Re: AC: This wasn't a hardware flaw. This wasn't a mainframe flaw.
"...While great herds of commodity servers surely have a place, it is unlikely that they have a complexity, managability, or reliability advantage over mainframes for large workloads. It is quite possible that they also have no overall cost advantage...."
Google thinks it is more cost effective and reliable to have herds of commodity servers for their services, than a few large servers. Google has designed their system so it doesnt matter if a server breaks, they just insert a new cheap server. If you have 100 cheap servers that can switch roles anytime, you will have a better uptime than a single mainframe. Distributed beats centralized both in terms of costs and reliability and performance.
But sometimes, you can not distribute. Some workloads are inherently centralized and can not be parallellized. Google has embarassingly parallell workloads, so they can just use lot of COTS servers.
For banking, Mainframes are the norm. They can be replaced by a fleet of COTS servers, but no one has done it yet, as I know of. There will be years of R&D. Maybe it is easier to just use a Mainframe.
Another note. In banking, Mainframes are the norm. They are slow, have extremely slow cpus, but good I/O. Banking is doing lot of account updates like calculate interest rate, etc. Nothing sexy. Old, boring, dusty stuff. More, accountant stuff. It doesnt matter if your account gets updated 0.1 s later or so. Latency is not important. Much work is done in batches, and can wait another hour. Mainframes have good throughput, bad latency.
In finance, you never use Mainframes. In finance, you typically use Linux/Unix. You are doing real time high performance calculations. HFT. Quant. Math. Algorithmic trading. Linux has low latency, so that is important in some fields. Mainframes are too slow to do finance as they have very weak cpus, much weaker than x86 cpus. For instance, large stock exchanges typically run Linux/Unix. No stock exchange runs on Mainframes, they have too bad latency for that.
Banking: accountant stuff, boring. Needs to be reliable and just work. No requirements for bleeding edge performance. Simple calculations.
Finance: math, high performance stuff, complex calculations. Needs to be reliable and high performance. If you are faster than any one else, you get your order filled and you can earn money.