Minor performance tuning to avoid excessive connection attempts of downed databases.

hikaricp-java6/src/main/java/com/zaxxer/hikari/pool/HikariPool.java

@@ -296,7 +296,7 @@ public final class HikariPool implements HikariPoolMBean, IBagStateListener
             while (!isShutdown && totalConnections.get() < maxPoolSize && (minIdle == 0 || getIdleConnections() < minIdle)) {
                if (!addConnection()) {
                   quietlySleep(sleepBackoff);
-                  sleepBackoff = Math.min(1000L, (long) ((double) sleepBackoff * 1.5));
+                  sleepBackoff = Math.min(connectionTimeout / 2, (long) ((double) sleepBackoff * 1.5));
                   continue;
                }
 

hikaricp-java6/src/main/java/com/zaxxer/hikari/util/PoolUtilities.java

@@ -128,9 +128,9 @@ public final class PoolUtilities
          threadFactory = new DefaultThreadFactory(threadName, true);
       }
 
-      int processors = Math.max(1, Runtime.getRuntime().availableProcessors() / 2);
+      int processors = Math.max(1, Runtime.getRuntime().availableProcessors() / 4);
       LinkedBlockingQueue<Runnable> queue = new LinkedBlockingQueue<Runnable>(queueSize);
-      ThreadPoolExecutor executor = new ThreadPoolExecutor(processors, processors, 2, TimeUnit.SECONDS, queue, threadFactory,
+      ThreadPoolExecutor executor = new ThreadPoolExecutor(processors, processors, 5, TimeUnit.SECONDS, queue, threadFactory,
                                                            new ThreadPoolExecutor.DiscardPolicy());
       executor.allowCoreThreadTimeOut(true);
       return executor;

hikaricp/src/main/java/com/zaxxer/hikari/pool/HikariPool.java

@@ -293,7 +293,7 @@ public final class HikariPool implements HikariPoolMBean, IBagStateListener
          while (!isShutdown && totalConnections.get() < maxPoolSize && (minIdle == 0 || getIdleConnections() < minIdle)) {
             if (!addConnection()) {
                quietlySleep(sleepBackoff);
-               sleepBackoff = Math.min(1000L, (long) ((double) sleepBackoff * 1.5));
+               sleepBackoff = Math.min(connectionTimeout / 2, (long) ((double) sleepBackoff * 1.5));
                continue;
             }
 

hikaricp/src/main/java/com/zaxxer/hikari/util/PoolUtilities.java

@@ -110,9 +110,9 @@ public final class PoolUtilities
          threadFactory = new DefaultThreadFactory(threadName, true);
       }
 
-      int processors = Math.max(1, Runtime.getRuntime().availableProcessors() / 2);
+      int processors = Math.max(1, Runtime.getRuntime().availableProcessors() / 4);
       LinkedBlockingQueue<Runnable> queue = new LinkedBlockingQueue<Runnable>(queueSize);
-      ThreadPoolExecutor executor = new ThreadPoolExecutor(processors, processors, 2, TimeUnit.SECONDS, queue, threadFactory,
+      ThreadPoolExecutor executor = new ThreadPoolExecutor(processors, processors, 5, TimeUnit.SECONDS, queue, threadFactory,
                                                            new ThreadPoolExecutor.DiscardPolicy());
       executor.allowCoreThreadTimeOut(true);
       return executor;