- Mar 11, 2000
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Anand is getting iperf speeds of well over 500 Mbps.
http://www.anandtech.com/show/7085/the-2013-macbook-air-review-13inch/9
My desk and test area is in the corner of my office, which is where I put the ASUS 802.11ac router. Performance around my desk was always up around 533Mbps.
Move around 18 feet away but remain in the same room and measured performance dropped to 450Mbps. One set of walls and another 10 - 15 feet dropped performance to between 250Mbps - 340Mbps. Another set of walls without moving much further and I was looking at 200Mbps. When I went one more set of rooms away, or dropped down to a lower level, I saw pretty consistent falloff in performance - dropping down to 145Mbps. Note that my setup is pretty much the worst case scenario for longer distances. The AP isn’t centrally located at all. If I were setting up an 802.11ac network for max coverage, I’d probably see 300 - 400Mbps in most immediately adjacent rooms.
Real-world speeds were much slower, but it's not because of a limitation of the hardware. It is due to a software limitation in the settings as currently coded into Mountain Lion (and Mavericks). Hopefully this will be corrected by the time the new 802.11ac MacBook Pros come out, or else in the release version of Mavericks.
http://www.anandtech.com/show/7085/the-2013-macbook-air-review-13inch/10
The only way to get the full 533Mbps is by using a TCP window size that’s at least 256KB.
I re-ran my iPerf test and sniffed the packets that went by to confirm the TCP window size during the test. The results came back as expected. OS X properly scaled up the TCP window to 256KB, which enabled me to get the 533Mbps result:
OS X didn’t scale the TCP window size beyond 64KB, which limits performance to a bit above what I could get over 5GHz 802.11n on the MacBook Air. Interestingly enough you can get better performance over HTTP or FTP, but in none of the cases would OS X scale TCP window size to 256KB - thus artificially limiting 802.11ac.
If we can get 400+ Mbps real-world like Anand is getting in iperf, that'd be decent. My NAS maxes out at over 800 Mbps on Gigabit Ethernet, so half that over WiFi is nice, and a big improvement to what I'm getting over 802.11n.
http://www.anandtech.com/show/7085/the-2013-macbook-air-review-13inch/9
My desk and test area is in the corner of my office, which is where I put the ASUS 802.11ac router. Performance around my desk was always up around 533Mbps.
Move around 18 feet away but remain in the same room and measured performance dropped to 450Mbps. One set of walls and another 10 - 15 feet dropped performance to between 250Mbps - 340Mbps. Another set of walls without moving much further and I was looking at 200Mbps. When I went one more set of rooms away, or dropped down to a lower level, I saw pretty consistent falloff in performance - dropping down to 145Mbps. Note that my setup is pretty much the worst case scenario for longer distances. The AP isn’t centrally located at all. If I were setting up an 802.11ac network for max coverage, I’d probably see 300 - 400Mbps in most immediately adjacent rooms.
Real-world speeds were much slower, but it's not because of a limitation of the hardware. It is due to a software limitation in the settings as currently coded into Mountain Lion (and Mavericks). Hopefully this will be corrected by the time the new 802.11ac MacBook Pros come out, or else in the release version of Mavericks.
http://www.anandtech.com/show/7085/the-2013-macbook-air-review-13inch/10
The only way to get the full 533Mbps is by using a TCP window size that’s at least 256KB.
I re-ran my iPerf test and sniffed the packets that went by to confirm the TCP window size during the test. The results came back as expected. OS X properly scaled up the TCP window to 256KB, which enabled me to get the 533Mbps result:
OS X didn’t scale the TCP window size beyond 64KB, which limits performance to a bit above what I could get over 5GHz 802.11n on the MacBook Air. Interestingly enough you can get better performance over HTTP or FTP, but in none of the cases would OS X scale TCP window size to 256KB - thus artificially limiting 802.11ac.
If we can get 400+ Mbps real-world like Anand is getting in iperf, that'd be decent. My NAS maxes out at over 800 Mbps on Gigabit Ethernet, so half that over WiFi is nice, and a big improvement to what I'm getting over 802.11n.
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