-c <num>
--cpus=<num>
Set number of CPUs to use.
-d <dir>
--input-directory=<dir>
Set input directory. This option requires a single
parameter providing the directory name for where input
files are to be found. The default directory is the
current directory (.).
-F
--find-records
Find record files automatically This option instructs
btreplay to go find all the record files in the directory
specified (either via the -d option, or in the default
directory (.).
-h
--help
Show help and exit.
-i <basename>
--input-base=<basename>
Set base name for input files. Each input file has 3
fields:
1.
Device identifier (taken directly from the device name
of the
blktrace output file).
2.
btrecord base name — by default ``replay''.
3.
The CPU number (again, taken directly from the
blktrace output file name).
This option requires a single parameter that will override
the default name (replay), and replace it with the
specified value.
-I <num>
--iterations=<num>
Set number of iterations to run. This option requires a
single parameter which specifies the number of times to
run through the input files. The default value is 1
-M <filename>
--map-devs=<filename>
Specify device mappings. This option requires a single
parameter which specifies the name of a file contain
device mappings. The file must be very simply managed,
with just two pieces of data per line:
-
The device name on the recorded system (with the
'/dev/'
removed). Example: /dev/sda would just be sda.
-
The device name on the replay system to use (again,
without the
'/dev/' path prepended).
An example file for when one would map devices /dev/sda
and /dev/sdb on the recorded system to dev/sdg and sdh on
the replay system would be:
sda sdg
sdb sdh
The only entries in the file that are allowed are these
two element lines — we do not (yet?) support the notion of
blank lines, or comment lines, or the like.
The utility allows for multiple -M options to be supplied
on the command line.
-N
--no-stalls
Disable pre-bunch stalls. When specified on the command
line, all pre-bunch stall indicators will be ignored. IOs
will be replayed without inter-bunch delays.
-x <factor>
--acc-factor=<factor>
Specify acceleration factor. Default value is 1 (no
acceleration).
-v
--verbose
Enable verbose output. When specified on the command
line, this option instructs btreplay to store information
concerning each stall
and IO operation performed by
btreplay. The name of each file so created will be the
input file name used with an extension of .rep appended
onto it. Thus, an input file of the name sdab.replay.3
would generate a verbose output file with the name
sdab.replay.3.rep in the directory specified for input
files.
In addition, btreplay will also output to stderr the names
of the input files being processed.
-V
--version
Show version number and exit.
-W
--write-enable
Enable writing during replay. As a precautionary measure,
by default btreplay will not process write
requests. In
order to enable btreplay to actually write
to devices one
must explicitly specify the -W option.