Reading from a non-existent database causes memory usage to grow #1089

import com.google.cloud.spanner.DatabaseId;
import com.google.cloud.spanner.InstanceConfigId;
import com.google.cloud.spanner.InstanceId;
import com.google.cloud.spanner.InstanceInfo;
import com.google.cloud.spanner.Key;
import com.google.cloud.spanner.Spanner;
import com.google.cloud.spanner.SpannerOptions;
import java.util.Arrays;
import org.junit.Test;

public class FailedRequestMemoryUsageTest {

  @Test
  public void testFailedRequestMemoryUsage() throws Exception {
    Spanner spanner = SpannerOptions.getDefaultInstance().getService();
    String projectId = spanner.getOptions().getProjectId();
    InstanceId instanceId = InstanceId.of(projectId, "my-instance");
    InstanceConfigId instanceConfigId = InstanceConfigId.of(projectId, "regional-us-central1");
    spanner
        .getInstanceAdminClient()
        .createInstance(
            InstanceInfo.newBuilder(instanceId)
                .setInstanceConfigId(instanceConfigId)
                .setDisplayName("my-instance")
                .setNodeCount(1)
                .build())
        .get();
    DatabaseId databaseId = DatabaseId.of(instanceId, "my-database");

    for (int i = 0; i <= 10000; i++) {
      if (i % 500 == 0) {
        Runtime.getRuntime().gc();
        System.out.println(
            i + "\t" + (Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()));
      }
      try {
        spanner
            .getDatabaseClient(databaseId)
            .singleUse()
            .readRow("MyTable", Key.of(0), Arrays.asList("MyColumn"));
      } catch (Exception e) {
        // Ignore NOT_FOUND error
      }
    }
  }
}