Hibernate and suspend are different. I configure my laptop to suspend for 3 hours before hibernating. That means I can close the lid for lunch or a commute and instantly resume, but if I leave my laptop in my bag over a long weekend, the battery isn’t drained. Does it save much battery? Dunno. A few % over a few days maybe.
I just noticed Ubuntu removed the hibernate option some years ago, you can probably enable it if you really want to, but the default seems to be to only suspend to memory.
Remember read that power saved wasn’t a lot, there was the downside of disk usage, and there were some security concerns when using full disk encryption.
Don’t use Ubuntu, but are you sure it removed it and didn’t do the same thing windows does (i. e. hybrid suspend, where it does the same as hibernating, but then enters suspend, so if power is cut you still have your ram preserved)?
I believe the swap partition is also used when hibernating. So when you use hibernate you need at least equal swap space as memory size.
I thought most systems only used suspend to memory at this point, you don’t save a lot of power by turning the CPU off compared to deep sleep state.
Hibernate and suspend are different. I configure my laptop to suspend for 3 hours before hibernating. That means I can close the lid for lunch or a commute and instantly resume, but if I leave my laptop in my bag over a long weekend, the battery isn’t drained. Does it save much battery? Dunno. A few % over a few days maybe.
I just noticed Ubuntu removed the hibernate option some years ago, you can probably enable it if you really want to, but the default seems to be to only suspend to memory. Remember read that power saved wasn’t a lot, there was the downside of disk usage, and there were some security concerns when using full disk encryption.
Don’t use Ubuntu, but are you sure it removed it and didn’t do the same thing windows does (i. e. hybrid suspend, where it does the same as hibernating, but then enters suspend, so if power is cut you still have your ram preserved)?
Yes, the default is that you can’t hibernate to disk, I think they changed it back in the 2020 release.
You can add the needed packages, swap, configure grub, etc. if you want to use hibernate, but it’s not part of the default installation.
The point isn’t to save power, the point is that the laptop is completely off. You can even take out the battery if needed