yum-presto is a
yum extension that searches for
deltarpms instead of rpms when these are availables in the repositories. This saves a lot of bandwidth when updating.
A deltarpm is the difference between two rpms. If you have installed foo-1.0 and foo-1.1 is available, yum-presto will download the deltarpm to foo-1.0 => 1.1 instead of downloading the whole foo-1.1.rpm, and will rebuild foo-1.1 package from the foo-1.0 installedone and the downloaded deltarpm.
It is necessary to have repositories with deltarpms enabled. Fedora official repositories offer drpms since Fedora 11, so they are configured to use them out of the box.
/etc/yum/pluginconf.d/presto.conf
# Please go to https://fedorahosted.org/presto for a list of presto-enabled
# repositories
[main]
enabled=1
# This defaults to yum's keepcache option, if not set.
# keepdeltas = false
# This lets you change if the delta is downloaded given it's relative size vs.
# the pkg. Eg. the default:
#
# minimum_percentage = 95
#
# ...means that given a pkg of 100M, a delta of 95M (or less) would be
# downloaded instead but a delta of 96M would be skipped in favour of the pkg.
# Percentage of 0 means never use the delta, percentage of 100 means always
# use it (assuming the delta is never bigger than the pkg).
enabled = 0|1
Enable extension at a general level.
keepdeltas = true|false
Keep a drpms cache. If no value is set, it uses the yum keepcache
directive setting.
minimum_percentage = #integer
Comparison value against the rpm package to make a decision to choose to download the rpm. 100 means it will always use the deltas, 0 means not to use deltas.