diff --git a/README.md b/README.md
index ff5d4db..892f826 100644
--- a/README.md
+++ b/README.md
@@ -12,7 +12,7 @@ There are a couple of things which seem to be an absolute must and which were mi
 * aggregation: ability to sum similar metrics from several servers
 * blacklisting: ability to omit storing metrics which match a certain pattern. Makes not much sense by itself but is quite handy when you have previous item
 * caching incoming paths: this may really reduce the load on Elasticsearch cluster
-* some minimal set of own metrics (received count, write count, etc)
+* some minimal set of own metrics (received count, write count, etc.)
 * true multitenancy
 
 The other thing is performance. **Disthene** is being developed with one major requirement in mind - performance. 
@@ -123,7 +123,7 @@ stats:
 Configuration is straight forward as per log4j
 
 ##### Blacklist configuration in blacklist.yaml
-This is a list of regular expressions per tenant. Matching metrics will NOT be store but they still WILL be aggregated (see below)
+This is a list of regular expressions per tenant. Matching metrics will NOT be store, but they still WILL be aggregated (see below)
 
 ##### Whitelist configuration in whitelist.yaml
 This is a list of regular expressions per tenant. Matching metrics will override blacklist rules.
diff --git a/pom.xml b/pom.xml
index 8aedbd0..04900af 100644
--- a/pom.xml
+++ b/pom.xml
@@ -1,10 +1,10 @@
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/maven-v4_0_0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <groupId>net.iponweb.disthene</groupId>
     <artifactId>disthene</artifactId>
     <packaging>jar</packaging>
-    <version>2.0.1</version>
+    <version>2.0.2</version>
     <name>disthene</name>
 
     <properties>
@@ -21,22 +21,22 @@
         <dependency>
             <groupId>org.apache.logging.log4j</groupId>
             <artifactId>log4j-core</artifactId>
-            <version>2.15.0</version>
+            <version>2.17.0</version>
         </dependency>
         <dependency>
             <groupId>org.apache.logging.log4j</groupId>
             <artifactId>log4j-api</artifactId>
-            <version>2.15.0</version>
+            <version>2.17.0</version>
         </dependency>
         <dependency>
             <groupId>org.apache.logging.log4j</groupId>
             <artifactId>log4j-slf4j-impl</artifactId>
-            <version>2.15.0</version>
+            <version>2.17.0</version>
         </dependency>
         <dependency>
             <groupId>io.netty</groupId>
             <artifactId>netty-all</artifactId>
-            <version>4.1.71.Final</version>
+            <version>4.1.72.Final</version>
         </dependency>
         <dependency>
             <groupId>joda-time</groupId>
@@ -71,7 +71,7 @@
         <dependency>
             <groupId>org.lz4</groupId>
             <artifactId>lz4-java</artifactId>
-            <version>1.7.1</version>
+            <version>1.8.0</version>
         </dependency>
         <dependency>
             <groupId>net.engio</groupId>
diff --git a/src/main/java/net/iponweb/disthene/Disthene.java b/src/main/java/net/iponweb/disthene/Disthene.java
index 38f76cc..a1958ac 100644
--- a/src/main/java/net/iponweb/disthene/Disthene.java
+++ b/src/main/java/net/iponweb/disthene/Disthene.java
@@ -105,7 +105,7 @@ private void run() {
             }
 
             BlackListConfiguration blackListConfiguration = new BlackListConfiguration(blacklistRules, whitelistRules);
-            logger.debug("Running with the following blacklist: " + blackListConfiguration.toString());
+            logger.debug("Running with the following blacklist: " + blackListConfiguration);
             blacklistService = new BlacklistService(blackListConfiguration);
 
             logger.info("Creating metric service");
@@ -133,7 +133,7 @@ private void run() {
             in = Files.newInputStream(Paths.get(aggregationConfigLocation));
             AggregationConfiguration aggregationConfiguration = new AggregationConfiguration(yaml.load(in));
             in.close();
-            logger.debug("Running with the following aggregation rule set: " + aggregationConfiguration.toString());
+            logger.debug("Running with the following aggregation rule set: " + aggregationConfiguration);
             logger.info("Creating sum aggregator");
             sumService = new SumService(bus, distheneConfiguration, aggregationConfiguration, blacklistService);
 
