This chapter will teach you one technique for speeding up access to an
arch version that contains many revisions:
mainline -------- base-0 patch-1 .... patch-23 patch-24 patch-25 ... patch-42
Suppose that a user (with no local pristine cache) wants to
get proceeds by first getting and unpacking
base-0 revision, then getting each
patch-<N> changeset, in
order, and applying those to the tree.
If the list of changesets that need to be applied is long, or the sum
of their sizes large in comparison to the tree side, then this
get is needlessly inefficient.
One way to speed up
get is by archive caching revisions – storing
"pre-built" copies of some revisions with the archive.
For example, the command:
% tla cacherev -A email@example.com \ hello-world--mainline--0.1--patch-40
will build the
patch-40 revision, package it up as a tar bundle, and
store a copy of that tar bundle in the
patch-40 directory of the
patch-42 will work by first fetching the
cached copy of the
patch-40 revision, then getting and applying the
patch-42: a savings of
Usage Note: At this time, it's left up to you to decide which
revisions to cache and which not. You might decide, for example, to
automatically cache certain revisions from a
cron job or to simply
cache revisions by-hand whenever you notice that
get is too slow.
In the future, we hope to add better support for automatically caching