[wmf]

I would guess that Heroku runs ~29 dynos per m1.xlarge, so each dyno gets a minimum of ~1/7th of a core or ~366 MHz. Just because you can see 4 cores doesn't mean you can use them.

[exogen]

One day I noticed that Heroku gives you access to netstat, so I started trying to figure out the actual number.

Running this:

    heroku run "netstat -l | grep lxc | wc -l"

...seems to imply that it's actually 100 ± 25 dynos per instance.

(It's possible I could be entirely misunderstanding the netstat output, in which case someone please speak up.)

[jeremyjh]

Yes, I know that. The OP doesn't seem to know that. This is a problem, because the piece he is responding to in a large part is concerned with the meager resources provided by a single Dyno.