With subsequent executions, LINQPad uses the same process and so anything that's cached in memory by your script will benefit in performance. This hasn't changed in any recent LINQPad update.

A simple script in LINQPad takes maybe tens of milliseconds to compile, so that shouldn't be the issue. And NuGet references are not normally copied anywhere - LINQPad loads them directly from the machine cache.

Have you tried the same thing on another machine?

Something else to keep in mind is that the operating system also caches recently accessed data on the hard drive, so that will affect performance, too.

I am trying to connect to local postgresql db and unable to connect, keep getting the error in attached png. Any suggestion?
Thanks,
Salil

It sounds like a reference assembly is somehow ending up in your project's output folder. Can you verify that System.IO.Compression.* is not present in your output folder?

Replace the call to Thread.Sleep with:

await Task.Delay(1000);

Another option, if you need just a simple button and not a WPF button, is to use LINQPad's HTML controls, i.e., LINQPad.Controls.Button:

var button = new LINQPad.Controls.Button ("test") { IsMultithreaded = true };
button.Click += (sender, args) => button.Text = "I've just been clicked!";
button.Dump();
Thread.Sleep(1000);

No need to add the dll, just reference it, eg System.Web.HttpUtility.HtmlEncode("1&2").Dump();

There's no longer an option to add Framework assembly references. In keeping with Visual Studio, all .NET Core Framework assemblies are referenced automatically.

From the Things that behave differently in LINQPad 6 section of https://www.linqpad.net/LINQPad6.asp

Also note that when you create the connection in LINQPad 6, you have the option of choosing EF Core instead of LINQ-to-SQL. If you choose EF Core, you'll be able to call this.Database.ExecuteSqlInterpolated.

Use the built in ExecuteQuery<T> or ExecuteQueryDynamic function

Or use int ExecuteCommand(string command, params object[] parameters) if your statement does not return data.

Hope this is not out of place. But I just wanted to post a huge

THANK YOU!!!

I've been using LINQPad for years in much the same way as OP to prototype ideas and sometimes they get fairly complex and lengthy. And this has been a very significant pain point for me, that the editing gets incredibly slow after awhile. I am so happy that the root cause of this has been uncovered. Please accept my sincerest gratitude!

Best Regards,
~ mellamokb

Any chance we can choose a remapping for escape from insert mode? I am grateful for the "kj" mapping, but I've been a "jk" user for a long time and it's hard to transition.

Also, is there a way to turn off LINQPad's ctrl-[ mapping (surround with brackets)? This is an alias for ESC in vim (and unix tty in general).

Love vi in LINQPad. Thanks for all your hard work!

You could use the following script to compile the dll and get a reference to the most recent generated file in the temporary folder within the same application lifetime.

Util.Compile(@"C:\Drive\Projects\LINQPad\Queries\Sample.linq");

var path = Path.Combine(Path.GetTempPath(), "LINQPad5", $"_{AppDomain.CurrentDomain.GetData("LINQPad.InstanceID")}");

var file =
  new DirectoryInfo(path)
    .EnumerateFiles("*.dll") // Or query_*.dll
    .OrderBy(x => x.LastWriteTime)
    .Last();

file.FullName.Dump();