Skip to content
An example of using rust's `std::sync::mpsc` with multiple threads of execution to find a hash of given difficulty.
Branch: master
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.
src return when solution is found, instead of only breaking from the loop Nov 2, 2017


An example of using std::sync::mpsc with multiple threads of execution. The computation-heavy algorithm used in this example is a basic implementation of an idea behind cryptocurrencies mining process (so-called "Proof of Work", or solving the cryptographic problem).

About the cryptographic algorithm

An example: given a number 42 (the "constant base"), find a number x to multiply it by, so that the result of this multiplication hashed by SHA-256 will produce a hash string ending with 000000.

The actual solution is 3,305,951, which - while multiplied by 42 gives 138,849,942, producing a 2a44903ffc6affe69d514ffe47721cc3a6475cbb43b37538686f2c5b46000000 hash.

About std::sync::mpsc

This example uses std::sync::mpsc as a channel of communication between four worker threads and the main thread. Each worker thread analyses unique numbers (by starting the iterations at different "points" and having constant step). For more info, see the large comment inside src/'s main() function.


This example uses unstable feature - the step_by method from std::iter::Iterator's implementation for std::ops::Range. This is why #![feature(iterator_step_by)] attribute is present at the top of src/ For that reason, this project will currently compile with nightly only!

To compile with nightly:

  1. cd to project's root,
  2. run rustup override set nightly

For maximum performance, instead of running with bare cargo run I recommend to add the --relase flag:

  1. cd to project's root,
  2. run cargo run --release and enjoy!

Feel free to experiment - change the value of DIFFICULTY constant in src/ and/or THREADS! Please note that a change by one extra desired character in DIFFICULTY (eg. one more 0) can increase the overall difficulty of the problem dramatically, thus noticeably extending the time needed to find the solution!



You can’t perform that action at this time.