McAfee FileCore kernel extension slows down file copying
I write backup software (Carbon Copy Cloner, https://bombich.com), and one of my users reported that his backup task was running excruciatingly slow, especially as it copied individual email documents (i.e. .emlx documets in ~/Library/Mail/V5/...). The user noted that this same performance degradation occurred when he tried to copy the same items via the Finder.
I asked the user to collect a spindump when the performance issue was occurring, and the stack trace of my file copier shows severe performance degradation caused by the McAfee "FileCore.kext" kernel extension:
This is not the first incident of FileCore interference that has been reported to me, so I would like someone on the FMP engineering team to investigate and resolve the performance problem in this "handleFileIOEvent" method.