c39 for pass 1
dt: Record #11115, Writing a partial record of 5632 bytes...
dt: End of Write pass 0, records = 11114, errors = 0, elapsed time = 02m18.36s
dt: Closing file '/dev/rdisk/dsk25c', fd = 3...
dt: Attempting to reopen file '/dev/rdisk/dsk25c', open flags = 0 (0)...
dt: File '/dev/rdisk/dsk25c' successfully reopened, fd = 3
dt: Record #11115, Reading a partial record of 5632 bytes...
dt: End of Read pass 1, records = 11114, errors = 0, elapsed time = 02m59.35s
dt: Closing file '/dev/rdisk/dsk25c', fd = 3...

Total Statistics:
     Output device/file name: /dev/rdisk/dsk25c (Device: BF01863644, type=disk)
     Type of I/O's performed: sequential (forward)
   Data pattern read/written: 0x39c39c39
     Total records processed: 22228 @ 65536 bytes/record, 2 partial
     Total bytes transferred: 1456745472 (1422603.000 Kbytes, 1389.261 Mbytes)
      Average transfer rates: 4584565 bytes/sec, 4477.114 Kbytes/sec
     Number I/O's per second: 69.961
      Total passes completed: 1/1
       Total errors detected: 0/1
          Total elapsed time: 05m17.75s
           Total system time: 00m03.56s
             Total user time: 01m01.80s
               Starting time: Tue Mar 25 14:55:08 2003
                 Ending time: Tue Mar 25 15:00:25 2003

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