#11133 NORM 1.75-so: XO-1.75 test wireless performance
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bugtracker at laptop.org
Thu Feb 9 00:25:35 EST 2012
#11133: XO-1.75 test wireless performance
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Reporter: Quozl | Owner:
Type: task | Status: new
Priority: normal | Milestone: 1.75-software
Component: not assigned | Version: Development build as of this date
Resolution: | Keywords:
Next_action: test in build | Verified: 0
Deployment_affected: | Blockedby:
Blocking: |
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Comment(by greenfeld):
If there is a regression concern I need more information on how to
reproduce it and how the laptops were setup/spaced.
Local setup:
* Two XO-1.75 B1's, 11.3.1 os26
* One XO-1.5, 11.3.0 os883
* WNDR3700 AP w/ wired computer, running Fedora 14+iperf on a semi-decent
system. The 2.4 GHz AP channel was limited to 54 Mbps because one (non-
test) client I have cannot see the AP if set higher, but shouldn't matter
since XO's do not support 802.11n at this time.
* Systems kept ~1 meter from the AP or other XOs (for Ad-hoc) for testing
Local (non-office) testing with the above setup using the wired computer &
AP for an iperf server shows sampled throughput values ranging from ~14-16
Mbits/sec when using an XO-1.75 B1 with WPA2-PSK active, and ~15-17
Mbits/second using an XO-1.5. Disabling encryption did not noticeably
change the XO-1.5 results but did increase the XO-1.75's results to be
more in line with the XO-1.5.
Switching the XO-1.5 & 1.75 to talk to each other over ad-hoc using the
XO-1.75 as the iperf server resulted in tests showing ~13.5-15.0
Mbits/sec. I then tried two XO-1.75 B1's talking to each other on all
three Sugar ad-hoc network channels (1/6/11) with similar results.
I did not test two XOs talking through the AP as I do not know if that is
a concern with this ticket, and collision handling/backoff may vary from
AP to AP. I also do not know if my results are the expected limit,
although they seem higher than everyone else's in this ticket so far.
So there might be a ~1 MB/sec performance loss from XO-1.5 to 1.75 given a
short distance between devices, but to prove that needs more
analysis/samples/knowledge of what other 2.4 GHz users in the area are
doing/etc.
--
Ticket URL: <http://dev.laptop.org/ticket/11133#comment:12>
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