"Generally, a large number of context switches is bad for performance when KAISER is applied," referring to KAISER, a kernel isolation technique, which Gruss wrote a paper about last year.
"For instance doing a lot of accesses to small files, you might have slow downs of 50 percent or more," he confirmed.
The researchers said it wasn't known if either bug had been exploited by attackers to date.
The UK's National Cyber Security Center also said it too has seen "no evidence" of any malicious exploitation.
"Intel believes these exploits do not have the potential to corrupt, modify or delete data." Incoming patches are expected to prevent attackers from exploiting the chips' design flaw, but have prompted concern that chip performance will be degraded as a result.
Meltdown lets an attacker access whatever is in the affected device's memory, including sensitive files and data, by melting down the security boundaries typically held together by the hardware.
Microsoft released patches for Windows, outside its usual Patch Tuesday update schedule -- Windows Insiders on the fast-ring already received the patches in November.
Apple reportedly patched the flaw in mac OS 10.13.2.
A spokesperson did not respond to a request for comment. Many cloud services running Intel-powered servers are also affected, prompting Amazon, Microsoft, and Google to patch their cloud services and schedule downtime to prevent would-be attackers from reading other processes on the same shared cloud server.
Microsoft and Amazon have announced scheduled downtime of their cloud services in the coming days.