Partitions should not be removed by custom TTL

@@ -100,7 +100,7 @@ public abstract class AbstractChunkedAggregationTimeseriesDao extends AbstractSq
     }
 
     @Override
-    public ListenableFuture<Integer> savePartition(TenantId tenantId, EntityId entityId, long tsKvEntryTs, String key, long ttl) {
+    public ListenableFuture<Integer> savePartition(TenantId tenantId, EntityId entityId, long tsKvEntryTs, String key) {
         return Futures.immediateFuture(null);
     }
 

@@ -124,7 +124,7 @@ public class TimescaleTimeseriesDao extends AbstractSqlTimeseriesDao implements
     }
 
     @Override
-    public ListenableFuture<Integer> savePartition(TenantId tenantId, EntityId entityId, long tsKvEntryTs, String key, long ttl) {
+    public ListenableFuture<Integer> savePartition(TenantId tenantId, EntityId entityId, long tsKvEntryTs, String key) {
         return Futures.immediateFuture(0);
     }
 

@@ -170,7 +170,7 @@ public class BaseTimeseriesService implements TimeseriesService {
         if (entityId.getEntityType().equals(EntityType.ENTITY_VIEW)) {
             throw new IncorrectParameterException("Telemetry data can't be stored for entity view. Read only");
         }
-        futures.add(timeseriesDao.savePartition(tenantId, entityId, tsKvEntry.getTs(), tsKvEntry.getKey(), ttl));
+        futures.add(timeseriesDao.savePartition(tenantId, entityId, tsKvEntry.getTs(), tsKvEntry.getKey()));
         futures.add(Futures.transform(timeseriesLatestDao.saveLatest(tenantId, entityId, tsKvEntry), v -> 0, MoreExecutors.directExecutor()));
         futures.add(timeseriesDao.save(tenantId, entityId, tsKvEntry, ttl));
     }

@@ -181,11 +181,14 @@ public class CassandraBaseTimeseriesDao extends AbstractCassandraBaseTimeseriesD
     }
 
     @Override
-    public ListenableFuture<Integer> savePartition(TenantId tenantId, EntityId entityId, long tsKvEntryTs, String key, long ttl) {
+    public ListenableFuture<Integer> savePartition(TenantId tenantId, EntityId entityId, long tsKvEntryTs, String key) {
         if (isFixedPartitioning()) {
             return Futures.immediateFuture(null);
         }
-        ttl = computeTtl(ttl);
+        // DO NOT apply custom to partition, otherwise short TTL will remove partition too early
+        // partitions must remain in the DB forever or be removed only by systemTtl
+        // removal of empty partition is too expensive (we need to scan all data keys for this partitions with ALLOW FILTERING)
+        long ttl = computeTtl(0);
         long partition = toPartitionTs(tsKvEntryTs);
         if (cassandraTsPartitionsCache == null) {
             return doSavePartition(tenantId, entityId, key, ttl, partition);

@@ -33,7 +33,7 @@ public interface TimeseriesDao {
 
     ListenableFuture<Integer> save(TenantId tenantId, EntityId entityId, TsKvEntry tsKvEntry, long ttl);
 
-    ListenableFuture<Integer> savePartition(TenantId tenantId, EntityId entityId, long tsKvEntryTs, String key, long ttl);
+    ListenableFuture<Integer> savePartition(TenantId tenantId, EntityId entityId, long tsKvEntryTs, String key);
 
     ListenableFuture<Void> remove(TenantId tenantId, EntityId entityId, DeleteTsKvQuery query);
 

@@ -100,10 +100,10 @@ public class CassandraPartitionsCacheTest {
         long tsKvEntryTs = System.currentTimeMillis();
 
         for (int i = 0; i < 50000; i++) {
-            cassandraBaseTimeseriesDao.savePartition(tenantId, tenantId, tsKvEntryTs, "test" + i, 0);
+            cassandraBaseTimeseriesDao.savePartition(tenantId, tenantId, tsKvEntryTs, "test" + i);
         }
         for (int i = 0; i < 60000; i++) {
-            cassandraBaseTimeseriesDao.savePartition(tenantId, tenantId, tsKvEntryTs, "test" + i, 0);
+            cassandraBaseTimeseriesDao.savePartition(tenantId, tenantId, tsKvEntryTs, "test" + i);
         }
         verify(cassandraBaseTimeseriesDao, times(60000)).executeAsyncWrite(any(TenantId.class), any(Statement.class));
     }