Some Users Experiencing System Crashes on macOS 10.15.4, Especially During Large File Transfers

A sizeable number of Mac users are experiencing occasional system crashes after updating to macOS Catalina version 10.15.4, released a few weeks ago. From a report: The crashing issue appears to be most prominent when users attempt to make large file transfers. In a forum post, SoftRAID described the issue as a bug and said that it is working with Apple engineers on a fix for macOS 10.15.5, or a workaround. “SoftRAID said the issue extends to Apple-formatted disks: There is a serious issue with 10.15.4. It shows up in different scenarios, even on Apple disks but is more likely when there are lots of IO threads. We think it is a threading issue. So while SoftRAID volumes are hit the hardest (it’s now hard to copy more than 30GB of data at a time), all systems are impacted by this. In our bug report to Apple, we used a method to reproduce the problem with ONLY Apple formatted disks. Takes longer to reproduce, but that is more likely to get a faster fix to the user base.”