Speed Trials for Curl

Overview

These programs here are speed trials for ccurl, which is used as PoW(Proof of Work) in IOTA. These use same algorithm as ccurl except using thread , but with some speed tricks.

These programs executes a hash test ,PoW test for MinWeightMagnitude=15 in main routine and measure hash speed(kH/s).

Requirements

This requires

• linux (I didn't test on Windows.)
• gcc
• Intel SSE2 for pow_sse2.c

Installation

    $ git clone https://github.com/utamaro/curl_trials
	$ gcc -o pow_normal pow_normal.c -O3 -Wall
	$ ./pow_normal 
	$ gcc -o pow_sse2 pow_sse2 -O3 -Wall -msse2
	$ ./pow_sse2 

Performance

Using the following test environment...

* Compiler:  6.3.1 20170109 (GCC)
* Kernel: Linux 4.9.11-1-ARCH #1 SMP PREEMPT Sun Feb 19 13:45:52 UTC 2017 x86_64 GNU/Linux
* CPU:  Celeron(R) CPU G1840 @ 2.80GHz 
* Memory: 4 GB

This machine gets about 400kH/s on original ccurl on CPU PoW. By using '-O3' gcc option , it will be about 1.2MH/s.

and it gets about 320kH/s on GPU PoW.

Note that my machine is very very cheap one(about $30), and GPU is one which is embeded in CPU. It would be much faster if you use good PC or you have a good external GPU.

Normal Program (pow_normal.c)

This program is parallelized to 64 hashes as ccurl without threads. But was optimized by checking results of gprof.

$ time ./pow_normal 
count=24688640 kHash/sec: 1652 
PoWed hash is XPAITBTKUNSGAMYDJJQKSTSGSDIED9XVLDINYRRXDNNDBJYRH9NQPXFJFETIEMHOFZUZZQOLNTTJ99999
OK

real	0m14.942s
user	0m14.700s
sys	0m0.033s

about 1.6MH/s.

SSE2 (pow_sse2.c)

This program uses SSE2 in intel CPU by intrinsic and is parallelized to 128 hashes.

$ time ./pow_sse2
count=30755712 kHash/sec: 2677 
PoWed hash is RQIVYDWVCJ9EVMMZHCZT9IQVRQHXGWWOVUEHEFIZULGMAMGVQCEJRP9U9IWDVBB9NTBDCGY9DGKF99999
OK

real	0m11.489s
user	0m11.320s
sys	0m0.040s

about 2.7MH/s, x1.7 of the normal program.

Contribution

Improvements to the codebase and pull requests are encouraged.