The Meltdown/Spectre saga: The impact across millions of cores

On January 3rd, an unexpected spike in CPU usage was observed across large Redis instances due to the disclosure of Meltdown and Spectre vulnerabilities and subsequent patches. The average impact on system.cpu.system was less than 1%, but the widespread issue affected millions of cores running varying workloads. Hosts with more system CPU usage experienced a higher-magnitude impact, while compute-optimized and general-purpose virtual machines were most affected. This large-scale analysis confirms the significant performance impact of these security patches and highlights the potential for future vulnerabilities in this class.