Auto-scale MAX_MEMORY_ROWS and CACHE_SIZE settings

h2/src/docsrc/help/help.csv

@@ -1057,7 +1057,8 @@ SET AUTOCOMMIT OFF
 SET CACHE_SIZE int
 ","
 Sets the size of the cache in KB (each KB being 1024 bytes) for the current database.
-The default value is = 65536 * available_RAM_in_G, i.e. 64 MB per G. The value is rounded to the next higher power of two.
+The default is 65536 per available GB of RAM, i.e. 64 MB per GB.
+The value is rounded to the next higher power of two.
 Depending on the virtual machine, the actual memory required may be higher.
 
 This setting is persistent and affects all connections as there is only one cache per database.
@@ -1359,7 +1360,7 @@ SET MAX_MEMORY_ROWS int
 ","
 The maximum number of rows in a result set that are kept in-memory. If more rows
 are read, then the rows are buffered to disk.
-The default value is 40000 per G of available RAM.
+The default is 40000 per GB of available RAM.
 
 Admin rights are required to execute this command, as it affects all connections.
 This command commits an open transaction.

h2/src/docsrc/html/changelog.html

@@ -17,9 +17,10 @@ Change Log
 <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
-<ul><li>Cchange default value of PAGE_SIZE from 2048 to 4096 to more closely match most filesystems block size.
+<ul><li>Change default value of PAGE_SIZE from 2048 to 4096 to more closely match most filesystems block size 
+    (PageStore only; the MVStore already used 4096).
 </li><li>Auto-scale MAX_MEMORY_ROWS and CACHE_SIZE settings by the amount of available RAM. Gives a better
-out of box experience for people with more powerful machines.
+    out of box experience for people with more powerful machines.
 </li></ul>
 
 <h2>Version 1.4.180 Beta (2014-07-13)</h2>

h2/src/main/org/h2/engine/SysProperties.java

@@ -254,7 +254,7 @@ public class SysProperties {
             Utils.getProperty("h2.maxReconnect", 3);
 
     /**
-     * System property <code>h2.maxMemoryRows</code> (default: 40000 per G of available RAM).<br />
+     * System property <code>h2.maxMemoryRows</code> (default: 40000 per GB of available RAM).<br />
      * The default maximum number of rows to be kept in memory in a result set.
      */
     public static final int MAX_MEMORY_ROWS =
@@ -561,21 +561,17 @@ public class SysProperties {
             // we are limited by an -XmX parameter
             return (int) (defaultValue * maxMemory / (1024 * 1024 * 1024));
         }
-        OperatingSystemMXBean mxBean = ManagementFactory
-                .getOperatingSystemMXBean();
         try {
+            OperatingSystemMXBean mxBean = ManagementFactory
+                    .getOperatingSystemMXBean();
             // this method is only available on the class com.sun.management.OperatingSystemMXBean, which mxBean
             // is an instance of under the Oracle JDK, but it is not present on Android and other JDK's
-            Method method = mxBean.getClass().getMethod("getTotalPhysicalMemorySize");
+            Method method = Class.forName(
+                    "com.sun.management.OperatingSystemMXBean").
+                    getMethod("getTotalPhysicalMemorySize");
             long physicalMemorySize = ((Number) method.invoke(mxBean)).longValue();            
             return (int) (defaultValue * physicalMemorySize / (1024 * 1024 * 1024));
-        } catch (NoSuchMethodException e) {
-            // ignore
-        } catch (IllegalArgumentException e) {
-            // ignore
-        } catch (IllegalAccessException e) {
-            // ignore
-        } catch (InvocationTargetException e) {
+        } catch (Exception e) {
             // ignore
         }
         return defaultValue;