红帽全球峰会17.5. 在 Opteron CPU 上同步 TSC 计时器
当前的 AMD64 Opteron 处理器对于一个大型 gettimeofday skew 可能很易受。当 cpufreq 和 时间戳计数器 (TSC)都被使用时，会出现这个偏移。RHEL for Real Time 提供了通过强制所有处理器同时更改为相同频率来防止这种偏移的方法。因此，单个处理器上的 TSC 不会以不同于其他处理器上的 TSC 的速度增加。
先决条件
- 您在系统上具有 root 权限。
流程
启用
clocksource=tsc和powernow-k8.tscsync=1内核选项：grubby --update-kernel=ALL --args="clocksource=tsc powernow-k8.tscsync=1"
# grubby --update-kernel=ALL --args="clocksource=tsc powernow-k8.tscsync=1"Copy to Clipboard Copied! Toggle word wrap Toggle overflow 这会强制使用 TSC，并启用同时核心处理器频率转换。
- 重启机器。
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