Print before AddErrors in stress tests (#6256)

Summary:
Stress tests count number of errors and report them at the end. Not all the cases are accompanied with a log line which makes debugging difficult. The patch adds a log line to the remaining cases.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6256

Differential Revision: D19268785

Pulled By: maysamyabandeh

fbshipit-source-id: bdabcaa5c5c7edcb4ce4f25e38fd8a3fd9c7700b

db_stress_tool/batched_ops_stress.cc

@@ -325,6 +325,7 @@ class BatchedOpsStressTest : public StressTest {
     if (s.ok()) {
       thread->stats.AddPrefixes(1, count);
     } else {
+      fprintf(stderr, "TestPrefixScan error: %s\n", s.ToString().c_str());
       thread->stats.AddErrors(1);
     }
 

db_stress_tool/cf_consistency_stress.cc

@@ -184,6 +184,7 @@ class CfConsistencyStressTest : public StressTest {
       db_->ReleaseSnapshot(snapshot);
     }
     if (!is_consistent) {
+      fprintf(stderr, "TestGet error: is_consistent is false\n");
       thread->stats.AddErrors(1);
       // Fail fast to preserve the DB state.
       thread->shared->SetVerificationFailure();
@@ -192,6 +193,7 @@ class CfConsistencyStressTest : public StressTest {
     } else if (s.IsNotFound()) {
       thread->stats.AddGets(1, 0);
     } else {
+      fprintf(stderr, "TestGet error: %s\n", s.ToString().c_str());
       thread->stats.AddErrors(1);
     }
     return s;
@@ -225,6 +227,7 @@ class CfConsistencyStressTest : public StressTest {
         thread->stats.AddGets(1, 0);
       } else {
         // errors case
+        fprintf(stderr, "MultiGet error: %s\n", s.ToString().c_str());
         thread->stats.AddErrors(1);
       }
     }
@@ -263,6 +266,7 @@ class CfConsistencyStressTest : public StressTest {
     if (s.ok()) {
       thread->stats.AddPrefixes(1, count);
     } else {
+      fprintf(stderr, "TestPrefixScan error: %s\n", s.ToString().c_str());
       thread->stats.AddErrors(1);
     }
     delete iter;

db_stress_tool/db_stress_test_base.cc

@@ -955,6 +955,7 @@ Status StressTest::TestIterate(ThreadState* thread,
     if (s.ok()) {
       thread->stats.AddIterations(1);
     } else {
+      fprintf(stderr, "TestIterate error: %s\n", s.ToString().c_str());
       thread->stats.AddErrors(1);
       break;
     }

db_stress_tool/no_batched_ops_stress.cc

@@ -147,6 +147,7 @@ class NonBatchedOpsStressTest : public StressTest {
       thread->stats.AddGets(1, 0);
     } else {
       // errors case
+      fprintf(stderr, "TestGet error: %s\n", s.ToString().c_str());
       thread->stats.AddErrors(1);
     }
     return s;
@@ -243,6 +244,7 @@ class NonBatchedOpsStressTest : public StressTest {
         thread->stats.AddGets(1, 0);
       } else {
         // errors case
+        fprintf(stderr, "MultiGet error: %s\n", s.ToString().c_str());
         thread->stats.AddErrors(1);
       }
     }
@@ -277,6 +279,7 @@ class NonBatchedOpsStressTest : public StressTest {
     if (iter->status().ok()) {
       thread->stats.AddPrefixes(1, count);
     } else {
+      fprintf(stderr, "TestPrefixScan error: %s\n", s.ToString().c_str());
       thread->stats.AddErrors(1);
     }
     delete iter;