Quote:
Originally Posted by ichnilatis
Excuse me. What is the sysclock?   |
It's the time your operative system reports.
On x86 computers, when the device is off, there's a chip that keeps ticking named Real Time Clock. That's usually called hwclock. When the system boots it reads the time from hwclock and saves it to sysclock. When the system poweroffs the sysclock is saved on hwclock.
On arm RTCs are not mandatory and some devices, like routers, IoT devices or plug computers, are designed without them and just pick current time from an online source using a protocol called ntp.
Mobile SoCs usually have a RTC integrated that's powered by the same battery that powers the entire unit. They usually keep the time just fine until the battery is removed or the battery is completely empty.