How do I interpret these strange JavaScript timestamps from mobile phones?

I maintain a JavaScript library that measures web page load times (http://github.com/lognormal/boomerang) and sends them to my server in a beacon. Some of the times it sends back are relative (end-start) while others are absolute (new Date().getTime())

For the most part the absolute timestamps I see make sense, and are within a few seconds of the request time. Then every now and then I see some extremely absurd timestamps and I don't know what to make of them. Here's a sample:

112731879   (Safari 4 on Mac OS X 10.4.11 (PPC))
574766408   (Android 2.3.1)
6855660455  (iOS 4.2.1 on iPad)
5000        (Safari 3.1)
356902853   (Mobile Safari 4.0.4 on iOS 3.2 (iPad))
133643085   (Mobile Safari 5.0.2 on iPhoneOS 4.2.1 (iPod))
2775235876  (Mobile Safari 4.0.5 on iPhoneOS 4.1 (iPod))

While it looks like these are mostly mobile devices, there are a couple in there that aren't. Note that all these timestamps should be milliseconds, so there should be 13 digits for anything recent.

I've searched the net, but I either don't have a good search query, or there's nothing out there that talks about this. I've tested out my own iOS devices and get 13 digit timestamps, so I have no idea what these could be. Any ideas/suggestions for where to look or what to look for would be appreciated.

I understand that some of these request might just be fake, but the rest of the user's browsing pattern suggests that they're legitimate users of a website.

Answers


Any chance this could be related to the unreliable system clock that Date() is based on? The new performance.now() API is supposed to help address such issues (though I don't know how common this issue should be in the real world, or why mobile would be affected so drastically.)

http://gent.ilcore.com/2012/06/better-timer-for-javascript.html


Need Your Help

How can one setup a version control system on a local network, without a server?

visual-studio svn version-control local-network

Edit: Ok so I learned that I guess I need an distributed source control, however are there any UI based ones, and do they allow you to merge with other users on the network?

Cannot find module when attempting to automatically import node.js modules

node.js file-io

I have a directory tmp that has 3 test node.js modules [mod0.js, mod1.js, mod2.js].