improve documentation and defaults

[ganeti-extstorage-zfs] / defaults.sh

diff --git a/defaults.sh b/defaults.sh
index 7c44b7e..28c3173 100644 (file)
--- a/defaults.sh
+++ b/defaults.sh
@@ -1,6 +1,9 @@
 
-# pool and path where to create block devices
+# zfs pool and file system (existing) where to create block devices
 test -z "$EXTP_BLOCK" && EXTP_BLOCK=tmp500g/block
 
-# parameters for zfs create
+# parameters for zfs create, by default
+# -s   sparse
+# -b 4k        block size sutable for ext4 filesystem which ganeti uses
+# lz4  compression with low cpu operhead which always helps
 test -z "$EXTP_VOL_PARAM" && EXTP_VOL_PARAM="-s -b 4k -o compression=lz4"