Equi-X is a CPU-friendly client puzzle with fast verification and small solution size (16 bytes). It is based on Equihash(60,3) with two major changes:
- Blake2b hash function is replaced with HashX.
- XOR is replaced with modular addition.
An Equi-X solution for nonce X is a set of eight 16-bit indices i0, ..., i7 such that:
HX(i0) + HX(i1) + HX(i2) + HX(i3) + HX(i4) + HX(i5) + HX(i6) + HX(i7) = 0 (mod 260)
where HX is a HashX function generated for nonce X. Equi-X is therefore a variant of the subset sum problem. Each nonce value provides 2 solutions on average.
Equi-X also has additional requirements that prove that the solution was found using the Wagner's algorithm. See the Equihash paper for details.
H(0x6c31) = 0xcfa5375c0a7f5d7 \
(+) = 0xa73d9777f110000 \
H(0x8803) = 0xd798601be690a29 / |
(+) = 0xefdaadb00000000 \
H(0x80c2) = 0xcabd8974bbee8d5 \ | |
(+) = 0x489d16380ef0000 / |
H(0xa1db) = 0x7ddf8cc3530172b / |
(+) = 0
H(0x6592) = 0x348a96fd685dcba \ |
(+) = 0x357120e8ffb8000 \ |
H(0x76b7) = 0x00e689eb975a346 / | |
(+) = 0x102552500000000 /
H(0x74a6) = 0xacccc4ad2d06bcd \ |
(+) = 0xdab431670048000 /
H(0xe259) = 0x2de76cb9d341433 /
| Algorithm | n | k | memory | solution size | verification 1 | CPU perf. 2 | GPU perf. 3 |
|---|---|---|---|---|---|---|---|
| Equi-X | 60 | 3 | 1.8 MiB | 16 bytes | ~50 μs | 2400 Sol/s | ? |
| Zcash | 200 | 9 | 144 MiB | 1344 bytes | >150 μs | 30 Sol/s | ~400 Sol/s 4 |
| BTG | 144 | 5 | 2.5 GiB | 100 bytes | ~10 μs | 1 Sol/s | ~45 Sol/s 5 |
- Using AMD Ryzen 1700 with 1 thread.
- Using AMD Ryzen 1700 with 16 threads.
- Using NVIDIA GTX 1660 Ti.
- Estimated from http://www.zcashbenchmarks.info/ (GTX 1070)
- Estimated from https://miniz.ch/features/
git clone --recursive https://github.com/tevador/equix.git
cd equix
mkdir build
cd build
cmake ..
make
./equix-tests
./equix-bench --help
See devlog.md
You can support the development of Equi-X by sending XMR to this address:
85GkKXSD8EQ22EMC2ZKF64S6L6Lcm8Gr23VbAKB1zg6FUW81sUEmrvvRPoM3GCpUZSC9azCLdeityW2N3CVsV4CAC3p1evV