Bug#773252: systemd-timesyncd syncs time about once per minute

[Jos van Wolput]

This issue is fixed by enabling hpet in GRUB_CMDLINE_LINUX="upgrade-from-grub-legacy vga=769 hpet=enable".
By default hpet is disabled.
Using hpet instead of acpi_pm as clocksource the interval now increases exponentially:

Dec 21 14:27:26 debian systemd-timesyncd[2663]: Using NTP server 202.112.29.82:123 (0.cn.pool.ntp.org).
Dec 21 14:27:26 debian systemd-timesyncd[2663]: interval/delta/delay/jitter/drift 32s/-0.083s/0.045s/0.000s/-411ppm
Dec 21 14:27:58 debian systemd-timesyncd[2663]: interval/delta/delay/jitter/drift 64s/+0.014s/0.044s/0.005s/-299ppm
Dec 21 14:29:02 debian systemd-timesyncd[2663]: interval/delta/delay/jitter/drift 128s/+0.020s/0.046s/0.013s/-222ppm
Dec 21 14:31:43 debian systemd-timesyncd[2663]: interval/delta/delay/jitter/drift 256s/+0.042s/0.048s/0.016s/-140ppm
Dec 21 14:35:59 debian systemd-timesyncd[2663]: interval/delta/delay/jitter/drift 512s/+0.041s/0.049s/0.018s/-100ppm
Dec 21 14:45:03 debian systemd-timesyncd[2663]: interval/delta/delay/jitter/drift 512s/+0.066s/0.049s/0.026s/-35ppm
Dec 21 14:54:08 debian systemd-timesyncd[2663]: interval/delta/delay/jitter/drift 1024s/+0.025s/0.044s/0.023s/-23ppm
Dec 21 15:11:44 debian systemd-timesyncd[2663]: interval/delta/delay/jitter/drift 2048s/+0.038s/0.046s/0.021s/-14ppm