README.md

TurboHist: Fastest Histogram Construction

• ~0.18 - 0.90 cycles per byte
• 100% C (C++ compatible header) without inline assembly
• Both 32 and 64 bits supported
• Portable scalar functions faster than SIMD functions
• Up to 22 times faster than naive solution
• 🆕 (2022.01) more faster, beats even other very fast assembler functions

Benchmark:

• Single thread
• Realistic and practical benchmark with large files.
• No PURE cache benchmark

- Uniform/Skewed distribution:

• Uniform: enwik9
• Skewed: enwik9 bwt generated w. libdivsufsort
• 1GB zeros
• Accurate benchmarking with command "turbohist file -I15"

Benchmark Intel CPU: i7-9700K 3.6GHz gcc 11.2

Uniform distribution - enwik9 Text file, size=1.000.0000.000

Function	MB/s	Cycle/Byte	Language	Package
1:hist_1_8 naiv 8 bits	2761.01	1.3423	C	TurboHist
2:hist_4_8 4 bins/ 8 bits	2725.92	1.3249	C	TurboHist
3:hist_8_8 8 bins/ 8 bits	2850.05	1.2627	C	TurboHist
4:hist_4_32 4 bins/32 bits	3691.02	0.9660	C	TurboHist
5:hist_8_32 8 bins/32 bits	3867.26	0.9561	C	TurboHist
6:hist_4_64 4 bins/64 bits	4040.55	0.9103	C	TurboHist
7:hist_8_64 8 bins/64 bits	4053.37	0.9035	C	TurboHist
8:histr_4_64 4/64+run	3915.85	0.9668	C	TurboHist
9:histr_8_64 8/64+run	3916.51	0.9286	C	TurboHist
10:hist_4_128 4 bins/sse4.1	3643.20	1.0081	C	TurboHist
11:hist_8_128 8 bins/sse4.1	3607.06	0.9845	C	TurboHist
12:hist_4_256 4 bins/avx2	3522.27	1.0195	C	TurboHist
13:hist_8_256 8 bins/avx2	3542.25	1.0366	C	TurboHist
15:hist_8_64asm inline asm	4161.87	0.8787	inline asm	TurboHist
18:count2x64 inline asm	3963.91	0.9172	inline asm	Countbench
20:histo_ref	2702.57	1.3567	C	Ryg
21:histo_cpp_1x	1876.13	1.8236	C	Ryg
22:histo_cpp_2x	2664.78	1.5935	C	Ryg
23:histo_cpp_4x	2817.77	1.2944	C	Ryg
24:histo_asm_scalar4	3130.08	1.1609	asm	Ryg
25:histo_asm_scalar8	3353.08	1.0636	asm	Ryg
26:histo_asm_scalar8_var	3704.88	0.9856	asm	Ryg
27:histo_asm_scalar8_var2	4085.48	0.8913	asm	Ryg
28:histo_asm_scalar8_var3	4132.54	0.8870	asm	Ryg
29:histo_asm_scalar8_var4	4083.92	0.8970	asm	Ryg
30:histo_asm_scalar8_var5	4002.21	0.9025	asm	Ryg
31:histo_asm_sse4	3153.01	1.1445	asm	Ryg
32:memcpy	13724.29	0.2698	C

