X-Git-Url: https://git.decadent.org.uk/gitweb/?a=blobdiff_plain;f=index.html;h=68e0fe8758e490ef43e0eff170aae6764ea21ba5;hb=beefb0772ed40f965df983c7d06823dd44338d57;hp=12c844c561d94da49c17153299ec0870902c0eb0;hpb=c8edb32ab191e7e9e3cab0174437a51c680de859;p=kernel-news-talk.git

diff --git a/index.html b/index.html
index 12c844c..68e0fe8 100644
--- a/index.html
+++ b/index.html
@@ -170,27 +170,6 @@
   </ul>
 </div>
 
-<div class="slide">
-  <h1>Lustre filesystem [3.12]</h1>
-  <ul>
-    <li>
-      A distributed filesystem, popular for cluster computing
-      applications
-    </li>
-    <li>
-      Developed out-of-tree since 1999, but now added to Linux staging
-      directory
-    </li>
-    <li>
-      Was included in squeeze but dropped from wheezy as it didn't
-      support Linux 3.2
-    </li>
-    <li>
-      Userland is now missing from Debian
-    </li>
-  </ul>
-</div>
-
 <div class="slide">
   <h1>Network busy-polling [3.11] (1)</h1>
   <p>A conventional network request/response process looks like:</p>
@@ -253,6 +232,27 @@
   </ul>
 </div>
 
+<div class="slide">
+  <h1>Lustre filesystem [3.12]</h1>
+  <ul>
+    <li>
+      A distributed filesystem, popular for cluster computing
+      applications
+    </li>
+    <li>
+      Developed out-of-tree since 1999, but now added to Linux staging
+      directory
+    </li>
+    <li>
+      Was included in squeeze but dropped from wheezy as it didn't
+      support Linux 3.2
+    </li>
+    <li>
+      Userland is now missing from Debian
+    </li>
+  </ul>
+</div>
+
 <div class="slide">
   <h1>Btrfs offline dedupe [3.12]</h1>
   <ul class="incremental">
@@ -284,12 +284,11 @@
       and ebtables
     </li>
     <li>
-      All require a specific kernel module for each type of match
-      and each possible action
+      All limited to single protocol, and need a kernel module for
+      each match type and each action
     </li>
     <li>
-      Userland could only use the four protocol-specific APIs,
-      although the internal netfilter API is more flexible
+      Kernel's internal netfilter API is more flexible
     </li>
     <li>
       nftables exposes more of this flexibility, allowing userland
@@ -299,7 +298,7 @@
       nftables userland tool uses this API and is already packaged
     </li>
     <li>
-      Eventually, the old APIs will be removed and the old userland
+      Eventually, old APIs will be removed and old userland
       tools must be ported to use nftables
     </li>
   </ul>
@@ -353,6 +352,33 @@
   </ul>
 </div>
 
+<div class="slide">
+  <h1>File-private locking [3.15]</h1>
+  <ul class="incremental">
+    <li>
+      POSIX says that closing a file descriptor removes
+      the <em>process</em>'s locks on that file
+    </li>
+    <li>
+      What if process has multiple file descriptors for the same
+      file?  It loses all locks obtained through any descriptor!
+    </li>
+    <li>
+      Multithreaded processes may require serialisation around
+      file open/close to ensure they open each file exactly once
+    </li>
+    <li>
+      Hard and symbolic links can hide that two files are really the
+      same
+    </li>
+    <li>
+      Linux now provides file-private locks, associated with a
+      specific open file and removed when last descriptor for the
+      open file is closed
+    </li>
+  </ul>
+</div>
+
 <div class="slide">
   <h1>Questions?</h1>
 </div>