# Set jiffies to 1000HZ = slow system time clock

## saiyan

My system: AMD 2100+ running on ASUS A7N266-C motherboard.

Kernel: gentoo-sources-2.4.19-r7

Observation: System clock loses about 1 second every 2 minutes when CPU is nearly idle.  It loses 3+ seconds per minute when CPU is busy (ie when compiling programs).

Someone suggested changing the setting for jiffies to 100HZ may help.  So I made the change and after a kernel re-compilation, the problem disappeared.  So far the system clock has been consistently about 2 seconds slower than the hardware clock after 7 hours of uptime and numerous emerges.

root # hwclock --show ; date

Sun Jul 14 12:36:00 2002  -0.296559 seconds

Sun Jul 14 12:35:58 PDT 2002

root # hwclock --show ; date

Sun Jul 14 19:33:26 2002  -0.165589 seconds

Sun Jul 14 19:33:24 PDT 2002

Someone in this forum has pointed out the default jiffies in the vanilla kernel source is 100HZ. I wonder if the system clock algorithm in the kernel was designed to work with 100HZ jiffies.

If future release of kernels are going to use 1000HZ jiffies, I hope the developers will make sure the system clock algorithm works accurately.

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