sysadmin.adoc: add more ZFS tips

diff --git a/sysadmin.adoc b/sysadmin.adoc
index 2ffe1507e42aaaa4903f33ec5eba80d7619b40e8..a543e7e39fabc980be7523cbf977ca322f735d74 100644 (file)
--- a/sysadmin.adoc
+++ b/sysadmin.adoc
@@ -276,9 +276,20 @@ If you have more than one disk, you can also use ZFS as file system.
 ZFS supports several software RAID levels, so this is specially useful
 if you do not have a hardware RAID controller.
 
 ZFS supports several software RAID levels, so this is specially useful
 if you do not have a hardware RAID controller.
 

-TIP: ZFS uses a lot of memory, so it is best to add additional 8-16GB RAM
+.ZFS Performance Tips
+****
+ZFS uses a lot of memory, so it is best to add additional 8-16GB RAM

 if you want to use ZFS.
 
 if you want to use ZFS.
 

+.Use fast SSD as write cache
+
+ZFS provides the feature to use a fast SSD drive as write cache. The
+write cache is called the ZFS Intent Log (ZIL). You can add that after
+installation using the following command:
+
+ zpool add <pool-name> log </dev/path_to_fast_ssd>
+****
+

 The next pages just asks for basic configuration options like time
 zone and keyboard layout. You also need to specify your email address
 and select a superuser password.
 The next pages just asks for basic configuration options like time
 zone and keyboard layout. You also need to specify your email address
 and select a superuser password.