  The way practitioners perform maintenance tasks in practice is little known
by researchers. In turn, practitioners are not always up to date with the
proposals provided by the research community. This work investigates the gap
between software maintenance techniques proposed by the research community and
the software maintenance practice. We carried out a survey with 112
practitioners from 92 companies and 12 countries. We concentrate on analyzing
if and how practitioners understand and apply the following subjects: bad
smells, refactoring, software metrics, and change impact analysis. This study
shows that there is a large gap between research approaches and industry
practice in those subjects, especially in change impact analysis and software
metrics.
