From ca85107b9ad5358573052b88e98665c7110288c2 Mon Sep 17 00:00:00 2001 From: Scott Rifenbark Date: Mon, 3 Oct 2016 10:02:05 -0700 Subject: [PATCH] ref-manual: Updated build/tmp/cache/ reference section Fixes [YOCTO #10356] Expanded the general description of this directory. (From yocto-docs rev: df71fe472f9d5cb5f809706ec4218952a49d31d3) Signed-off-by: Scott Rifenbark Signed-off-by: Richard Purdie --- documentation/ref-manual/ref-structure.xml | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/documentation/ref-manual/ref-structure.xml b/documentation/ref-manual/ref-structure.xml index 6912d3f6b2..541a47e556 100644 --- a/documentation/ref-manual/ref-structure.xml +++ b/documentation/ref-manual/ref-structure.xml @@ -660,9 +660,21 @@ <filename>build/tmp/cache/</filename> - When BitBake parses the metadata, it creates a cache file of the result that can - be used when subsequently running commands. - BitBake stores these results here on a per-machine basis. + When BitBake parses the metadata (recipes and configuration files), + it caches the results in build/tmp/cache/ + to speed up future builds. + The results are stored on a per-machine basis. + + + + During subsequent builds, BitBake checks each recipe (together + with, for example, any files included or appended to it) to see + if they have been modified. + Changes can be detected, for example, through file modification + time (mtime) changes and hashing of file contents. + If no changes to the file are detected, then the parsed result + stored in the cache is reused. + If the file has changed, it is reparsed.