root@OpenWrt:/tmp# opkg install openclash.ipk
Installing luci-app-openclash (0.45.06-beta) to root...
Collected errors:
* verify_pkg_installable: Only have 2460kb available on filesystem /overlay, pkg luci-app-openclash needs 3748
* opkg_install_cmd: Cannot install package luci-app-openclash.
root@OpenWrt:/tmp# df -h
Filesystem Size Used Available Use% Mounted on
/dev/root 3.3M 3.3M 0 100% /rom
tmpfs 59.6M 4.8M 54.7M 8% /tmp
/dev/mtdblock6 10.1M 7.7M 2.4M 76% /overlay
overlayfs:/overlay 10.1M 7.7M 2.4M 76% /
tmpfs 512.0K 0 512.0K 0% /dev
device: xiaomi wifi mini
im trying to install a ipk software but failed coz the space not enough, here's df details. this's 54.7M spare space, is it possiable to give to /overlay ? [noob question]
No. tmpfs is RAM - it is not persistent storage. This means everything will be erased from tmpfs when the system is rebooted or powered off.
What device are you using?
EDIT: looks like you've added your device to the original post...
you've got a USB port on that device -- look at setting up extroot using a thumb drive.
/tmp/ is backed by tmpfs, which defaults to half your RAM size - you don't have that much free space, that's just RAM and gone once you reboot. What you have is apparently a 16 MB flash device, of which ~6-6.5 MB are already used by plain OpenWrt and 7.7 MB of your remaining flash size (10.1 MB) by previously installed packages, leaving you with 2.4 MB free space.
It depends…
You can remove the packages previously (runtime-) installed by you, as only those reside in the overlay and will free up space again (removal of the parts coming with the OpenWrt firmware itself won't free up any space), but opkg won't really assist you with that (dependencies aren't known/ removed) - a factory reset tends to be the more sensible option.