jgreco
Resident Grinch
- Joined
- May 29, 2011
- Messages
- 18,680
Well really "watts per usable square feet" or "watts per equipment square feet" but you can take your pick and still end up being "right" FSVO "right".
Measuring this gets really dicey because racks are not a fixed size. Back when I started this stuff it wasn't uncommon to have a 24" deep rack, and I remember even late into the '90's there were colo sites with crummy specs. I think it was GTE/Genuity at 216 Jackson that had 26U 28" deep racks, because they had a low ceiling and raised floor. But racks are now often 40" deep, and may be 58U or even more.
This Equinix blog post discusses it in somewhat more detail (obDisclosure: customer). The thing to note is that the scale isn't linear. That red line for comms gear goes from about 500W/sf in 1993 to around 10000W/sf around 2015. I realize we're a little off-topic here, but past experience suggests that some members of the audience here find this stuff interesting.
Measuring this gets really dicey because racks are not a fixed size. Back when I started this stuff it wasn't uncommon to have a 24" deep rack, and I remember even late into the '90's there were colo sites with crummy specs. I think it was GTE/Genuity at 216 Jackson that had 26U 28" deep racks, because they had a low ceiling and raised floor. But racks are now often 40" deep, and may be 58U or even more.

This Equinix blog post discusses it in somewhat more detail (obDisclosure: customer). The thing to note is that the scale isn't linear. That red line for comms gear goes from about 500W/sf in 1993 to around 10000W/sf around 2015. I realize we're a little off-topic here, but past experience suggests that some members of the audience here find this stuff interesting.