Raspberry Pi Zero

[2020/12]

What other computer system consumes no more than 1 watt of power and costs $~10?

Though not its intended purpose, RPI0 is way too slow as a desktop computer. RPI0 is fast enough to run GUI, but then most complex programs will run tortuously slow. Some programs ran faster on 25Mhz 80486. A few programs do run fast enough, similar programs don't. Lack of L1 cache is what mainly cripples RPI0 apparently.

ARM had (past tense) a reputation for being sleek and efficient. Let's look at junk that has accumulated into instruction-set of RPI0's ARM, from Linux /proc/cpuinfo:

processor   : 0
model name  : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS    : 797.66
Features    : half thumb fastmult vfp edsp java tls 
                                           ^^^^
                                        -- JUNK --

benchmarks

Speed of compiling GNU emacs

[2020/12]

Not equal comparisons, variously compiled emacs versions 24..27, emacs may have been compiled in temp RAM on PCs having ample memory.

  ~40 sec   PC Intel Goldmont+ Atom J5005, 2.8Ghz, 4 cores
  ~80 sec   PC Intel Core 2 Duo, 2.2Ghz, 2 cores
 ~115 sec   PC AMD64X2 2.2Ghz, 2 cores
 ~470 sec   Mac Mini PowerPC G4 7450 1.33Ghz
 2613 sec   Raspberry Pi Zero W, 1Ghz 32-bit ARMv6, 1 core