MacBook Pro Encountering High Latency
Edit:  Apple released two updates for the MBP this week, including an EFI update.  While neither update explicitly mentioned wireless connectivity, the update seems to have partially fixed the problem.  After installing both updates, I get a pretty consistent 3-5 ms ping with a very very occasional spike to 100.  At least it's much better than before.

In the meantime, the trick below still works if you want a 1 ms response instead.



There's an interesting tip from someone on Apple's discussion forums that can work as a workaround.

It appears that if the network card is inactive for more than 200 ms, it powers down and has to be powered up to send network traffic again, hence the random spikes.
But, if you can keep the network card active (at the cost of a small amount of CPU power and some extra traffic), then the latency goes away.

The command recommended by seanfromcolumbus was:

sudo ping -i .2 192.168.1.1

(The -i .2 specifies an interval of 200 ms)

Indeed, with this running, I get consistent results of &lt;2 ms.

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