I am running XUbuntu 16.04 with kernel 4.4.0-116-generic (but the same goes for earlier versions) and 16 GB of RAM. I am using a "traditional" hard drive (no SSD) and my swappiness is 0 (RAM is rarely full).
I have been experiencing the following with hibernation : hibernation proper takes less than 2 minutes, but resuming from it takes much, much more time until the applications are responsive (today it took more that 10 minutes to get to the light-locker prompt).
I do not think this is usable (it takes more time to resume from hibernation than booting to a fresh session and reopening the programs).
How can I improve performance ? Am I the only one experiencing these problems ?
True, memory usage right now is 8.8 GB, but what bugs me is the discrepancy between hibernating and resuming times. I understand from other questions that it may be because during hibernation, the kernel freezes all processes and dump the RAM en bloc to swap, while on resuming it just lets processes ask for their pages in swap.
Is this a valid explanation ? If so, why is it done so, as reading big blocks from a hard drives is faster than random accesses ? Can I configure hibernation to not proceed this way ? The question "Restoring in-memory/swapped page state on resume from hibernation" seems related, but I do not know enough of pages to really understand if what they do ("take note of the tags that label what pages are on disk and in RAM, then restore this exact state on resume") is useful and I also do not know how to do it.