autotest: create WiFiPerf suite

autotest: create WiFiPerf suite

This suite checks upstream+downstream UDP+TCP performance w/ and w/o
security and w/ and w/o power save.  We use iperf exclusively so we
can control bandwidth for udp tests and for consistency with future
additions to collect QoS-related data.  UDP bandwidth values chosen
to cover channel bandwidth range and also overload channel.

Note this doesn't remove any performance tests in MatFunc or SecMat; we
may want to do that but will keep that separate.

BUG=chromium-os:5719, chromium-os:9424
TEST=run WiFiPerf suite and check results (note "Perf" is ambiguous so must specify "WiFiPerf" on the cmd line)

Committed: http://chrome-svn/viewvc/chromeos?view=rev&revision=abaa496

[Sam Leffler, 2011-01-07 21:29:55]

as discussed, but only throughput (no latency measurements)

[Paul Stewart, 2011-01-07 22:25:44]

LGTM with or without nits.

These files are missing comments at in each test explaining (in this case in
very brief terms) what they are meant to do.

http://codereview.chromium.org/6128002/diff/1/server/site_tests/network_WiFiP...
File server/site_tests/network_WiFiPerf/051Perf11g_WEP (right):

http://codereview.chromium.org/6128002/diff/1/server/site_tests/network_WiFiP...
server/site_tests/network_WiFiPerf/051Perf11g_WEP:9: #                         
"authmode":"open", "wepmode":"on",
Is this a TODO?

http://codereview.chromium.org/6128002/diff/1/server/site_tests/network_WiFiP...
server/site_tests/network_WiFiPerf/051Perf11g_WEP:44: # XXX mixed streams
This one could certainly be formatted as a TODO.

[Sam Leffler, 2011-01-10 16:38:06]

PTAL.  I responded to your comments, fixed TKIP+HT tests (to skip since hostapd
won't configure it), and trimmed the runtimes of many tests to hopefully make
this suite more useful.

The one big hole is lack of channel coverage in 5Ghz but that's painful to do
right w/o proper regulatory support to return the channel list and/or change
regdomain so we can reach all bands.

[Paul Stewart, 2011-01-10 16:56:44]

LGTM