TestSystem1.cs

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

public class TestSystem1 : JobComponentSystem
{
    protected override JobHandle OnUpdate(JobHandle inputDeps)
    {
        return new Process().ScheduleSingle(this, inputDeps);
    }

    struct Process : IJobProcessComponentData<SampleData1>
    {
        public void Execute(ref SampleData1 data)
        {
            Debug.Log("sample1");
        }
    }
}

TestSystem2.cs

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

public class TestSystem2 : JobComponentSystem
{
    protected override JobHandle OnUpdate(JobHandle inputDeps)
    {
        return new Process().ScheduleSingle(this, inputDeps);
    }

    struct Process : IJobProcessComponentData<SampleData2>
    {
        public void Execute(ref SampleData2 data)
        {
            Debug.Log("sample2");
        }
    }
}