Introduction to HTCondor
========================

:index:`user manual<single: user manual; HTCondor>` :index:`user manual`

The HTCondor software system is developed by the Center for High Throughput
Computing at the University of Wisconsin-Madison (UW-Madison), and was first
installed as a production system in the UW-Madison Computer Sciences department
in the 1990s. HTCondor pools have since served as a major source of computing
cycles to thousands of campuses, labs, organizations and commercial entities.
For many, it has revolutionized the role computing plays in their research.
Increasing computing throughput by several orders of magnitude may not merely
deliver the same results faster, but may enable qualitatively different avenues
of research.

HTCondor is a specialized batch system :index:`batch system` for managing
compute-intensive jobs. HTCondor provides a queuing mechanism, scheduling
policy, priority scheme, and resource classifications. Users submit their
compute jobs to HTCondor, HTCondor puts the jobs in a queue, runs them, and
then informs the user as to the result.

Batch systems normally operate only with dedicated machines. Often termed
worker nodes, these dedicated machines are typically owned by one group and
dedicated to the sole purpose of running compute jobs. HTCondor can schedule
jobs on dedicated machines. But unlike traditional batch systems, HTCondor is
also designed to run jobs on machines shared and used by other systems or
people. By running on these shared resources, HTCondor can effectively harness
all machines throughout a campus. This is important because often an
organization has more latent, idle computers than any single department or
group otherwise has access to.