@@ -233,7 +233,7 @@ public void handle(Signal signal) {
 
                 blacklistService.setRules(blackListConfiguration);
 
-                logger.debug("Reloaded blacklist: " + blackListConfiguration.toString());
+                logger.debug("Reloaded blacklist: " + blackListConfiguration);
             } catch (Exception e) {
                 logger.error("Reloading blacklists failed");
                 logger.error(e);
@@ -247,7 +247,7 @@ public void handle(Signal signal) {
                 in.close();
 
                 sumService.setAggregationConfiguration(aggregationConfiguration);
-                logger.debug("Reloaded aggregation rules: " + aggregationConfiguration.toString());
+                logger.debug("Reloaded aggregation rules: " + aggregationConfiguration);
             } catch (Exception e) {
                 logger.error("Reloading aggregation rules failed");
                 logger.error(e);
@@ -281,7 +281,7 @@ public void handle(Signal signal) {
             logger.info("Shutting down carbon server");
             carbonServer.shutdown();
 
-            // We will probably loose some last stats here. But leaving it to run will complicate things
+            // We will probably lose some last stats here. But leaving it to run will complicate things
             logger.info("Shutting down stats service");
             statsService.shutdown();
 
diff --git a/src/main/java/net/iponweb/disthene/service/index/IndexService.java b/src/main/java/net/iponweb/disthene/service/index/IndexService.java
index 6d2f0ba..251af9a 100644
--- a/src/main/java/net/iponweb/disthene/service/index/IndexService.java
+++ b/src/main/java/net/iponweb/disthene/service/index/IndexService.java
@@ -84,6 +84,7 @@ public void handle(MetricStoreEvent metricStoreEvent) {
         if (indexConfiguration.isCache()) {
             handleWithCache(metricStoreEvent.getMetric());
         } else {
+            //noinspection ResultOfMethodCallIgnored
             metrics.offer(metricStoreEvent.getMetric());
         }
     }
@@ -93,6 +94,7 @@ private void handleWithCache(Metric metric) {
         Long lastSeen = tenantPaths.put(metric.getPath(), System.currentTimeMillis() / 1000L);
 
         if (lastSeen == null) {
+            //noinspection ResultOfMethodCallIgnored
             metrics.offer(metric);
         }
     }
@@ -126,11 +128,6 @@ public synchronized void invalidateCache() {
     public void shutdown() {
         scheduler.shutdown();
         indexThread.shutdown();
-        logger.info("Sleeping for 10 seconds to allow leftovers to be written");
-        try {
-            Thread.sleep(10000);
-        } catch (InterruptedException ignored) {
-        }
         logger.info("Closing ES client");
 
         try {
diff --git a/src/main/java/net/iponweb/disthene/service/index/IndexThread.java b/src/main/java/net/iponweb/disthene/service/index/IndexThread.java
index 96db340..857c5d6 100644
--- a/src/main/java/net/iponweb/disthene/service/index/IndexThread.java
+++ b/src/main/java/net/iponweb/disthene/service/index/IndexThread.java
@@ -20,6 +20,7 @@
 import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.TimeUnit;
 
 /**
  * @author Andrei Ivanov
@@ -82,16 +83,14 @@ public void run() {
                 Metric metric = metrics.take();
                 addToBatch(metric);
             } catch (Exception e) {
-                logger.warn("Encountered error in busy loop: ", e);
+                if (!shutdown) logger.error("Encountered error in busy loop: ", e);
             }
         }
 
-        if (request.size() > 0) {
-            try {
-                flush();
-            } catch (Exception e) {
-                logger.warn("Encountered error in busy loop: ", e);
-            }
+        try {
+            flush();
+        } catch (Exception e) {
+            logger.error("Encountered error in busy loop: ", e);
         }
     }
 
@@ -104,7 +103,9 @@ private void addToBatch(Metric metric) throws IOException {
         }
     }
 
