What's New as of August 24th, 2011
Changes For This Release
The following changes were made to dt Version 17.51:
-
Added enable=fsincr option allow incrementing file sizes. Basically, the 1st
file starts at 512 bytes, 2nd at 1024, etc. up to the limit you specified.
Options Added:
fsincr File size incrementing.(Default: disabled)
-
When using IOT data pattern, the maximum bad blocks reported is now 10.
One block was deemed to little, reporting all bad blocks was deemed too much!
Please use the maxbad=value parameter to change this default.
-
Added an option to allow dt to be stopped during long runs via checking for the
exisstance of a file.
Options Added:
stopon=filename Watch for file existance, then stop.
dt checks for this at the end of a pass, so after a write/read and verify.
Remember: When specifying multiple files and multiple directories, all of these must
be written, read, and verified to make up a single pass.
-
For those using microsecond delays, as part of I/O Tuning, bust wait code to obtain
small microsecond delays has been removed, since it consumed too much CPU! This was
very noticible on systems with a single CPU. Therefore, only millisecond delays are
possible. Remember, these delays occured between each read or write operation.
-
Please be aware, the format of no-progress messages has been enhanced to provide the
lba and file offset, to help with debugging:
dt (15762): No progress made for record 395 (lba 97288, offset 49811568) during write() on /var/tmp/dt.data-15762 for 6 seconds!
-
On Linux with AIO's enabled (implemented as threads), when dt terminates due to
a runtime or signal, the thread cancel type is changed to asynchronous to terminate
threads immediately, rather than deferred, to avoid a race when doing cleanup.
-
When doing file system testing with direct I/O (DIO), dt now ensures the block
sizes and data limit is modulo 512 bytes, which is required on Linux to avoid false errors.
-
On Windows, input values can now be 64-bit values (was limited to 32-bit previously).
-
For Windows, OS specific methods are now used to obtain the disk capacity and sector size.
This bypasses the previous internal logic previously used to determine the disk capacity,
necessary for random and reverse I/O.
Within NetApp, the updated dt kits are located @ URL:
http://web.rtp.netapp.com/~rtmiller/dt.html
External to NetApp, you can obtain dt kits from URL:
TBD
Send mail to admin of this page: Robin.Miller@netapp.com
To Robin's home page.
Last Modified: August 24th, 2011
Examples:
robin-ptc% dt version
--> Date: August 18th, 2011, Version: 17.51, Author: Robin T. Miller <--
robin-ptc% dt of=dt.data enable=fsincr files=10 limit=10m disable=stats dispose=keep
robin-ptc% ls -ls
total 48
4 -rw-r--r-- 1 rtmiller gopher 512 Aug 24 16:01 dt.data-00000001
4 -rw-r--r-- 1 rtmiller gopher 1024 Aug 24 16:01 dt.data-00000002
4 -rw-r--r-- 1 rtmiller gopher 1536 Aug 24 16:01 dt.data-00000003
4 -rw-r--r-- 1 rtmiller gopher 2048 Aug 24 16:01 dt.data-00000004
4 -rw-r--r-- 1 rtmiller gopher 2560 Aug 24 16:01 dt.data-00000005
4 -rw-r--r-- 1 rtmiller gopher 3072 Aug 24 16:01 dt.data-00000006
4 -rw-r--r-- 1 rtmiller gopher 3584 Aug 24 16:01 dt.data-00000007
4 -rw-r--r-- 1 rtmiller gopher 4096 Aug 24 16:01 dt.data-00000008
8 -rw-r--r-- 1 rtmiller gopher 4608 Aug 24 16:01 dt.data-00000009
8 -rw-r--r-- 1 rtmiller gopher 5120 Aug 24 16:01 dt.data-00000010
robin-ptc%
robin-ptc% dt of=dt.data bs=511 count=1 disable=stats flags=direct
dt: ERROR: Please specify a block size (511) modulo the device size of 512 bytes!
robin-ptc% dt of=dt.data bs=512 limit=1023 count=2 disable=stats flags=direct
dt: ERROR: Please specify a data limit (1023) modulo the device size of 512 bytes!
robin-ptc%