It's the other side of Chesterton's Fence: When you do understand why the fence was put there, you can remove it.

Too often people turn Chesterton's Fence into Frost's Fence: "Good fences make good neighbors" and refuse to think beyond that.

Because I was curious and others may be too, written by the man himself: https://rework.withgoogle.com/blog/the-roofshot-manifesto/

> If you are ever looking for someone to aspire to as a software engineer, you should aspire to be like Luiz.

This a million times.

I only interacted with Luiz a few times. They were eye-opening. He was so bright and, at the same time, so kind and supportive!

My team has improved some algorithms he and Jeff Dean popularized. When we presented to him, he asked us excellent questions. But, even though he was far up in our management chain, we never felt attacked nor judged, rather supported and empowered. I told my friend that it felt almost like talking to my grandfather when I was a young boy.

I also really appreciate some of his documents. They dealt with fairly general/philosophical topics (on the nature of software). They were so succinct and yet ... so deep and far-reaching! They left a long-lasting effect on me.

I admired Luiz's ability to connect with others. He showed me how not all truly smart people need to make a display of it.

I'm truly sad he died. And just after Bram...

"The Datacenter as a Computer: Designing Warehouse-Scale Machines" (3rd Edition) (2018) https://www.google.com/search?q=The+Datacenter+as+a+Computer... https://books.google.com/books?id=b951DwAAQBAJ

For datacenters, there are many design decisions for the power supplies and what voltages to use. The obvious solution is to use commodity PC hardware, so you have 120 volts AC to the computer's ATX power supply, which generates 12 volts DC, which is dropped to e.g. 1.5 volts on the motherboard to power the CPU. But this isn't the most efficient approach. You're going to get more efficiency with higher AC voltage (e.g. 208 volts). And you're going to get more efficiency with higher DC voltage (e.g. 48 volts). And also ATX power supplies aren't optimized for datacenters, since they have a lot of historical baggage and voltages that may not be needed (like standby). So there is a lot that can be done to squeeze more efficiency out of the power supplies.

Here's a Google presentation about changing to a 48V architecture: https://www.opencompute.org/files/External-2018-OCP-Summit-G...

Google has also used new circuitry for the DC-DC conversion. Here's a paper on their switched tank converter to drop 48 volts to 12 volts: https://storage.googleapis.com/pub-tools-public-publication-...