From f9b92420fbf2107b050d41f3cb304ac285ed3be0 Mon Sep 17 00:00:00 2001
From: Eliot Horowitz <eliot@10gen.com>
Date: Fri, 2 Nov 2012 15:42:17 -0400
Subject: [PATCH] SERVER-7543 - don't over allocate extents, just round

---
 jstests/capped_server7543.js | 11 +++++++++++
 src/mongo/db/pdfile.cpp      |  4 +++-
 2 files changed, 14 insertions(+), 1 deletion(-)
 create mode 100644 jstests/capped_server7543.js

diff --git a/jstests/capped_server7543.js b/jstests/capped_server7543.js
new file mode 100644
index 0000000000000..514cd7964b299
--- /dev/null
+++ b/jstests/capped_server7543.js
@@ -0,0 +1,11 @@
+
+mydb = db.getSisterDB( "capped_server7543" );
+mydb.dropDatabase();
+
+mydb.createCollection( "foo" ,  { capped : true , size : 12288 } );
+
+assert.eq( 12288, mydb.foo.stats().storageSize );
+assert.eq( 1, mydb.foo.validate(true).extentCount );
+
+mydb.dropDatabase();
+
diff --git a/src/mongo/db/pdfile.cpp b/src/mongo/db/pdfile.cpp
index 34bc17999da19..dd8f4896cf909 100644
--- a/src/mongo/db/pdfile.cpp
+++ b/src/mongo/db/pdfile.cpp
@@ -242,8 +242,10 @@ namespace mongo {
             BSONElement e = options.getField("size");
             if ( e.isNumber() ) {
                 size = e.numberLong();
-                size += 256;
+                size += 0xff;
                 size &= 0xffffffffffffff00LL;
+                if ( size < Extent::minSize() )
+                    size = Extent::minSize();
             }
         }