以Linux为例,查看操作系统的clocksource: 在/sys/devices/system/clocksource/clocksource0目录下; available_clocksource是当前所有可用的clocksource; current_clocksource是当前正在使用的clocksource。 所以,先不管这些名词是什么东西,怎么实现的,起码kvm-clock、tsc、hpet、acpi_pm是同一类的东西;并且,在Linux上,统一管理...
TSC PIT,HPET,ACPI_PM,这些硬件以一定的频率产生时钟中断,来帮助我们计时。Linux为了管理这些硬件,抽象出来clocksource。 前面提到了Linux下的时间相关的硬件。TSC PIT,HPET,ACPI_PM,这些硬件以一定的频率产生时钟中断,来帮助我们计时。Linux为了管理这些硬件,抽象出来clocksource。 复制 struct clocksource {/** Hotpath...
clocksource: Switched to clocksource hpet The above warning message is generated when the skew between the periods measured by HPET and TSC exceeds 0.0625 seconds. The counter values for HPET show that HPET overflowed and the period elapsed since the last check was 131.020 seconds: 0xffffffff + ...
例如,输出可能是tsc、hpet、acpi_pm等,这些都是Linux内核支持的不同的时钟源。 通过上述步骤,你可以轻松地查看Linux系统的clocksource配置。如果你对某个特定的clocksource有进一步的疑问或需要更改配置,你可能需要查阅更多的Linux内核文档或咨询更专业的技术支持。
Slow system clocksource detected. This can result in degraded performance. Consider changing the system's clocksource. Current clocksource: xen. Available clocksources: xen tsc hpet acpi_pm. For example: run the command 'echotsc > /sys/devices/system/clocksource/clocksource0/current_clocksource' as...
[ 821.067990] clocksource: Switched to clocksource hpet This can be reproduced by running memory intensive 'stream' tests, or some of the stress-ng subcases such as 'ioport'. The reason for these issues is the when system is under heavy load, the read latency of the clocksources can be ...
但是,TSC不同与HPET等时钟,它的频率不是预知的。因此,内核必须在初始化过程中,利用HPET,PIT等始终来校准TSC的频率。如果两次校准结果偏差较大,则认为TSC是不稳定的,则使用其它时钟源。并打印内核日志:Clocksource tsc unstable. 正常来说,TSC的频率很稳定且不受CPU调频的影响(如果CPU支持constant-tsc)。内核不应该...
tsc hpet acpi_pm TSC:The timestamp counteris a clock implemented within the processor on x86 architectures. As such it is very fast and has a high granularity (Ghz). It also has a good capacity. Due to its nature, it is a per-CPU clock with a reliability/stability that may vary acro...
Linux 4.5.0 on x86_64 with /sys/devices/system/clocksource/clocksource0/current_clocksource set to hpet: $ ./clockperf clockperf v1.0.0 Invariant TSC: Yes tsc resolution = 2402MHz realtime resolution = 1000MHz realtime_crs resolution = 100Hz monotonic resolution = 1000MHz monotonic_crs resol...
解决 将时钟源更改为系统上另一个可用的时钟 首先,找到可用的系统时钟源: $ cat/sys/devices/system/clocksource/clocksource0/available_clocksource 结果示例如下: $ cat/sys/devices/system/clocksource/clocksource0/available_clocksource tsc hpet acpi_pm ...