Add shared downloads and sstate cache
reuse downloaded sources and sstate to speed up builds
Change-Id: I198a4ba37429ae0dbb5021491eb7421efacd72d3
Signed-off-by: Hariharan Rangasamy <hariharanr@ami.com>
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/development/dev-environment.md b/development/dev-environment.md
index c5b9799..b1697b6 100644
--- a/development/dev-environment.md
+++ b/development/dev-environment.md
@@ -223,3 +223,25 @@
- after that the all the a TAP network interface is added, and protocol like
ssh, scp, http work well.
+
+## Sharing Downloads and Build Cache
+
+BitBake caches both fetched sources (DL_DIR) and reusable build outputs
+(SSTATE_DIR). Point multiple builds at shared directories to avoid
+re-downloading and re-building, saving time and disk.
+
+1. Create shared cache directories once:
+
+ ```bash
+ mkdir -p "${XDG_CACHE_HOME}/data/bitbake.downloads" "${XDG_CACHE_HOME}/data/bitbake.sstate"
+ ```
+
+2. Add to build/conf/local.conf:
+
+ ```bash
+ DL_DIR = "${XDG_CACHE_HOME}/data/bitbake.downloads"
+ SSTATE_DIR = "${XDG_CACHE_HOME}/data/bitbake.sstate"
+ ```
+
+This makes every build reuse what was already downloaded and built, so you use
+less disk and finish faster.