Hey, Fedora users with laptops with 8GB of RAM — I’m curious if our new compressed-ram default is helping you. After you have been running for a long time and have lots of browser tabs open and other apps running (like normal daily use for several days), can you please run
/sbin/zramctl
and post the results? Thanks!
If you’re running something other than GNOME, note that too please.
I’m on 16 GB, so I may not offer perfect insight, but when doing heavy virtualization tasks zram can really help, and is noticeably faster than swap. Besides that, I haven’t really noticed it
For clarity: Its biggest upside has been giving like 12 Gigs to a VM to compile something or whatever, and accidentally opening to many Firefox tabs. The slowdown is usually more graceful, and easier to remedy with zram.
Hi, I am using a 8gb machine but as I understand fedora doesnt make much use of ram. A gnome extension for cpu and mem usage shows about 16-20% use of ram even if cpu hits red. At my second pc with 16gb I get the same. Is dual boot and w10 show about 20% use of ram at all situtations and fc33 shows no more 20% use of ram. Maybe I dont get something but how to check the improvment of zram?
I don’t use my 8GB laptop enough to run into ram issues, but I recently filled up the ram and (4GB) zram swap on my 32GB system. It slowed down and nearly locked up at some point, probably due to heavy I/O when an automated borg backup started running, but never crashed. If I come across a similar situation again, I’ll post the results of /sbin/zramctl.
Previously with Ubuntu I would normally have weeks of uptime, rebooting around once a month. With Fedora having more frequent kernel updates, I typically go 7-10 days between reboots. Sometimes there are more than one kernel and software updates installed requiring reboots in that timeframe.
Thanks everyone! Next thing: if you found your zram swap to be heavily used, can you follow the steps here to increase the limit (as planned for F34) to see what effect that has?
$ sudo cp /lib/systemd/zram-generator.conf /etc/systemd/
$ sudo vi /etc/systemd/zram-generator.conf
/etc/systemd//zram-generator.conf:
# This config file enables a /dev/zram0 device with the default settings:
# — size — half of available RAM or 4GB, whichever is less
# — compression — most likely lzo-rle
#
# To disable, uninstall zram-generator-defaults or create empty
# /etc/systemd/zram-generator.conf file.
[zram0]
zram-fraction=1.0
max-zram-size=8192
It’s unfortunately much more complicated than that, because code can’t actually run from the compressed space; it has to be swapped in. So, basically when there is memory pressure (which is complicated), code that hasn’t run for a while gets pushed to the compressed area, making more room for active code. But when that now-compressed code needs to do something, it needs to come back out. When this hits disk (even SSD), it’s really, really painful. When it’s all in RAM (as with this feature) it is quite fast, but it’s still not free.