~xjobs/
home of xjobs utility

Description

xjobs reads job descriptions line by line and executes them in parallel. It limits the number of parallel executing jobs and starts new jobs when jobs finish. Therefore, it combines the arguments from every input line with the utility and arguments given on the command line. If no utility is given as an argument to xjobs, then the first argument on every job line will be used as utility. To execute utility xjobs searches the directories given in the PATH environment variable and uses the first file found in these directories.

xjobs is most useful on multi-processor/core machines when one needs to execute several time consuming command several that could possibly be run in parallel. With xjobs this can be achieved easily, and it is possible to limit the load of the machine to a useful value. It works similar to xargs, but starts several processes simultaneously and gives only one line of arguments to each utility call.

Technology/Features

xjobs is written in C and uses the POSIX API. There is nothing special about it, but if one searches a small and useful example for lex integration, its source code may be worth a look.

Current status

xjobs is stable. If you encounter a bug or need an enhancement, please feel free to contact me.

Comment on GNU xargs vs. xjobs

Yes, GNU's xargs has an option -P that allow parallelizing jobs. But you must tell xargs how many arguments to pass to each job, as it doesn't make a difference between a space and a newline charakter. In consequence each job issued by xargs must have the same number of arguments, whereas xjobs can handle different jobs with different commands and different number of arguments.

Additionally, xjobs support I/O redirection, which makes some applications possible that cannot be done with GNU's xargs. xjobs also determines the number of processors automatically, whereas xargs must be told how many processes to start. Finally, non-GNU xargs (e.g. Solaris' and DEC/Compaq/HP Alpha's) don't have the option -P. Try to do the following with GNU's xargs with some files having blanks in their name:

If you aren't convinced yet, just compare the output of unziping multiple zip files in parallel with xjobs and GNU xargs. xjobs won't intermix the output of unzip like xargs. Instead it will present the output of each unzip separated clearly from the other jobs.

Download

Binaries

OpenCSW Packages for Solaris

Sources

The tar/gzip files have been generated with Schilly's star for maximum portability. There are sometimes situations where GNU tar might fail to handle these packages. If you encounter any problems untaring the files, please upgrade to a more recent version of GNU tar (1.15.1 is know to work fine). I am currently considering, how to generate the packages in the future.

Version 20100311 (current release)
Version 20100203
Version 20091012
Version 20080824
Version 20080520
Version 20080322
Version 20080213
Version 20080122
Version 20071122
Version 20070923
Version 20070915
Version 20061008
Version 20060807
Version 20060731
Version 20060726
Version 20060720
Version 20060709
Version 20060413 Take a look at my blog entry, concerning this release.
Version 20060412
Version 20060411
Version 20060410
Version 20060409
Version 20060408 (initial release)

LICENSE:

GNU GPL 2

ARCHITECTURES:

This software has been successfully tested under the following operatingsystems:
Thomas Maier-Komor