Tag Info

New answers tagged

4

By system clock I mean the clock that tells the time down right of the panel "System clock" generally refers to the clock maintained by the kernel; applications such as date and GUI clocks such as the one you refer to make calls to it like this. Why, out of all the processes that the system runs, does the clock need a shared memory segment? ...


0

Check your .config for CONFIG_RTC_DRV_CMOS=y, CONFIG_RTC_INTF_DEV=y (create the /dev/rtcN device) and CONFIG_RTC_CLASS=y (which the other two depend on). In menuconfig, these are under Device Drivers -> Real Time Clock. I do not a discrepancy in the default x86* configs, both of which set CONFIG_RTC_CLASS. When making a defconfig on x86_64 with v3.12 ...


0

The Hardware Clock is a clock that runs independently of any control program running in the CPU and even when the machine is powered off. The System Time is the time kept by a clock inside the Linux kernel. Some programs and fringe parts of the Linux kernel such as filesystems use the kernel timezone value. An example is the vfat filesystem. If the kernel ...


2

Well, first of all, the kernel chooses the best one automatically, it is usually TSC if it's available, because it's kept by the cpu and it's very fast (RDTSC and reading EDX:EAX). But that wasn't always the case, in the early days when the SMP systems were mostly built with several discrete cpus it was very important that the cpus where as "equal" as it ...



Top 50 recent answers are included