Jug allows you to write code that is broken up into tasks and run different tasks on different processors.
It uses the filesystem to communicate between processes and works correctly over NFS, so you can coordinate processes on different machines.
Jug is a pure Python implementation and should work on any platform.
Python versions 3.5 and above are supported.
Website: http://luispedro.org/software/jug
Documentation: https://jug.readthedocs.org/
Mailing List: https://groups.google.com/group/jug-users
"I've been using jug with great success to distribute the running of a reasonably large set of parameter combinations" - Andreas Longva
You can install Jug with pip:
pip install Jug
or use, if you are using conda, you can install jug from conda-forge using the following commands:
conda config --add channels conda-forge conda install jug
If you use Jug to generate results for a scientific publication, please cite
Coelho, L.P., (2017). Jug: Software for Parallel Reproducible Computation in Python. Journal of Open Research Software. 5(1), p.30.
Here is a one minute example. Save the following to a file called primes.py
(if you have installed jug, you can obtain a slightly longer version of this
example by running jug demo
on the command line):
from jug import TaskGenerator from time import sleep @TaskGenerator def is_prime(n): sleep(1.) for j in range(2,n-1): if (n % j) == 0: return False return True primes100 = [is_prime(n) for n in range(2,101)]
This is a brute-force way to find all the prime numbers up to 100. Of course,
this is only for didactical purposes, normally you would use a better method.
Similarly, the sleep
function is so that it does not run too fast. Still,
it illustrates the basic functionality of Jug for embarassingly parallel
problems.
Type jug status primes.py
to get:
Task name Waiting Ready Finished Running ---------------------------------------------------------------------- primes.is_prime 0 99 0 0 ...................................................................... Total: 0 99 0 0
This tells you that you have 99 tasks called primes.is_prime
ready to run.
So run jug execute primes.py &
. You can even run multiple instances in the
background (if you have multiple cores, for example). After starting 4
instances and waiting a few seconds, you can check the status again (with jug
status primes.py
):
Task name Waiting Ready Finished Running ---------------------------------------------------------------------- primes.is_prime 0 63 32 4 ...................................................................... Total: 0 63 32 4
Now you have 32 tasks finished, 4 running, and 63 still ready. Eventually, they
will all finish and you can inspect the results with jug shell primes.py
.
This will give you an ipython
shell. The primes100 variable is available,
but it is an ugly list of jug.Task objects. To get the actual value, you call
the value function:
In [1]: primes100 = value(primes100) In [2]: primes100[:10] Out[2]: [True, True, False, True, False, True, False, False, False, True]
Version 2.1.1 (18 March 2021)
- Include requirements files in distribution
Version 2.1.0 (18 March 2021)
- Improvements to webstatus (by Robert Denham)
- Removed Python 2.7 support
- Fix output encoding for Python 3.8
- Fix bug mixing
mapreduce()
&status --cache
- Make block_access (used in
mapreduce()
) much faster (20x) - Fix important redis bug
- More precise output in
cleanup
command
Version 2.0.2 (Thu Jun 11 2020)
- Fix command line argument parsing
Version 2.0.1 (Thu Jun 11 2020)
- Fix handling of
JUG_EXIT_IF_FILE_EXISTS
environmental variable - Fix passing an argument to
jug.main()
function - Extend
--pdb
to exceptions raised while importing the jugfile (issue #79)
version 2.0.0 (Fri Feb 21 2020)
- jug.backend.base_store has 1 new method 'listlocks'
- jug.backend.base_lock has 2 new methods 'fail' and 'is_failed'
- Add 'jug execute --keep-failed' to preserve locks on failing tasks.
- Add 'jug cleanup --failed-only' to remove locks from failed tasks
- 'jug status' and 'jug graph' now display failed tasks
- Check environmental exit variables by default (suggested by Renato Alves, issue #66)
- Fix 'jug sleep-until' in the presence of barrier() (issue #71)
For older version see ChangeLog
file or the full history.