From: Eric Blake <eblake@redhat.com>
Date: Wed, 30 Oct 2019 15:56:53 +0000 (+0100)
Subject: 8300: Graphics showing polling.
X-Git-Url: http://git.annexia.org/?a=commitdiff_plain;h=0694a3cc0ca53edc35a4f5476ad659c8d12fa81c;p=libguestfs-talks.git

8300: Graphics showing polling.
---

diff --git a/2019-kvm-forum/8000-graphics.odp b/2019-kvm-forum/8000-graphics.odp
index 425f996..fc014ca 100644
Binary files a/2019-kvm-forum/8000-graphics.odp and b/2019-kvm-forum/8000-graphics.odp differ
diff --git a/2019-kvm-forum/8300-notify.png b/2019-kvm-forum/8300-notify.png
new file mode 100644
index 0000000..609988a
Binary files /dev/null and b/2019-kvm-forum/8300-notify.png differ
diff --git a/2019-kvm-forum/8300-poll.png b/2019-kvm-forum/8300-poll.png
new file mode 100644
index 0000000..04bec0c
Binary files /dev/null and b/2019-kvm-forum/8300-poll.png differ
diff --git a/2019-kvm-forum/8300-tradeoff-poll-v-notify.html b/2019-kvm-forum/8300-tradeoff-poll-v-notify.html
index 8e9f729..3ed0051 100644
--- a/2019-kvm-forum/8300-tradeoff-poll-v-notify.html
+++ b/2019-kvm-forum/8300-tradeoff-poll-v-notify.html
@@ -5,22 +5,24 @@
 <h1>Tradeoff: poll or notify</h1>
 
 <p>
-  Filler - need to demonstrate:
+  Polling:
+  <ul>
+    <li>Server cannot report size unless client asks
+    <li>Each server reply sets <code>NBD_REPLY_DONE</code> flag bit
+    <li>Client must ask in a loop when polling for a change from the
+      server
+  </ul>
+<p>
+  <img src="8300-poll.png"/>
 
 <p>
-  polling (server cannot tell client about async changes unless client
-  polls):
-  <br>client: NBD_CMD_RESIZE(0)
-  <br>server: NBD_REPLY_TYPE_RESIZE response, including NBD_REPLY_DONE
-  <br>do stuff
-  <br>client: NBD_CMD_RESIZE(0)
-  <br>server: NBD_REPLY_TYPE_RESIZE response, including NBD_REPLY_DONE
+  Notify:
+  <ul>
+    <li>Client uses <code>NBD_CMD_FLAG_RESIZE_NOTIFY</code> to
+      request an open-ended command
+    <li>Server replies with <code>NBD_REPLY_DONE</code> flag clear
+      whenever it has a new size to report
+  </ul>
 <p>
-  notify (client registers open-ended command to allow multiple async
-  server responses as needed):
-  <br>client: NBD_CMD_RESIZE(NBD_CMD_FLAG_NOTIFY)
-  <br>do stuff
-  <br>server: NBD_REPLY_TYPE_RESIZE response, excluding NBD_REPLY_DONE
-  <br>do stuff
-  <br>server: NBD_REPLY_TYPE_RESIZE response, excluding NBD_REPLY_DONE
+  <img src="8300-notify.png"/>
 </p>