Skewed distribution - enwik9.bwt Text file, size=1.000.0000.000

Function	MB/s	Cycle/Byte	Language
1:hist_1_8 naiv 8 bits	1170.89	3.0642	C
2:hist_4_8 4 bins/ 8 bits	2707.74	1.3321	C
3:hist_8_8 8 bins/ 8 bits	2804.08	1.3208	C
4:hist_4_32 4 bins/32 bits	3118.54	1.1402	C
5:hist_8_32 8 bins/32 bits	3780.16	0.9714	C
6:hist_4_64 4 bins/64 bits	3646.25	0.9980	C
7:hist_8_64 8 bins/64 bits	3941.96	0.9282	C
8:histr_4_64 4/64+run	5061.62	0.7270	C
9:histr_8_64 8/64+run	5135.29	0.7229	C
10:hist_4_128 4 bins/sse4.1	3535.36	1.0365	C
11:hist_8_128 8 bins/sse4.1	3654.41	0.9791	C
12:hist_4_256 4 bins/avx2	3329.87	1.1022	C
13:hist_8_256 8 bins/avx2	3540.36	1.0343	C
15:hist_8_64asm inline asm	4047.74	0.9013	inline asm
18:count2x64 inline asm	3969.92	0.9262	inline asm
20:histo_ref	1182.61	3.0718	C
21:histo_cpp_1x	1213.42	2.9748	C
22:histo_cpp_2x	2115.60	1.7373	C
23:histo_cpp_4x	1801.97	2.0024	C
24:histo_asm_scalar4	3092.87	1.1561	asm
25:histo_asm_scalar8	3203.95	1.1139	asm
26:histo_asm_scalar8_var	3460.45	1.0422	asm
27:histo_asm_scalar8_var2	3659.61	0.9878	asm
28:histo_asm_scalar8_var3	3769.96	0.9569	asm
29:histo_asm_scalar8_var4	3996.75	0.8905	asm
30:histo_asm_scalar8_var5	4642.10	0.7719	asm
31:histo_asm_sse4	3091.36	1.1670	asm
32:memcpy	15594.28	0.2412	C

All zeros: size=1.000.0000.000

Function	MB/s	Cycle/Byte	Language
1:hist_1_8 naiv 8 bits	877.27	4.0805	C
2:hist_4_8 4 bins/ 8 bits	2650.84	1.3485	C
3:hist_8_8 8 bins/ 8 bits	2743.40	1.2994	C
4:hist_4_32 4 bins/32 bits	2978.83	1.2006	C
5:hist_8_32 8 bins/32 bits	3775.45	0.9555	C
6:hist_4_64 4 bins/64 bits	3411.11	1.0530	C
7:hist_8_64 8 bins/64 bits	3928.09	0.9342	C
8:histr_4_64 4/64+run	18998.87	0.1868	C
9:histr_8_64 8/64+run	19629.28	0.1869	C
10:hist_4_128 4 bins/sse4.1	3365.40	1.0717	C
11:hist_8_128 8 bins/sse4.1	3632.61	0.9950	C
12:hist_4_256 4 bins/avx2	3112.15	1.1576	C
13:hist_8_256 8 bins/avx2	3497.08	1.0205	C
15:hist_8_64asm inline asm	4089.97	0.8817	inline asm
18:count2x64 inline asm	3881.98	0.9158	inline asm
20:histo_ref	882.93	4.1072	C
21:histo_cpp_1x	873.20	4.1069	C
22:histo_cpp_2x	1720.19	2.0961	C
23:histo_cpp_4x	1866.99	2.0817	C
24:histo_asm_scalar4	2995.84	1.1942	asm
25:histo_asm_scalar8	3107.30	1.1618	asm
26:histo_asm_scalar8_var	3288.67	1.1143	asm
27:histo_asm_scalar8_var2	3290.92	1.0957	asm
28:histo_asm_scalar8_var3	3707.41	0.9763	asm
29:histo_asm_scalar8_var4	3988.01	0.9019	asm
30:histo_asm_scalar8_var5	14076.09	0.2564	asm
31:histo_asm_sse4	3020.32	1.1975	asm
32:memcpy	14057.53	0.2636	C

(bold = pareto) MB=1.000.000

• Ryg
  
• Countbench

Compile:

    make
 or
    make AVX2=1

Usage:

    turbohist [-e#] file [-I#] [-z]
    options:
    -e#     # = function numbers separated by ,
    -I#     # = number of iteration
            set to -I15 for accurate timings  
    -z      set read buffer to zeros

Examples:

    ./turbohist file
    ./turbohist -e1,7,9

Environment:

OS/Compiler (32 + 64 bits):

• Windows: MinGW-w64 makefile
• Linux amd/intel: GNU GCC (>=4.6)
• Linux amd/intel: Clang (>=3.2)
• Linux arm: aarch64 ARMv8: gcc (>=6.3)
• MaxOS: XCode (>=9) + Apple M1
• PowerPC ppc64le: gcc (>=8.0)

Last update: 01 JAN 2022