On Wed, 25 Nov 2020 at 08:18, Giles Orr <gilesorr@gmail.com> wrote:
A few days after upgrading the last of my machines from Fedora 32 to 33, I noticed my main machine has acquired a new disk:
NAME SIZE FSTYPE LABEL MOUNTPOINT zram0 4G [SWAP]
I didn't set that up, and I don't think it was there on F32. So the OS has, without asking, co-opted 1/4 of my 16G of RAM to use as swap space. This system has an SSD, so when I initially set it up (Fedora 27), I made a conscious decision to go without swap space. I rarely push the limits of 16G.
But now I'm in the situation that I have only 12G of RAM, so the system will become memory-starved earlier ... and what will it do? It will go to swap. Which is RAM anyway. How does this help? To me this seems like adding complexity without adding utility.
Can someone please explain A) if I'm correct about this behaviour in the first place, and B) why it's useful? Thanks.
Hugh, this machine was an upgrade from Fedora 32. I guess the decision was made to go with the new default rather than ask questions during the upgrade. Thanks Hugh, Mauro, Dave for the info - and my apologies, I did zero research before turning to the list. Not my usual behaviour, I promise - I guess I was peeved because it was so unexpected. I assumed right out the gate that the statement "4G" meant it was using 4G of RAM. As has been pointed out, it's not allocated until it's used, and it's compressed - so even when full it'll usually only use 2G of RAM. After having read about it some, it sounds like it's mostly a win. -- Giles https://www.gilesorr.com/ gilesorr@gmail.com