Question: i have a caliper benchmark (1.0-beta-2):

```
import com.google.caliper.Benchmark;
import com.google.caliper.runner.CaliperMain;

public class MyBenchmark {

    @Benchmark public int a(int rep) {
        return 0;
    }

    public static void main(String[] args) {
        CaliperMain.main(MyBenchmark.class, args);
    }   
}

```

i run it from eclipse or from command line with:

```
mvn exec:java -Dexec.mainClass="com.google.caliper.runner.CaliperMain" -Dexec.args="MyBenchmark" 

```

in both cases i got an error:

```
ERROR: Trial failed to complete (its results will not be included in the run):
  The worker exited without producing data. It has likely crashed. Inspect /tmp/1427055470061-0/trial-1.log to see any worker output.

```

in this file i see:

```
Trial Number: 1
Trial Id: d663a0b5-55b4-43c3-97d8-93f14f436342
Experiment: {instrument=allocation, benchmarkMethod=a, vm=default, parameters={}}

[stderr] CICompilerCount of 1 is invalid; must be at least 2
[stderr] Error: Could not create the Java Virtual Machine.
[stderr] Error: A fatal exception has occurred. Program will exit.

```

ubuntu 14.04, java:

```
java version "1.8.0_40"
Java(TM) SE Runtime Environment (build 1.8.0_40-b25)
Java HotSpot(TM) 64-Bit Server VM (build 25.40-b25, mixed mode)

```

any ideas how to fix it?

Answer: 
i found a solution. flag `-XX:-TieredCompilation` helps. it can be used directly in microbenchmark java class as:

```
import com.google.caliper.api.VmOptions;

@VmOptions("-XX:-TieredCompilation")
public class MyMicrobenchmark {
...

```
It's a bug in Caliper. It uses `-XX:CICompilerCount=1` as a default JVM argument. However, when Tiered compilation is on, there must be at least 2 compiler threads (one for C1 and one for C2).

Try overriding `-XX:CICompilerCount` manually with a larger value.