Merge pull request #29 from YoeDistro/cbrake/master

start documentation/settings for enabling systemd
YoeDistro · Oct 9, 2018 · 69bb294 · 69bb294
2 parents eeb0e41 + 6c0989a
commit 69bb294
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diff --git a/conf/local.conf b/conf/local.conf
@@ -46,3 +46,9 @@ PACKAGE_FEED_URIS ??= "http://<FEEDSERVER>"
 
 # Enable serial console on Raspberry PI systems
 ENABLE_UART = "1"
+
+# Uncomment the following to enable systemd
+#DISTRO_FEATURES_append = " systemd"
+#VIRTUAL-RUNTIME_init_manager = "systemd"
+#DISTRO_FEATURES_BACKFILL_CONSIDERED = "sysvinit"
+#VIRTUAL-RUNTIME_initscripts = ""
diff --git a/docs/init-system.md b/docs/init-system.md
@@ -0,0 +1,26 @@
+# Init System
+
+SysVinit and Systemd are common init systems. SysVinit is the default, but Systemd can
+be enabled be adding the following to local.conf:
+
+```
+DISTRO_FEATURES_append = " systemd"
+VIRTUAL-RUNTIME_init_manager = "systemd"
+DISTRO_FEATURES_BACKFILL_CONSIDERED = "sysvinit"
+VIRTUAL-RUNTIME_initscripts = ""
+```
+
+Systemd takes considerably more space than SysVinit. With a rPI2 build, the following
+are the rootfs sizes for core-image-minimal:
+
+* SysVinit
+  * space used in ext4 filesystem on running system using df: 4.7MB
+  * adding sizes of files in image from buildhistory: 4.3MB
+  * number of files in image: 696
+* Systemd
+  * space used in ext4 filesystem on running system using df: 33.2MB
+  * adding sizes of files in image from buildhistory: 22MB
+  * number of files in image: 1,806
+
+There is a significant size cost with systemd, so in some cases it may make sense to
+use sysvinit if image size is a priority.