X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=Filesystems.m4;h=1a77ef882e9ebb6c412380add1c2787acc32a291;hb=refs%2Fheads%2Fpu;hp=24bff397fe5106b667bc89307236405c01387562;hpb=a7c4b1241cc0ce84713a63b622cb4b3cb26cea72;p=aple.git

diff --git a/Filesystems.m4 b/Filesystems.m4
index 24bff39..7750dab 100644
--- a/Filesystems.m4
+++ b/Filesystems.m4
@@ -829,6 +829,27 @@ it's best to make the LV slightly larger than necessary and then
 enlarge the filesystem to the maximal possible size by running
 <code>resize2fs(8)</code> without specifying the new size. </p>
 
+SUBSECTION(«Fast Commits»)
+
+<p>
+
+Optimization introduced in 2020 (Linux-5.10).
+
+activated at mkfs time
+
+light-weight journaling method
+
+Idea: parts of the metadata written to the log can instead be derived
+from the inode. Leads to more compact format.
+
+Implementation: additional journal for fast commits, i.e., for those
+operations that can be optimized. Contains changes at the *file* level
+
+<li> Check <code>/proc/fs/ext4/dev/fc_info</code> to see whether fast
+commits are supported in the runing kernel. </li>
+
+</p>
+
 EXERCISES()
 
 <ul>
@@ -1385,7 +1406,7 @@ silly renames: An NFS4.1 server knows when it its safe to unlink a
 file and communicates this information to the client. </p>
 
 <p> The file handle which an nfs client received through some earlier
-rpc can become invalid at any time due to operations on a different
+rpc can become invalid at any time due to operations on different
 hosts. This happens, for example, if the file was deleted on the server
 or on a different nfs client, or when the directory that contains
 the file is no longer exported by the server due to a configuration