Best way to avoid parallel execution

question
1

I’m trying to find a way to avoid parallel method execution with multiple workers.

I have A, B and C methods to enqueue into hangfire server. And these method will be enqueued many times.
For example, when queue is like this [A1, A2, B1, B2, C1, B3, C2] and worker count is 3.
I want to avoid the situation that two method A work at the same time since A method requires huge memory.

   [worker1: A1, worker2: A2, worker3: B1] <- avoid the situation...

But B and C need to work in parallel.

   [worker1: A1, worker2: B1, worker3: B2]
   [worker1: C1, worker2: A2, worker3: B3]

Any idea?
Thanks!

2

Run two servers, one with a single worker that executes just A jobs; and another with as many workers as you need for B and C jobs.

3

Thank you for your idea!
I tried to implement your suggestion on an ASP.NET app like the following and it worked!

  • Startup.cs
public class Startup
{
    public void Configuration(IAppBuilder app)
    {
        GlobalConfiguration.Configuration.UseSqlServerStorage(
             "Server=localhost;Database=Hangfire;");
        app.UseHangfireDashboard();
        app.UseHangfireServer(new BackgroundJobServerOptions { ServerName = "server1", WorkerCount = 1 });
        app.UseHangfireServer(new BackgroundJobServerOptions { ServerName = "server2", WorkerCount = 5 });
    }
}
  • HomeController.cs
public class HomeController : Controller
{
    public ActionResult Index(int job)
    {
        using (var server = new BackgroundJobServer(
                 new BackgroundJobServerOptions { ServerName = "server1" }))
        {
            BackgroundJob.Enqueue(() => DoHeavyJob());
        }

        using (var server = new BackgroundJobServer(
                     new BackgroundJobServerOptions { ServerName = "server2" }))
            {
                 BackgroundJob.Enqueue(() => DoLightJob);
            }
            ...
        }
}