2011-06-07

The link between outage and more downloads

Skype is down again, and this happens too often the last years.
But the funny thing is, at the same time the number of downloads of the Skype application raises tremendously. See the dramatic drop down of the users online on the red curve, and the very visible bent in the blue download curve. Why could this be?
I think that a lot of people thought that the Skype problem was their computer or Skype client crashing. Therefore they tried to install a new version, probably to no avail!

4 comments:

Myroslav Opyr said...

If you take a closer look at the graph, you'll notice that downloads ramped up earlier in time then Skype Cloud disassembled.

As far as I know many Windows users updated earlier today, and Skype worked fine for some time. Then it started crashing. Crashing is bad for Skype Cloud as it is loosing Supernodes, and crashes increase load on those Supernodes that left with restarted clients that try to rebind to the cloud.

After restart Windows Skype client crashed again and after another restart - again. It is easy to go the simplest route for Windows uses - reinstall. And probably many went to Skype.com to download latest version with the hope that it will not crash.

I have Linux Skype and mine client worked throughout outage. It was interesting that I was displayed offline, as if I'm disconnected from the Skype Cloud, and all my contacts appeared offline to me, but messages continued to propagate, at least inside my company LAN from those who hadn't restarted their Skype clients and left them running in "offline" mode attempting to reconnect.

Jean Mercier said...

Hello Myroslav,

I agree with you that downloads ramp up earlier in time then the Skype Cloud disassembled ON THE GRAPH.

Why do I say "on the graph"? Well, the way Skype calculates the number of downloads and the number of users online is different. Downloads can be known almost instantly, because it is a counter on the download servers, summing the data if they have to count on several servers, and ready they are.

The number of users online is some kind of Skype algorithm, and is approximate. They dig in the cloud through some iteration I guess. This takes some time.

On the other hand, the Japanese site from which I copy the graph (see links on the right side of my blog) takes the number of downloads from the Skype RSS feeds (see also on the right side of my blog, and I am sure). The number of users online is probably taken from his Skype client (also not sure). There is also probably some delay between one number and the other.
(And I see now that he has a mistake on his graph: the number of downloads should be multiplied by 10).
I think and am almost sure the “earlier ramp” is only due to this. I never saw such a sudden increase in downloads without an evident explanation (like a Skype outage).

But, we agree on the fact that Windows users tried to install a new version hoping to solve the problem! This can only mean that for a lot f people, Skype is “vital”, and they don’t want to stay without it!

Thanks for your comments, I didn’t notice the small “delay”!

Myroslav Opyr said...

As soon as I got reports from my colleagues that Skype started crashing, I visited the graph. It was before total Skype Cloud Disassembly happened.

I noticed than that curve should be much higher as for that time of a day (Europe usage increasing and America starting to wake up), but curve was flat. It was indication that Skype Cloud is missing inhabitants.

Soon after that it collapsed completely.

I was monitoring my Skype client Cloud Count and it was seeing newer number 2-5 minutes before http://nyanyan.to/skype/40hr_chart.php. And the Count in my Skype Client reflected health of the cloud pretty good, thus I'm sure that its accuracy is something like 15 minutes.

The graph we see at nyanyan.to hadn't caught a couple of Cloud splits that my Skype Client participated. I've been observing something like 85k Count for a brief period of time.

As Skype becomes more and more important Skype Monitoring Network becomes more and more interesting. Such simple metrics as Skype Cloud Count appears to be very informative.

Daniel Serodio said...

Hello Jean,

I'm writing about Skype for my MBA dissertation, and I was wondering if you could share the spreadsheets you use to make these awesome graphs. I'm mostly interested in number of registered users, simultaneous connected users, paying users, and Skype minutes.

If you have also compiled financial numbers like revenue or profit, that'd be awesome, too.

You can reach me at Gmail, my username is dserodio

Thanks in advance,
Daniel Serodio