You have heard about the CPU architecture problems in the media.
A few days ago I made a performance snapshot of an Intel Pentium N4200 notebook:
Pianoteq on a low performance mini pc
Today the first patches to work-around the "Meltdown" part appeared on my platform.
I repeated the test with the new patched kernel and fortunately Pianoteq's Performance index is the same as before.
Cheers
That doesn't surprise, Pianoteq is a number-crunching application, it doesn't make nearly as many context switches from user mode to kernel mode for the impact of the Meltdown fix to be of any significance.
Reports are that while some headline figures for slowdown are quoting between 20% and 30%, these are for high workload systems making lots of I/O subsystem calls and switching between different processes and threads - typically servers under load.
In practice desktop system running e.g. pianoteq, browsers and even games make relatively few of the relevant context shifts and initial reports are that these are only minimally affected - perhaps a few percent at most. It's early days.
In any case Pianoteq itself seems to require very little power in absolute terms, so I'd expect minimal impact on Pianoteq itself. Things may get more involved in scenarios where people are running pianoteq as a VST instrument using a lot more MIDI work and a lot more audio tracks. Sampled instruments may be more affected - in theory they use more system I/O than a modeled instrument like Pianoteq's. It's rather early days to see how this works and I'd also expect OS makers to try and improve the performance of patches if possible.
The main issue with the need to patch systems is purely for security reasons as it is thought that at least one of these vulnerabilities could, in principle, be exploited by hostile code. However AFAIK no actual exploits have been seen in the wild, just lab demos within the security community.