TestSystem7.cs

using UnityEngine;
using Unity.Entities;
using Unity.Jobs;
using Unity.Collections;

public class TestSystem7 : JobComponentSystem
{
    protected override JobHandle OnUpdate(JobHandle inputDeps)
    {
        var handle1 = new Process1().ScheduleSingle(this, inputDeps);
        var handle2 = new Process2().ScheduleSingle(this, inputDeps);

        return JobHandle.CombineDependencies(handle1, handle2);
    }

    struct Process1 : IJobProcessComponentData<SampleData1>
    {
        public void Execute([ReadOnly]ref SampleData1 data)
        {
            Debug.Log("sample7 p1");
        }
    }
    struct Process2 : IJobProcessComponentData<SampleData2>
    {
        public void Execute(ref SampleData2 data)
        {
            Debug.Log("sample7 p2");
        }
    }
}

TestSystem8.cs

using UnityEngine;
using Unity.Entities;
using Unity.Jobs;
using Unity.Collections;

public class TestSystem8 : JobComponentSystem
{
    protected override JobHandle OnUpdate(JobHandle inputDeps)
    {
        var handle1 = new Process1().ScheduleSingle(this, inputDeps);
        var handle2 = new Process2().ScheduleSingle(this, inputDeps);

        return JobHandle.CombineDependencies(handle1, handle2);
    }

    struct Process1 : IJobProcessComponentData<SampleData1>
    {
        public void Execute([ReadOnly] ref SampleData1 data)
        {
            Debug.Log("sample8 p1");
        }
    }
    struct Process2 : IJobProcessComponentData<SampleData2>
    {
        public void Execute([ReadOnly]ref SampleData2 data)
        {
            Debug.Log("sample8 p2");
        }
    }
}