dt is conditionalized to run on Tru64 UNIX, HP-UX, SUN, ULTRIX, OSF/MK, QNX, Linux, SCO Unixware, and Windows operating systems. There are two versions of dt for Windows, the previous version which requires the Cygnus Solutions cygwin toolkit, and a native version found under the windows subdirectory (Debug and Release versions).
dt command lines are similar to the dd program, which is popular on most UNIX systems. It contains numerous options to give the user control of various test parameters.
dt has been used to successfully test disks, tapes, serial lines, parallel lines, pipes, and memory mapped files. In fact, dt can be used for any device that allows the standard open, read, write, and close system calls. Special support is necessary for some devices, such as serial lines, for setting up the speed, parity, data bits, etc.
Unpack the above archives via: "gzip -dc kit-name.tar.gz | tar xvf -"
The Work-In-Progress (WIP) versions of dt are located in my account on the production machines in ~rtmiller/Tools/dt.d-WIP. In this directory, you will find subdirectories for each operating system, for example aix5.3, solaris-sparc, linux2.6-x86, windows/Release, etc.
Rebuilding dt is fairly easy. After extracting the latest source kit, build dt via these steps:
% cd linux2.6-x86
% make -f ../Makefile.linux clean
% make -f ../Makefile.linux VPATH=..
Send mail to admin of this page: Robin.Miller@netapp.com
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Last modified: July 30th, 2009
I hope you find dt as useful as I have. This is usually one of the first tools I port to a new operating system, since it's an excellent diagnostic and performance tool.
% dt help
Usage: dt options...
Where options are:
if=filename The input file to read.
of=filename The output file to write.
pf=filename The data pattern file to use.
bs=value The block size to read/write.
log[tu]=filename The log file name to write.
t=truncate, u=unique (w/pid)
aios=value Set number of AIO's to queue.
alarm=time The keepalive alarm time.
keepalive=string The keepalive message string.
pkeepalive=str The pass keepalive msg string.
tkeepalive=str The totals keepalive msg string.
align=offset Set offset within page aligned buffer.
or align=rotate Rotate data address through sizeof(ptr).
capacity=value Set the device capacity in bytes.
dispose=mode Set file dispose to: {delete, keep, or keeponerror}.
dlimit=value Set the dump data buffer limit.
dtype=string Set the device type being tested.
idtype=string Set input device type being tested.
odtype=string Set output device type being tested.
dsize=value Set the device block (sector) size.
errors=value The number of errors to tolerate.
files=value Set number of tape files to process.
flow=type Set flow to: none, cts_rts, or xon_xoff.
incr=value Set number of record bytes to increment.
or incr=variable Enables variable I/O request sizes.
iodir=direction Set I/O direction to: {forward or reverse}.
iomode=mode Set I/O mode to: {copy, test, or verify}.
iotype=type Set I/O type to: {random or sequential}.
iotpass=value Set the IOT pattern for specified pass.
iotseed=value Set the IOT pattern block seed value.
history=value Set the number of history request entries.
hdsize=value Set the history data size (bytes to save).
min=value Set the minumum record size to transfer.
max=value Set the maximum record size to transfer.
lba=value Set starting block used w/lbdata option.
lbs=value Set logical block size for lbdata option.
limit=value The number of bytes to transfer.
flags=flags Set open flags: {excl,sync,...}
oflags=flags Set output flags: {append,trunc,...}
oncerr=action Set child error action: {abort or continue}.
noprogt=value Set the no progress time (in seconds).
noprogtt=value Set the no progress trigger time (secs).
notime=optype Disable timing of specified operation type.
parity=string Set parity to: {even, odd, or none}.
passes=value The number of passes to perform.
pattern=value The 32 bit hex data pattern to use.
or pattern=iot Use DJ's IOT test pattern.
or pattern=incr Use an incrementing data pattern.
or pattern=string The string to use for the data pattern.
position=offset Position to offset before testing.
prefix=string The data pattern prefix string.
procs=value The number of processes to create.
ralign=value The random I/O offset alignment.
rlimit=value The random I/O data byte limit.
rseed=value The random number generator seed.
records=value The number of records to process.
runtime=time The number of seconds to execute.
slice=value The specific disk slice to test.
slices=value The number of disk slices to test.
skip=value The number of records to skip past.
seek=value The number of records to seek past.
step=value The number of bytes seeked after I/O.
stats=level The stats level: {brief, full, or none}
trigger=type The trigger to execute during errors.
volumes=value The number of volumes to process.
vrecords=value The record limit for the last volume.
enable=flag Enable one or more of the flags below.
disable=flag Disable one or more of the flags below.
Flags to enable/disable:
aio POSIX Asynchronous I/O.(Default: disabled)
cerrors Report close errors. (Default: enabled)
compare Data comparison. (Default: enabled)
coredump Core dump on errors. (Default: disabled)
debug Debug output. (Default: disabled)
Debug Verbose debug output. (Default: disabled)
edebug End of file debug. (Default: disabled)
rdebug Random debug output. (Default: disabled)
tdebug Timer debug output. (Default: disabled)
dump Dump data buffer. (Default: enabled)
eof EOF/EOM exit status. (Default: disabled)
fsalign File system align. (Default: disabled)
funique Unique output file. (Default: disabled)
fsync Controls file sync'ing.(Default: runtime)
header Log file header. (Default: enabled)
hdump History dump. (Default: disabled)
htiming History timing. (Default: disabled)
lbdata Logical block data. (Default: disabled)
logpid Log process ID. (Default: disabled)
looponerror Loop on error. (Default: disabled)
microdelay Microsecond delays. (Default: disabled)
mmap Memory mapped I/O. (Default: disabled)
multi Multiple volumes. (Default: disabled)
noprog No progress check. (Default: disabled)
prefill Prefill read buffer. (Default: enabled)
pstats Per pass statistics. (Default: enabled)
raw Read after write. (Default: disabled)
retryDC Retry data corruptions.(Default: enabled)
sighup Hangup signal control. (Default: enabled)
stats Display statistics. (Default: enabled)
syslog Log errors to syslog. (Default: disabled)
timestamp Timestamp each block. (Default: disabled)
trigargs Trigger cmd arguments. (Default: enabled)
unique Unique pattern. (Default: enabled)
verbose Verbose output. (Default: enabled)
verify Verify data written. (Default: enabled)
Example: enable=debug disable=compare,pstats
Common Open Flags:
excl (O_EXCL) Exclusive open. (don't share)
ndelay (O_NDELAY) Non-delay open. (don't block)
nonblock (O_NONBLOCK) Non-blocking open/read/write.