-    private void flush() throws IOException {
+    private  synchronized void flush() throws IOException {
+        if (request.size() <= 0) return;
+
         MultiGetResponse multiGetResponse = client.mget(request, RequestOptions.DEFAULT);
 
         for (MultiGetItemResponse response : multiGetResponse.getResponses()) {
@@ -123,7 +124,7 @@ private void flush() throws IOException {
                     }
                     sb.append(parts[i]);
                     try {
-                        bulkProcessor.add(new IndexRequest(index).id(metric.getTenant() + "_" + sb.toString()).source(
+                        bulkProcessor.add(new IndexRequest(index).id(metric.getTenant() + "_" + sb).source(
                                 XContentFactory.jsonBuilder().startObject()
                                         .field("tenant", metric.getTenant())
                                         .field("path", sb.toString())
@@ -146,6 +147,21 @@ private void flush() throws IOException {
 
     public void shutdown() {
         shutdown = true;
+
+        logger.info("Flushing leftovers");
+        try {
+            flush();
+            logger.info("Finished flushing leftovers");
+        } catch (IOException e) {
+            logger.error("Flush failed", e);
+        }
+
+        logger.info("Waiting for bulk processor to complete");
+        try {
+            bulkProcessor.awaitClose(1, TimeUnit.MINUTES);
+        } catch (InterruptedException e) {
+            logger.error("AwaitClose interrupted", e);
+        }
         this.interrupt();
     }
 
@@ -154,7 +170,6 @@ private static class MetricMultiGetRequest extends MultiGetRequest {
         private final String index;
         final Map<String, Metric> metrics = new HashMap<>();
 
-
         public MetricMultiGetRequest(String index) {
             this.index = index;
         }
diff --git a/src/main/java/net/iponweb/disthene/service/store/BatchWriterThread.java b/src/main/java/net/iponweb/disthene/service/store/BatchWriterThread.java
index 7485bec..c65faba 100644
--- a/src/main/java/net/iponweb/disthene/service/store/BatchWriterThread.java
+++ b/src/main/java/net/iponweb/disthene/service/store/BatchWriterThread.java
@@ -55,7 +55,7 @@ public void run() {
                 flush();
             }
         } catch (InterruptedException e) {
-            logger.error("Thread interrupted", e);
+            if (!shutdown) logger.error("Thread interrupted", e);
             this.interrupt();
         }
     }
@@ -83,16 +83,18 @@ private void addToBatch(Metric metric) {
         }
     }
 
-    private void flush() {
+    private synchronized void flush() {
         List<List<BatchableStatement<?>>> batches = splitByToken();
 
         for (List<BatchableStatement<?>> batchStatements : batches) {
             BatchStatement batch = BatchStatement.newInstance(BatchType.UNLOGGED, batchStatements);
             final int batchSize = batchStatements.size();
 
+            requestsInFlight.incrementAndGet();
             session
                     .executeAsync(batch)
                     .whenComplete((version, error) -> {
+                        requestsInFlight.decrementAndGet();
                         if (error != null) {
                             bus.post(new StoreErrorEvent(batchSize)).now();
                             logger.error(error);
@@ -117,4 +119,24 @@ private List<List<BatchableStatement<?>>> splitByToken() {
 
         return new ArrayList<>(batches.values());
     }
+
+    @Override
+    public void shutdown() {
+        shutdown = true;
+
+        logger.info("Flushing leftovers");
+        flush();
+
+        while (requestsInFlight.get() > 0) {
+            logger.info("Requests in flight: " + requestsInFlight.get());
+            try {
+                //noinspection BusyWait
+                Thread.sleep(1000);
+            } catch (InterruptedException e) {
+                logger.error("Wait interrupted", e);
+            }
+        }
+
+        this.interrupt();
+    }
 }
diff --git a/src/main/java/net/iponweb/disthene/service/store/CassandraService.java b/src/main/java/net/iponweb/disthene/service/store/CassandraService.java
index 349a06b..fc2167f 100644
--- a/src/main/java/net/iponweb/disthene/service/store/CassandraService.java
+++ b/src/main/java/net/iponweb/disthene/service/store/CassandraService.java
@@ -23,9 +23,7 @@
 import java.time.Duration;
 import java.util.ArrayList;
 import java.util.List;
-import java.util.concurrent.BlockingQueue;
-import java.util.concurrent.Executors;
-import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.*;
 import java.util.stream.Collectors;
 
