Improve grammar and spelling in durability discussion.

diff --git a/doc/src/sgml/perform.sgml b/doc/src/sgml/perform.sgml
index 1bec5b1f7e5779d4121a90924aad82742b4f54eb..20cb79046827b3a661765268e12fbaf0185942d5 100644 (file)
--- a/doc/src/sgml/perform.sgml
+++ b/doc/src/sgml/perform.sgml
@@ -1118,9 +1118,10 @@ SELECT * FROM x, y, a, b, c WHERE something AND somethingelse;
     so if your site does not require such a guarantee,
     PostgreSQL can be configured to run
     much faster.  The following are configuration changes you can make
-    to improve performance in such cases;  they do not invalidate
-    commit guarantees related to database crashes, only abrupt operating
-    system stoppage, except as mentioned below:
+    to improve performance in such cases.  Except as noted below, durability
+    is still guaranteed in case of a crash of the database software;
+    only abrupt operating system stoppage creates a risk of data loss
+    or corruption when these settings are used.
 
     
      
@@ -1159,8 +1160,8 @@ SELECT * FROM x, y, a, b, c WHERE something AND somethingelse;
       
        Turn off ;  there might be no
        need to write the WAL to disk on every
-       commit.  This does enable possible tranaction loss in case of
-       a database crash.
+       commit.  This setting does risk transaction loss (though not data
+       corruption) in case of a crash of the database alone.