What’s a Mosso Compute Cycle?

When I first launched usernamecheck.com I was on dreamhost. Within the first 48 hours with over 30k hits, they (very nicely I must say) said that I had outgrown them and I should maybe look at an alternative host for that site. I’d recently seen a great deal of press on Mosso, and their prices although very expensive compared to my bargain basement DH account didn’t seem out of this world, so I signed up. The only thing I was left worrying about was what was a “compute cycle”. With a mosso account they give you 10,000 compute cycles per month with the basic account, then every compute cycle over that costs you a penny. They give some ideas of what a compute cycle is and what sort of sites use what volume of cycles, but it’s still this strange intangible value that I had no idea what it would mean. They do try to explain it, but I never really understood or believed what was being said….

Using 10,000 compute cycles in a month is roughly equivalent to running a server with a 2.8 GHz modern processor for the same period of time.

I have no idea what a 2.8Ghz modern processor can do.

…same processing power as you’d get from a decent dedicated server or Amazon EC2 instance.

Excellent use of defining one ambiguous value with another one (as Rick here at work called it, it’s metric laundering).

Mostly, CPU processing time. However, compute cycles also account for the disk I/O your application’s operations consume.

There’s a lot of “abouts” and “mostlys”.

2 days ago I finished my first month with them, so I asked for a report of my daily compute cycle usage. I threw this into Pages with the same day stats from Google Analytics for Pageviews. My theory, I wanted to see what sort of correlation there was between page views and compute cycles.

There are a couple of things about the graph that need to be made very clear. There are 3 chunks of data that are all on different scales. Really the scale is irrelevant, I just want to show the pattern. There is a steep decline in the PPC value over the first few days, this is due to the very unique nature of the usernamecheck.com site, in that it is a single page site, that calls X number of AJAX requests to the server. In the early days of using Mosso the site went from checking 30 or so sites to it’s current level of 68. Hence the drop from 35 down to the now fairly consistent 10 PPC. Using the same assumption that 10 PPC is actually 680 PPC since 1 page views spawns at a minimum 68 requests that the server has to handle.

For me this gives me two very important things..

A: the ability to estimate how much I will be over or under for the month.

B: a good benchmark I can also use for new sites that I start hosting on this same Mosso account.

I would love it if this sort of data was available to a Mosso account holder easily. The page views per compute cycle for a historical period would be priceless to someone running a number of resold client sites - it would enable you to identify who was sucking all the compute cycles, that you could work with to better improve their processes. I’d be even happier if Mosso provided the last months graph for their entire universe. How cool would it be to have a graph that shows the X million of page views that Mosso clients get and the Y million compute cycles and then a second graph with the average PPC for the last month. That information would be invaluable to someone who wanted to sign up and I think would make more people take the plunge.