According to the report, “Crucially, these updates to both Linux and Windows will incur a performance hit on Intel products. The effects are still being benchmarked, however we’re looking at a ballpark figure of five to 30 per cent slow down, depending on the task and the processor model. More recent Intel chips have features – such as PCID – to reduce the performance hit.”
This is also expected to affect Apple’s macOS operating system, where a microcode update can’t address the issue and that a fix needs to be made at the OS level. Alternatively The Register claims that you could buy a new processor that comes without the flaw. Unfortunately details about the flaw are relatively scarce at this point in time, with the information reportedly under embargo, presumably to keep it under wraps until fixes can be issued to prevent hackers from exploiting it.
No word on when the fixes are being issued, but Microsoft and Linux developers are already working on it, so hopefully it will be sooner rather than later.