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Date:      01 Nov 2001 15:09:47 +0100
From:      Dag-Erling Smorgrav <des@ofug.org>
To:        doc@freebsd.org
Cc:        Paul Robinson <paul@akita.co.uk>
Subject:   FAQ addition
Message-ID:  <xzpr8rimvkk.fsf@flood.ping.uio.no>

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Please see attached patch.

DES
-- 
Dag-Erling Smorgrav - des@ofug.org


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Content-Type: text/x-patch
Content-Disposition: attachment; filename=dev-null.diff

Index: doc/en_US.ISO8859-1/books/faq/book.sgml
===================================================================
RCS file: /home/ncvs/doc/en_US.ISO8859-1/books/faq/book.sgml,v
retrieving revision 1.279
diff -u -r1.279 book.sgml
--- doc/en_US.ISO8859-1/books/faq/book.sgml	2001/10/31 23:26:02	1.279
+++ doc/en_US.ISO8859-1/books/faq/book.sgml	2001/11/01 14:08:37
@@ -11563,6 +11563,62 @@
             Please do not reproduce without attribution.</emphasis></para>
         </answer>
       </qandaentry>
+      
+      <qandaentry>
+        <question id="dev-null">
+          <para>Where does data written to <filename>/dev/null</filename>
+	    go?</para>
+        </question>
+        <answer>
+          <para>It goes into a special data sink in the CPU where it
+            is converted to heat which is vented through the heatsink
+            / fan assembly.  This is why CPU cooling is increasingly
+            important; as people get used to faster processors, they
+            become careless with their data and more and more of it
+            ends up in <filename>/dev/null</filename>, overheating
+            their CPUs.  If you delete <filename>/dev/null</filename>
+            (which effectively disables the CPU data sink) your CPU
+            may run cooler but your system will quickly become
+            constipated with all that excess data and start to behave
+            erratically.  If you have a fast network connection you
+            can cool down your CPU by reading data out of /dev/random
+            and sending it off somewhere; however you run the risk of
+            overheating your network connection and / or angering your
+            ISP, as most of the data will end up getting converted to
+            heat by their equipment, but they generally have good
+            cooling, so if you don't overdo it you should be
+            OK.</para>
+
+	  <para><emphasis>Paul Robinson adds:</emphasis</para>
+
+	  <para>There are other methods. As every good sysadmin knows,
+            it is part of standard practise to send data to the screen
+            of interesting variety to keep all the pixies that make up
+            your picture happy. Screen pixies (commonly mis-typed or
+            re-named as 'pixels') are categorised by the type of hat
+            they wear (red, green or blue) and will hide or appear
+            (thereby showing the colour of their hat) whenever they
+            receive a little piece of food. Video cards turn data into
+            pixie-food, and then send them to the pixies - the more
+            expensive the card, the better the food, so the better
+            behaved the pixies are. They also need constant simulation
+            - this is why screen savers exist.</para>
+
+          <para>To take your suggestions further, you could just throw
+            the random data to console, thereby letting the pixies
+            consume it. This causes no heat to be produced at all,
+            keeps the pixies happy and gets rid of your data quite
+            quickly, even if it does make things look a bit messy on
+            your screen.</para>
+
+          <para>Incidentally, as an ex-admin of a large ISP who
+            experienced many problems attempting to maintain a stable
+            temperature in a server room, I would strongly discourage
+            people sending the data they don't want out to the
+            network. The fairies who do the packet switching and
+            routing get annoyed by it as well.</para>
+	</answer>
+      </qandaentry>
     </qandaset>
   </chapter>
 

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