How to set and understand fs.notify.max_user_watches
sysctl -w
writes kernel parameter values to the corresponding keys under /proc/sys
:
sudo sysctl -w fs.inotify.max_user_watches=12288
writes 12288
to /proc/sys/fs/inotify/max_user_watches
. (It’s not equivalent, it’s exactly that; interested readers can strace
it to see for themselves.)
sysctl -p
loads settings from a file, either /etc/sysctl.conf
(the default), or whatever file is specified after -p
.
The difference between both approaches, beyond the different sources of the parameters and values they write, is that -w
only changes the parameters until the next reboot, whereas values stored in /etc/sysctl.conf
will be applied again every time the system boots. My usual approach is to use -w
to test values, then once I’m sure the new settings are OK, write them to /etc/sysctl.conf
or a file under /etc/sysctl.d
(usually /etc/sysctl.d/local.conf
).
See the sysctl
and sysctl.conf
manual pages (man sysctl
and man sysctl.conf
on your system) for details.