4 ms·
>For one, insensitivity. There could be some victims even today, and you're talking casually about an event that will wipe out the Valley and S.F. I don't see
by monochr 12y ago
>For one, insensitivity. There could be some victims even today, and you're talking casually about an event that will wipe out the Valley and S.F.
I don't see why tragedy should stop us from thinking rationally about the situation.
>Second, most data centers are in tons of places for redundancy. Google, Microsoft, Amazon, etc etc. Even low cost providers like Linode And Digital Cloud have redundant data centers in 3-4 locations around the wolds.
The problem is that something between 1/3 to 1/2 of all connections to Asia pass through California[1].
>Third, ever done a ping to Australia? When most of your users are in the US, it's not really a good idea to have data travel halfway around the world and back. Even if anything else improves, the speed of light will remain constant.
The machine I have in Sydney pings 60ms to MIT on average. Caltech, UWS and UCLA are all down from there which probably has something to do with the Earthquake.
>Fourth, you think Valley based datacenters are not built to endure earthquakes? That they are just some dumb houses or something with racks inside?
Are the cables made of magic unicorn hair that doesn't break? Because if [2] or [3] happens I don't care how much like a bunker your data center is, it's not talking to anyone. Which also leads back to the problems in number 2, namely, far too much bandwidth passes through California for how dangerous it is.
[1] https://www.technocrates.org/wp-content/uploads/2012/10/submarine-cable-map.jpg https://www.technocrates.org/wp-content/uploads/2012/10/subm...
[2] http://www.geerassociation.org/GEER_Post%20EQ%20Reports/Italy_2009/It09_Ch02_clip_image002_0000.jpg http://www.geerassociation.org/GEER_Post%20EQ%20Reports/Ital...
[3] http://www.cloacina.org/blog/wp-content/uploads/2012/03/cracked-pipe-photo.jpg http://www.cloacina.org/blog/wp-content/uploads/2012/03/crac...
- dekhn 12y agoI'm curious how your pings are basically as fast as the speed of light. Do you have a direct fiber cable between sydney and MIT with no repeaters or intermediate switching equipment, and photons that travel at twice the speed of light? Because nobody does. Ping measures round trip time, not point to point. Distance from Sydney NSW to Boston, MA: 16,230 km http://en.wikipedia.org/wiki/Optical_fiber http://en.wikipedia.org/wiki/Optical_fiber: "From this information, a simple rule of thumb is that a signal using optical fiber for communication will travel at around 200,000 kilometers per second. " Some basic math: (16 230 km) / (200 000 (kilometers per second)) = 81.15 milliseconds that's one way. You should be seeing no bnetter than 160ms, and even that is idealized because there is switching equipment that induces delays.
- monochr 12y ago$ sudo ping -f www.mit.edu PING e9566.b.akamaiedge.net (184.24.249.86) 56(84) bytes of data. ....^C --- e9566.b.akamaiedge.net ping statistics --- 728 packets transmitted, 724 received, 0% packet loss, time 10177ms rtt min/avg/max/mdev = 25.935/38.167/131.406/16.421 ms, pipe 11, ipg/ewma 13.999/35.015 ms http://www.geoiptool.com/en/?IP=184.24.249.86 http://www.geoiptool.com/en/?IP=184.24.249.86 My the server I'm testing this on is in Sydney, the server info on the geoip says I'm pinging somewhere in Cambridge, Massachusetts.
- dekhn 12y agoThere are many explanations which are simpler, that don't require faster than light photons. In particular, your network path is sending you to a server which is in australia. $ host 184.24.249.86 86.249.24.184.in-addr.arpa domain name pointer a184-24-249-86.deploy.static.akamaitechnologies.com. trimmed mtr output: 19. sun1-ge5-0.gw.optusnet.com.au 57.1% 8 186.4 184.9 182.1 186.4 2.3 20. 198.142.144.70 42.9% 8 186.9 182.6 180.3 186.9 2.9 21. sun1-ge12-0-0-500.gw.optusnet.com.au 0.0% 7 179.7 180.3 179.5 182.3 0.8 a184-24-249-86.deploy.static.akamaitechnologies.com 22. 198.142.144.70 0.0% 7 185.6 184.6 179.5 194.2 4.9 a184-24-249-86.deploy.static.akamaitechnologies.com 23. a184-24-249-86.deploy.static.akamaitechnologies.com 0.0% 7 185.1 184.0 178.8 187.8 2.8 that's a cache of MIT's web site hosted in Australia (Akamai edge cache) http://research.microsoft.com/en-us/um/people/ratul/akamai.html http://research.microsoft.com/en-us/um/people/ratul/akamai.h... geoip is worthless in many situations, this being one of them.
- dekhn 12y agoAlso, most routers implement ICMP on a slow path (not on the data plane) so the reported latency can be higher than the path latency.
- coldtea 12y ago>I don't see why tragedy should stop us from thinking rationally about the situation. I don't see why thinking rationally would entail talking without any sensitivity and humanity -- which is what I complained about, not the "thinking rationally" part itself. >The machine I have in Sydney pings 60ms to MIT on average. Doesn't 60ms sound quite bad as the optimal average one can have? >Are the cables made of magic unicorn hair that doesn't break? No, just that buildings are make of scientific structural construction that endures and absorbs earthquake pressure. As for the cables, that's an easier problem to solve, and it will be more localized.
- deleted 12y ago[deleted]