Xcode 11 debugger is extremely slow - A known problem?

Question

Since I updated to the latest Xcode version 11.0 (11A420a) the debugging is extremely slow and cumbersome.

EDIT: After updating to 11.1 GM (11A1027

Answer 1

I've seen some performance improvements when using the Whole versus Incremental Compilation behavior. Additionally running on Mojave and Catalina should both be showing performance issues. Specifically since the Canvas preview and other new features require more CPU intensity than the last version of Xcode, I would expect Mojave performance to be lower when using Xcode 11 (as it's not optimized for this version of the OS). With Catalina being in Beta, I'd expect to see additional issues as well. I haven't taken specific measures other than the eye-test. The initial run on Whole Compilation is slow but seems to get better thereafter.

Quick help states:

Summary

This setting controls the way the Swift files in a module are rebuilt. * Incremental: Only rebuild the Swift source files in the module that are out of date, running multiple compiler processes as needed. * Whole Module: Always rebuild all Swift source files in the module, in a single compiler process. Declaration

SWIFT_COMPILATION_MODE Value Type

Enumeration (String)