> From: Chris Murphy <lists@xxxxxxxxxxxxxxxxx> > Sent: Mon Jan 13 05:51:15 CET 2020 > To: <arch-general@xxxxxxxxxxxxx> > Subject: systemd-zram generator > > > Hi, > > swap-create@.service generator for zram devices > https://github.com/systemd/zram-generator > > zram: Compressed RAM based block devices > https://www.kernel.org/doc/Documentation/blockdev/zram.txt > > The gist is, if a configuration file exists, a /dev/zram0 device is > created during early boot and marks it for use by swap.target; so all > the existing systemd stuff to mkswap and swapon gets used. > > The nice thing is, very low overhead. RAM is not reserved for the > device, it's only consumed as needed. > > The generator could be installed by default, but without a > configuration file. In that case, it doesn't create a swap on zram > device, unless the user creates a configuration file. And at some > point, the distribution can decide to include a configuration file by > default. > > I'm thinking a useful yet conservative default would be to create a > device up to 1:1 with RAM, capping out around 2G-4G. That way small > RAM devices, like Pi's, get a pretty big zram device. And large RAM > devices just have a smallish swap for incidental usage. > > One issue (reported upstream in github) is getting priority supported. > I don't know whether it needs to be configurable, from the config > file. But it seems sane to have the generator set a high priority, so > that the zram device is used first, spilling over to a conventional > swap if the user creates ones. > > This is a project in rust. And I think once some of the issues get > worked out, it would be great if distributions can converge on this > implementation. > > Thanks, > > -- > Chris Murphy There are many tools to configure zram available, one is even in Arch Linux repos: https://www.archlinux.org/packages/community/any/systemd-swap/ I guess when/if systemd-zram generator will be part of systemd then distros will converge onto it. Yours sincerely G. K.
