#362: Cache index table metadata in tserver when updating an index

Summary: Cache index table metadata in tserver when updating an index for performance. The cache is invalidated when the indexed table is altered. Test Plan: ``` java -jar ~/code/yugabyte/java/yb-loadtester/target/yb-sample-apps.jar -workload CassandraSecondaryIndex -num_threads_read 0 -num_threads_write 4 -nodes 127.0.0.1:9042 ``` Without cache: ``` 2018-07-05 17:07:41,973 [INFO|com.yugabyte.sample.common.metrics.MetricsTracker|MetricsTracker] Read: 0.00 ops/sec (0.00 ms/op), 0 total ops | Write: 215.81 ops/sec (18.53 ms/op), 3517 total ops | Uptime: 25015 ms | maxWrittenKey: 3514 | maxGeneratedKey: 3520 | 2018-07-05 17:07:46,976 [INFO|com.yugabyte.sample.common.metrics.MetricsTracker|MetricsTracker] Read: 0.00 ops/sec (0.00 ms/op), 0 total ops | Write: 217.65 ops/sec (18.37 ms/op), 4606 total ops | Uptime: 30018 ms | maxWrittenKey: 4605 | maxGeneratedKey: 4609 | 2018-07-05 17:07:51,979 [INFO|com.yugabyte.sample.common.metrics.MetricsTracker|MetricsTracker] Read: 0.00 ops/sec (0.00 ms/op), 0 total ops | Write: 212.29 ops/sec (18.82 ms/op), 5668 total ops | Uptime: 35021 ms | maxWrittenKey: 5665 | maxGeneratedKey: 5671 | ``` With cache: ``` 2018-07-05 17:12:24,773 [INFO|com.yugabyte.sample.common.metrics.MetricsTracker|MetricsTracker] Read: 0.00 ops/sec (0.00 ms/op), 0 total ops | Write: 229.69 ops/sec (17.42 ms/op), 2892 total ops | Uptime: 20015 ms | maxWrittenKey: 2891 | maxGeneratedKey: 2895 | 2018-07-05 17:12:29,776 [INFO|com.yugabyte.sample.common.metrics.MetricsTracker|MetricsTracker] Read: 0.00 ops/sec (0.00 ms/op), 0 total ops | Write: 231.24 ops/sec (17.31 ms/op), 4049 total ops | Uptime: 25018 ms | maxWrittenKey: 4048 | maxGeneratedKey: 4052 | 2018-07-05 17:12:34,781 [INFO|com.yugabyte.sample.common.metrics.MetricsTracker|MetricsTracker] Read: 0.00 ops/sec (0.00 ms/op), 0 total ops | Write: 235.37 ops/sec (16.97 ms/op), 5227 total ops | Uptime: 30023 ms | maxWrittenKey: 5225 | maxGeneratedKey: 5230 | ``` Also verify that no further RPC is executed at the master leader when the workload is run. Reviewers: pritam.damania, amitanand, mihnea Reviewed By: mihnea Subscribers: ybase, yql Differential Revision: https://phabricator.dev.yugabyte.com/D5112
yugabyte · Jul 6, 2018 · 2ebadb8 · 2ebadb8
1 parent 4dd62b7
commit 2ebadb8
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Showing 2 changed files with 28 additions and 12 deletions.
diff --git a/src/yb/tablet/tablet.cc b/src/yb/tablet/tablet.cc
@@ -364,6 +364,11 @@ Tablet::Tablet(
     }
   }
 
+  // Create index table metadata cache for secondary index update.
+  if (!metadata_->index_map().empty()) {
+    metadata_cache_.emplace(client_future_.get());
+  }
+
   // TODO(dtxn) Create coordinator only for status tablets
   if (transaction_coordinator_context) {
     transaction_coordinator_ = std::make_unique<TransactionCoordinator>(
@@ -901,7 +906,12 @@ Status Tablet::UpdateQLIndexes(docdb::DocOperations* doc_ops) {
     vector<std::pair<const IndexInfo*, shared_ptr<client::YBqlWriteOp>>> index_ops;
     for (auto& pair : *write_op->index_requests()) {
       client::YBTablePtr index_table;
-      RETURN_NOT_OK(client->OpenTable(pair.first->table_id(), &index_table));
+      bool cache_used_ignored = false;
+      if (!metadata_cache_) {
+        return STATUS(Corruption, "Table metadata cache is not present for index update");
+      }
+      RETURN_NOT_OK(metadata_cache_->GetTable(pair.first->table_id(), &index_table,
+                                              &cache_used_ignored));
       shared_ptr<client::YBqlWriteOp> index_op(index_table->NewQLWrite());
       index_op->mutable_request()->Swap(&pair.second);
       index_op->mutable_request()->MergeFrom(pair.second);
@@ -1215,18 +1225,22 @@ Status Tablet::AlterSchema(AlterSchemaOperationState *operation_state) {
       }
     }
 
+    // Clear old index table metadata cache.
+    metadata_cache_ = boost::none;
+
     // Update the index info.
     metadata_->SetIndexMap(std::move(operation_state->index_map()));
 
-    // Create transaction manager for secondary index update.
-    if (!metadata_->index_map().empty() &&
-        metadata_->schema().table_properties().is_transactional() &&
-        !transaction_manager_) {
-      const auto transaction_participant_context =
-          DCHECK_NOTNULL(transaction_participant_.get())->context();
-      transaction_manager_.emplace(client_future_.get(),
-                                   transaction_participant_context->clock_ptr(),
-                                   local_tablet_filter_);
+    // Create transaction manager and index table metadata cache for secondary index update.
+    if (!metadata_->index_map().empty()) {
+      if (metadata_->schema().table_properties().is_transactional() && !transaction_manager_) {
+        const auto transaction_participant_context =
+            DCHECK_NOTNULL(transaction_participant_.get())->context();
+        transaction_manager_.emplace(client_future_.get(),
+                                     transaction_participant_context->clock_ptr(),
+                                     local_tablet_filter_);
+      }
+      metadata_cache_.emplace(client_future_.get());
     }
 
     // If the current schema and the new one are equal, there is nothing to do.

diff --git a/src/yb/tablet/tablet.h b/src/yb/tablet/tablet.h
@@ -46,7 +46,7 @@
 
 #include "yb/tserver/tserver.pb.h"
 
-#include "yb/client/client_fwd.h"
+#include "yb/client/client.h"
 #include "yb/client/transaction_manager.h"
 
 #include "yb/common/schema.h"
@@ -638,9 +638,11 @@ class Tablet : public AbstractTablet, public TransactionIntentApplier {
 
   std::unique_ptr<TransactionParticipant> transaction_participant_;
 
-  // Created only when secondary indexes are present.
   std::shared_future<client::YBClientPtr> client_future_;
+
+  // Created only when secondary indexes are present.
   boost::optional<client::TransactionManager> transaction_manager_;
+  boost::optional<client::YBMetaDataCache> metadata_cache_;
 
   std::atomic<int64_t> last_committed_write_index_{0};