Commonalize the cache config and change default to disable cache

examples/config/_common/common.runtime.properties

@@ -14,6 +14,10 @@ druid.metadata.storage.connector.password=diurd
 druid.storage.type=local
 druid.storage.storage.storageDirectory=/tmp/druid/localStorage
 
+# Cache (we use a simple 10mb heap-based local cache on the broker)
+druid.cache.type=local
+druid.cache.sizeInBytes=10000000
+
 # Indexing service discovery
 druid.selectors.indexing.serviceName=overlord
 

examples/config/broker/runtime.properties

@@ -1,6 +1,9 @@
 druid.host=localhost
-druid.service=broker
 druid.port=8080
+druid.service=broker
+
+druid.broker.cache.useCache=true
+druid.broker.cache.populateCache=true
 
 # Bump these up only for faster nested groupBy
 druid.processing.buffer.sizeBytes=100000000

examples/config/coordinator/runtime.properties

@@ -1,5 +1,7 @@
 druid.host=localhost
-druid.service=coordinator
 druid.port=8082
+druid.service=coordinator
 
+# The coordinator begins assignment operations after the start delay.
+# We override the default here to start things up faster for examples.
 druid.coordinator.startDelay=PT70s

examples/config/historical/runtime.properties

@@ -1,8 +1,9 @@
 druid.host=localhost
-druid.service=historical
 druid.port=8081
+druid.service=historical
 
-# Change these to make Druid faster
+# We can only 1 scan segment in parallel with these configs.
+# Our intermediate buffer is also very small so longer topNs will be slow.
 druid.processing.buffer.sizeBytes=100000000
 druid.processing.numThreads=1
 

examples/config/overlord/runtime.properties

@@ -2,6 +2,7 @@ druid.host=localhost
 druid.port=8080
 druid.service=overlord
 
+# Run the overlord in local mode with a single peon to execute tasks
 druid.indexer.queue.startDelay=PT0M
 druid.indexer.runner.javaOpts="-server -Xmx256m"
 druid.indexer.fork.property.druid.processing.numThreads=1

examples/config/realtime/runtime.properties

@@ -1,10 +1,12 @@
 druid.host=localhost
-druid.service=realtime
 druid.port=8083
+druid.service=realtime
 
-# Change this config to metadata to hand off to the rest of the Druid cluster
+# Change this config to 'metadata' to hand off to the rest of the Druid cluster
 druid.publish.type=noop
 
+# We can only 1 scan segment in parallel with these configs.
+# Our intermediate buffer is also very small so longer topNs will be slow.
 druid.processing.buffer.sizeBytes=100000000
 druid.processing.numThreads=1
 

server/src/main/java/io/druid/client/cache/CacheConfig.java

@@ -31,10 +31,10 @@ public class CacheConfig
   public static final String POPULATE_CACHE = "populateCache";
 
   @JsonProperty
-  private boolean useCache = true;
+  private boolean useCache = false;
 
   @JsonProperty
-  private boolean populateCache = true;
+  private boolean populateCache = false;
 
   @JsonProperty
   private List<String> unCacheable = Arrays.asList(Query.GROUP_BY, Query.SELECT);

services/src/main/java/io/druid/cli/CliBroker.java

@@ -90,7 +90,7 @@ public class CliBroker extends ServerRunnable
             binder.bind(TimelineServerView.class).to(BrokerServerView.class).in(LazySingleton.class);
 
             binder.bind(Cache.class).toProvider(CacheProvider.class).in(ManageLifecycle.class);
-            JsonConfigProvider.bind(binder, "druid.broker.cache", CacheProvider.class);
+            JsonConfigProvider.bind(binder, "druid.cache", CacheProvider.class);
             JsonConfigProvider.bind(binder, "druid.broker.cache", CacheConfig.class);
             JsonConfigProvider.bind(binder, "druid.broker.select", TierSelectorStrategy.class);
             JsonConfigProvider.bind(binder, "druid.broker.select.tier.custom", CustomTierSelectorStrategyConfig.class);

services/src/main/java/io/druid/cli/CliHistorical.java

@@ -88,7 +88,7 @@ public class CliHistorical extends ServerRunnable
             LifecycleModule.register(binder, ZkCoordinator.class);            
 
             binder.bind(Cache.class).toProvider(CacheProvider.class).in(ManageLifecycle.class);
-            JsonConfigProvider.bind(binder, "druid.historical.cache", CacheProvider.class);
+            JsonConfigProvider.bind(binder, "druid.cache", CacheProvider.class);
             JsonConfigProvider.bind(binder, "druid.historical.cache", CacheConfig.class);
             MetricsModule.register(binder, CacheMonitor.class);
           }