 /**
@@ -57,6 +55,7 @@ public CassandraService(StoreConfiguration storeConfiguration, MBassador<Disthen
                         .withClass(DefaultDriverOption.REQUEST_THROTTLER_CLASS, ConcurrencyLimitingRequestThrottler.class)
                         .withInt(DefaultDriverOption.REQUEST_THROTTLER_MAX_CONCURRENT_REQUESTS, storeConfiguration.getMaxConcurrentRequests())
                         .withInt(DefaultDriverOption.REQUEST_THROTTLER_MAX_QUEUE_SIZE, storeConfiguration.getMaxQueueSize())
+                        .withClass(DefaultDriverOption.RETRY_POLICY_CLASS, CustomRetryPolicy.class)
                         .build();
 
         CqlSessionBuilder builder = CqlSession.builder()
@@ -115,9 +114,10 @@ private List<String> getContactPoints(StoreConfiguration storeConfiguration) {
         return storeConfiguration.getCluster().stream().map(s -> s + ":" + storeConfiguration.getPort()).collect(Collectors.toList());
     }
 
-    @SuppressWarnings("unused")
+    @SuppressWarnings({"unused"})
     @Handler
     public void handle(MetricStoreEvent metricStoreEvent) {
+        //noinspection ResultOfMethodCallIgnored
         metrics.offer(metricStoreEvent.getMetric());
     }
 
@@ -128,6 +128,7 @@ public void shutdown() {
 
         logger.info("Closing C* session");
         session.close();
+        logger.info("C* session closed");
     }
 }
 
diff --git a/src/main/java/net/iponweb/disthene/service/store/CustomDriverOption.java b/src/main/java/net/iponweb/disthene/service/store/CustomDriverOption.java
new file mode 100644
index 0000000..9be4e2d
--- /dev/null
+++ b/src/main/java/net/iponweb/disthene/service/store/CustomDriverOption.java
@@ -0,0 +1,21 @@
+package net.iponweb.disthene.service.store;
+
+import com.datastax.oss.driver.api.core.config.DriverOption;
+import edu.umd.cs.findbugs.annotations.NonNull;
+
+public enum CustomDriverOption implements DriverOption {
+    CUSTOM_NUMBER_OF_RETRIES("custom.retry-policy.max-retries"),
+    ;
+
+    private final String path;
+
+    CustomDriverOption(String path) {
+        this.path = path;
+    }
+
+    @NonNull
+    @Override
+    public String getPath() {
+        return path;
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/net/iponweb/disthene/service/store/CustomRetryPolicy.java b/src/main/java/net/iponweb/disthene/service/store/CustomRetryPolicy.java
new file mode 100644
index 0000000..9b79870
--- /dev/null
+++ b/src/main/java/net/iponweb/disthene/service/store/CustomRetryPolicy.java
@@ -0,0 +1,43 @@
+package net.iponweb.disthene.service.store;
+
+import com.datastax.oss.driver.api.core.ConsistencyLevel;
+import com.datastax.oss.driver.api.core.context.DriverContext;
+import com.datastax.oss.driver.api.core.retry.RetryDecision;
+import com.datastax.oss.driver.api.core.servererrors.WriteType;
+import com.datastax.oss.driver.api.core.session.Request;
+import com.datastax.oss.driver.internal.core.retry.DefaultRetryPolicy;
+import edu.umd.cs.findbugs.annotations.NonNull;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class CustomRetryPolicy extends DefaultRetryPolicy {
+
+    private static final Logger LOG = LoggerFactory.getLogger(DefaultRetryPolicy.class);
+
+    private final String logPrefix;
+    private final int maxRetries;
+
+    private static final int DEFAULT_MAX_RETRIES = 10;
+
+    public CustomRetryPolicy(DriverContext context, String profileName) {
+        super(context, profileName);
+        this.logPrefix = (context != null ? context.getSessionName() : null) + "|" + profileName;
+
+        maxRetries = context != null ?  context.getConfig().getProfile(profileName).getInt(CustomDriverOption.CUSTOM_NUMBER_OF_RETRIES, DEFAULT_MAX_RETRIES) : DEFAULT_MAX_RETRIES;
+    }
+
+    @SuppressWarnings("deprecation")
+    @Override
+    public RetryDecision onWriteTimeout(@NonNull Request request, @NonNull ConsistencyLevel cl, @NonNull WriteType writeType, int blockFor, int received, int retryCount) {
+        RetryDecision decision =
+                (retryCount <= maxRetries)
+                        ? RetryDecision.RETRY_NEXT
+                        : RetryDecision.RETHROW;
+
+        if (decision == RetryDecision.RETRY_NEXT && LOG.isTraceEnabled()) {
+            LOG.info(
+                    RETRYING_ON_WRITE_TIMEOUT, logPrefix, cl, writeType, blockFor, received, retryCount);
+        }
+        return decision;
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/net/iponweb/disthene/service/store/SingleWriterThread.java b/src/main/java/net/iponweb/disthene/service/store/SingleWriterThread.java
index 37c36f2..d62a221 100644
--- a/src/main/java/net/iponweb/disthene/service/store/SingleWriterThread.java
+++ b/src/main/java/net/iponweb/disthene/service/store/SingleWriterThread.java
@@ -32,7 +32,7 @@ public void run() {
                 store(metric);
             }
         } catch (InterruptedException e) {
-            logger.error("Thread interrupted", e);
+            if (!shutdown) logger.error("Thread interrupted", e);
             this.interrupt();
         }
     }
@@ -44,20 +44,39 @@ private void store(Metric metric) {
             return;
         }
 
