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This chapter introduces, describes, and explains the reasoning behind the programs and scripts that were used to realize the various test scenarios that were investigated.
Suck the webpage '/cgi-bin/html.cgi' from the specified IP address.
Usage: httpblast.sh [options] <IP address>
where: <IP address> is the IP address of the target machine to blast
options:
-p N pause for N microseconds between each grab (default:1/2 min)
-h this help screen
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This application by default will repeatedly suck the webpage /cgi-bin/html.cgi from the target machine twice per minute and run until explicitly terminated. The size of this transfer depends on the results of running the script on the target machine. The user must provide the IP address of the target machine on the command line. Optionally the user can specify a different pause value specified in microseconds.
Many embedded products can be configured through a web interface, this component simulates a user retrieving information about and/or configuring this device through the use of a CGI script and a web server running on the target device.
Usage: latency-server [options] <serial device> <FIFO>
Options:
--help, -h, -? Help, print this usage information
--verbose, -v Increase verbosity (max of 3)
--iterations N, -i N Specify the number of iterations, N
If specified the application will iterate N times then terminate,
otherwise it runs until Ctrl-C is pressed
--pause N, -p N After each iteration, pause for N microseconds (1s = 1,000,000us)
--report-iter N, -I N Generate a report every N iterations
--report-time N, -T N Generate a report every N seconds
--log <file>,-l <file> Duplicate output to a log file <file>
Pressing Ctrl-Z at any time will generate a report.
To start the transfer running, write something into the specified FIFO.
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This application writes a variable-length string to the serial port. When the target replies, the string will be returned prepended with the number of clock ticks, the CPU clock frequency, and the target's loadavg. In order for this to work the string must start with an open curly brace (i.e. '{') and must end with a closing curly brace (i.e. '}').
This component simulates getting an interrupt from hardware, reading data, passing the data along through several user-space applications (via FIFOs), and writing the data out to the serial port.
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