direct (O_DIRECT) Direct disk access. (don't cache data).
fsync (O_FSYNC) Sync both read/write data with disk file.
rsync (O_RSYNC) Synchronize read operations.
sync (O_SYNC) Sync updates for data/file attributes.
large (O_LARGEFILE) Enable large (64-bit) file system support.
Output Open Flags:
append (O_APPEND) Append data to end of existing file.
dsync (O_DSYNC) Sync data to disk during write operations.
trunc (O_TRUNC) Truncate an existing file before writing.
Delays (Values are seconds, unless microdelay enabled):
cdelay=value Delay before closing the file. (Def: 0)
edelay=value Delay between multiple passes. (Def: 0)
rdelay=value Delay before reading each record. (Def: 0)
sdelay=value Delay before starting the test. (Def: 0)
tdelay=value Delay before child terminates. (Def: 1)
wdelay=value Delay before writing each record. (Def: 0)
retry_delay=value Delay before retrying operation. (Def: 5)
Numeric Input:
For options accepting numeric input, the string may contain any
combination of the following characters:
Special Characters:
w = words (4 bytes) q = quadwords (8 bytes)
b = blocks (512 bytes) k = kilobytes (1024 bytes)
m = megabytes (1048576 bytes) p = page size (4096 bytes)
g = gigabytes (1073741824 bytes)
t = terabytes (1099511627776 bytes)
inf or INF = infinity (18446744073709551615 bytes)
Arithmetic Characters:
+ = addition - = subtraction
* or x = multiplcation / = division
% = remainder
Bitwise Characters:
~ = complement of value >> = shift bits right
<< = shift bits left & = bitwise 'and' operation
| = bitwise 'or' operation ^ = bitwise exclusive 'or'
The default base for numeric input is decimal, but you can override
this default by specifying 0x or 0X for hexadecimal conversions, or
a leading zero '0' for octal conversions. NOTE: Evaluation is from
right to left without precedence, and parenthesis are not permitted.
Keepalive Format Control:
%b = The bytes read or written. %B = Total bytes read and written.
%c = Record count for this pass. %C = Total records for this test.
%d = The device name. %D = The real device name.
%e = The number of errors. %E = The error limit.
%f = The files read or written. %F = Total files read and written.
%h = The host name. %H = The full host name.
%k = The kilobytes this pass. %K = Total kilobytes for this test.
%l = Blocks read or written. %L = Total blocks read and written.
%m = The megabytes this pass. %M = Total megabytes for this test.
%p = The pass count. %P = The pass limit.
%r = Records read this pass. %R = Total records read this test.
%s = The seconds this pass. %S = The total seconds this test.
%t = The pass elapsed time. %T = The total elapsed time.
%i = The I/O mode (read/write) %u = The user (login) name.
%w = Records written this pass. %W = Total records written this test.
Performance Keywords:
%bps = The bytes per second. %lbps = Logical blocks per second.
%kbps = Kilobytes per second. %mbps = The megabytes per second.
%iops = The I/O's per second. %spio = The seconds per I/O.
Lowercase means per pass stats, while uppercase means total stats.
Default: %d Stats: mode %i, blocks %l, %m Mbytes, pass %p/%P, elapsed %t
or if pass statistics summary is disabled:
%d Stats: mode %i, blocks %L, %M Mbytes, pass %p/%P, elapsed %T
Log File Format Keywords:
%iodir = The I/O direction. %iotype = The I/O type.
%host = The host name. %pid = The process ID.
%user = The user name.
Example: log=dt_%host_%user_%iodir_%iotype-%pid.log
Pattern String Input:
\\ = Backslash \a = Alert (bell) \b = Backspace
\f = Formfeed \n = Newline \r = Carriage Return
\t = Tab \v = Vertical Tab \e or \E = Escape
\ddd = Octal Value \xdd or \Xdd = Hexadecimal Value
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)"
Time Input:
d = days (86400 seconds), h = hours (3600 seconds)
m = minutes (60 seconds), s = seconds (the default)
Arithmetic characters are permitted, and implicit addition is
performed on strings of the form '1d5h10m30s'.
Trigger Types:
br = Execute a bus reset.
bdr = Execute a bus device reset.
seek = Issue a seek to the failing lba.
cmd:string = Execute command with these args:
string dname op dsize offset position lba errno noprogt
args following cmd:string get appended to above args.
The first three options require Scu in your PATH.
Defaults:
errors=1, files=0, passes=1, records=0, bs=512, log=stderr
pattern=0x39c39c39, dispose=delete, align=0 (page aligned)
aios=8, dlimit=512, oncerr=continue, volumes=0, vrecords=1
iodir=forward, iomode=test, iotype=sequential, stats=full
iotseed=0x01010101, hdsize=32
--> Date: April 20th, 2009, Version: 16.20, Author: Robin T. Miller <--
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