-        session.executeAsync(
-                statement.bind(
-                        metric.getRollup() * metric.getPeriod(),
-                        Collections.singletonList(metric.getValue()),
-                        metric.getPath(),
-                        metric.getTimestamp()
-                )).whenComplete((version, error) -> {
-            if (error != null) {
-                bus.post(new StoreErrorEvent(1)).now();
-                logger.error(error);
-            } else {
-                bus.post(new StoreSuccessEvent(1)).now();
-            }
-        });
+        requestsInFlight.incrementAndGet();
+        session
+                .executeAsync(
+                        statement.bind(
+                                metric.getRollup() * metric.getPeriod(),
+                                Collections.singletonList(metric.getValue()),
+                                metric.getPath(),
+                                metric.getTimestamp()
+                        )).whenComplete((version, error) -> {
+                    requestsInFlight.decrementAndGet();
+                    if (error != null) {
+                        bus.post(new StoreErrorEvent(1)).now();
+                        logger.error(error);
+                    } else {
+                        bus.post(new StoreSuccessEvent(1)).now();
+                    }
+                });
     }
 
+    @Override
+    public void shutdown() {
+        shutdown = true;
+
+        while (requestsInFlight.get() > 0) {
+            logger.info("Requests in flight: " + requestsInFlight.get());
+            try {
+                //noinspection BusyWait
+                Thread.sleep(1000);
+            } catch (InterruptedException e) {
+                logger.error("Wait interrupted", e);
+            }
+        }
+
+        this.interrupt();
+    }
 }
diff --git a/src/main/java/net/iponweb/disthene/service/store/WriterThread.java b/src/main/java/net/iponweb/disthene/service/store/WriterThread.java
index 9173b56..ddccaa0 100644
--- a/src/main/java/net/iponweb/disthene/service/store/WriterThread.java
+++ b/src/main/java/net/iponweb/disthene/service/store/WriterThread.java
@@ -7,6 +7,7 @@
 
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.Executor;
+import java.util.concurrent.atomic.AtomicInteger;
 
 /**
  * @author Andrei Ivanov
@@ -24,6 +25,8 @@ public abstract class WriterThread extends Thread {
 
     protected final Executor executor;
 
+    protected final AtomicInteger requestsInFlight = new AtomicInteger(0);
+
     public WriterThread(String name, MBassador<DistheneEvent> bus, CqlSession session, TablesRegistry tablesRegistry, BlockingQueue<Metric> metrics, Executor executor) {
         super(name);
         this.bus = bus;