Package: zram-tools
Version: 0.3.2-1
Severity: important
Dear Maintainer,
zram module has max_comp_streams property since around 2011, and nowadays it is
(at least on x86/amd64) is autodetected to match the CPU core count.
Setting up multiple zram devices is inefficient even if each one is set to use
only one compression stream, but with default settings it will end up using
number of threads equal to square of the CPU core count (4 on dual-core, 16 on
quad-core, etc.)
Note that I don't have access to any ARM boards or other supported by Debian
platforms, so I cannot verify whether zram module has the same max_comp_streams
behavior there.
Also note that a more lightweight approach to setting up zram could use udev
rule instead, e.g. this is what I've been using on my systems:
KERNEL=="zram0", SUBSYSTEM=="block", DRIVER=="", ACTION=="add",
ATTR{initstate}=="0", PROGRAM="/bin/sh -c 'echo $(($(LANG=C free -k | grep -e
\"^Mem:\" | sed -e \"s/^Mem: *//\" -e \"s/ *.*//\")*2))KiB'",
ATTR{disksize}="$result", RUN+="/sbin/mkswap $env{DEVNAME}", TAG+="systemd"
-- System Information:
Debian Release: buster/sid
APT prefers unstable
APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386
Kernel: Linux 4.19.0-1-amd64 (SMP w/2 CPU cores)
Locale: LANG=uk_UA.UTF-8, LC_CTYPE=uk_UA.UTF-8 (charmap=UTF-8), LANGUAGE=en_US
(charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
Versions of packages zram-tools depends on:
ii bc 1.07.1-2+b1
zram-tools recommends no packages.
zram-tools suggests no packages.
-- Configuration Files:
/etc/default/zramswap changed [not included]
-- no debconf information
