[discodave]

They just... don't retire them? The most expensive thing in a DC is the chips, so it's worth it to just build more datacenter space and keep the old ones around.

In 2019, before I left the EC2 Networking / VPC team, we were using M3 instances for our internal services... those machines were probably installed in 2013 or 2014, making them over 5 years old.

With the slowdown in Moore's law and chip speeds, I'd wager that team is still using those M3s now.

Eventually the machines actually start failing, so they need to be retired, but a large portion of machines likely make it to 10 years.

[aurareturn]

Isn't the most expensive thing power and cooling?

IE. if you replace the 5 year old Xeons with new ultra-efficient ARM chips, wouldn't that save you more power and cooling over x amount of time?

Genuine question.

[kaliszad]

According to James Hamilton who is a distinguished engineer at AWS no: https://perspectives.mvdirona.com/2010/09/overall-data-cente... and https://perspectives.mvdirona.com/2008/12/annual-fully-burde...

And you can watch him say it too: https://youtu.be/kHW-ayt_Urk?si=DKyw0-Pk-dhU5zFG&t=323

[temp0826]

They for sure can find a use internally for them. Hat-tip to the less-shiny teams like glacier that have to endlessly put out fires on dilapidated old s3 compute/array handmedowns.