pgs

An entropy source needing only a 32bit hardware cycle counter and 64bit operations. Weak entropy from the cycle counter avalanches nonlinearly through a dynamic nop loop, and finally passes through the ** mixer of David Blackman and Sebastiano Vigna. Pull requests for interesting platforms and other bitnesses are heartily welcomed!

Thanks to Walter Bright for the clean rdtsc asm, and for his long years of service in the C/C++/D community

Benchmarking

Homebrew

Testing pgs 🔬

Verifying uniqueness

000000 0x01e91c1851f792a1
020000 0x7a047eb12690b2f2
040000 0xd58b4eb9dc96f292
060000 0x9ceee78a2cc8aaff
080000 0x1e1c1bf5c217d511
100000 0x2ef46cd6ed9a6a0a

Each value unique ✓

Benchmarking latency

ns_avg | 8

Validating run lengths

zr_max | 32
zr_avg | 3

Validating bit count ratio

bcr_avg | 1.0000173

Validating bit pattern noncorrelation

trie_depth | 00 [1199991527, 1200008473] 1.0000
trie_depth | 01 [599989502, 600018971] 1.0000
trie_depth | 02 [299978121, 300028435] 1.0002
trie_depth | 03 [149981906, 150024904] 1.0003
trie_depth | 04 [74982427, 75018949] 1.0005
trie_depth | 05 [37482405, 37515605] 1.0009
trie_depth | 06 [18735808, 18762923] 1.0014
trie_depth | 07 [9366566, 9383156] 1.0018
trie_depth | 08 [4680840, 4694341] 1.0029
trie_depth | 09 [2337993, 2349104] 1.0048
trie_depth | 10 [1167970, 1175888] 1.0068
trie_depth | 11 [582581, 588563] 1.0103
trie_depth | 12 [290969, 294829] 1.0133
trie_depth | 13 [144697, 147947] 1.0225
trie_depth | 14 [72160, 74303] 1.0297
trie_depth | 15 [35757, 37448] 1.0473

Baselining with rdrand 🔬

Verifying uniqueness

000000 0x449548512efdc0a6
020000 0xffdaeef4800b54cf
040000 0x9f47d40863613b59
060000 0xb053e73312b003f3
080000 0xe1cc4483059d1aab
100000 0x813e72cf68b690cb

Each value unique ✓

Benchmarking latency

ns_avg | 100

Validating run lengths

zr_max | 31
zr_avg | 3

Validating bit count ratio

bcr_avg | 0.9999772

Validating bit pattern noncorrelation

trie_depth | 00 [1199960744, 1200039256] 1.0001
trie_depth | 01 [599941062, 600020100] 1.0001
trie_depth | 02 [299943387, 300020591] 1.0003
trie_depth | 03 [149948320, 150016287] 1.0005
trie_depth | 04 [74973322, 75016672] 1.0006
trie_depth | 05 [37485673, 37518946] 1.0009
trie_depth | 06 [18737796, 18760076] 1.0012
trie_depth | 07 [9364956, 9384283] 1.0021
trie_depth | 08 [4681709, 4694630] 1.0028
trie_depth | 09 [2338047, 2349022] 1.0047
trie_depth | 10 [1167370, 1176153] 1.0075
trie_depth | 11 [583248, 588948] 1.0098
trie_depth | 12 [291033, 295227] 1.0144
trie_depth | 13 [144994, 148091] 1.0214
trie_depth | 14 [72186, 74421] 1.0310
trie_depth | 15 [35865, 37386] 1.0424

PractRand

RNG_test using PractRand version 0.94
RNG = RNG_stdin64, seed = unknown
test set = core, folding = standard (64 bit)

rng=RNG_stdin64, seed=unknown
length= 512 megabytes (2^29 bytes), time= 3.4 seconds
  no anomalies in 226 test result(s)

rng=RNG_stdin64, seed=unknown
length= 1 gigabyte (2^30 bytes), time= 7.2 seconds
  no anomalies in 243 test result(s)

rng=RNG_stdin64, seed=unknown
length= 2 gigabytes (2^31 bytes), time= 14.3 seconds
  no anomalies in 261 test result(s)

rng=RNG_stdin64, seed=unknown
length= 4 gigabytes (2^32 bytes), time= 27.6 seconds
  no anomalies in 277 test result(s)

rng=RNG_stdin64, seed=unknown
length= 8 gigabytes (2^33 bytes), time= 54.3 seconds
  no anomalies in 294 test result(s)

rng=RNG_stdin64, seed=unknown
length= 16 gigabytes (2^34 bytes), time= 107 seconds
  no anomalies in 310 test result(s)

ENT

ent for urandom

Entropy = 1.000000 bits per bit.

Optimum compression would reduce the size
of this 8614019344 bit file by 0 percent.

Chi square distribution for 8614019344 samples is 0.92, and randomly
would exceed this value 33.81 percent of the times.

Arithmetic mean value of data bits is 0.5000 (0.5 = random).
Monte Carlo value for Pi is 3.141480279 (error 0.00 percent).
Serial correlation coefficient is -0.000012 (totally uncorrelated = 0.0).


ent for pgs

Entropy = 1.000000 bits per bit.

Optimum compression would reduce the size
of this 8614019344 bit file by 0 percent.

Chi square distribution for 8614019344 samples is 1.12, and randomly
would exceed this value 28.97 percent of the times.

Arithmetic mean value of data bits is 0.5000 (0.5 = random).
Monte Carlo value for Pi is 3.141543491 (error 0.00 percent).
Serial correlation coefficient is -0.000000 (totally uncorrelated = 0.0).