Change micro SD paths to memory mount paths - CUPS package

[davigre]

I want to write microSD card as less as possible and CUPS package uses the following path's by default (although can be changed):

/var/cache/cups
/var/log/cups
/var/run/cups
/var/run/cups/printcap
/var/spool/cups
/var/spool/cups/tmp

But I think this paths are pointing to micro SD card (except .'/var/log') (or not?)

root@pcduino3nano:/etc/cups# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/root 7.3G 1.1G 6.0G 16% /
devtmpfs 500M 0 500M 0% /dev
tmpfs 128M 212K 128M 1% /run
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 128M 0 128M 0% /run/shm
tmpfs 256M 0 256M 0% /tmp
ramlog-tmpfs 256M 2.2M 254M 1% /var/log

Which is the best strategy so this path's points to memory and Not to microSD? 

 

I propose changing the path''s to something like '/tmp/cups/...', But I need to 'mkdir /tmp/cups/...' in the boot process after 'mount' but before CUPS start, How can I make this? I found that can be done in '/etc/rc.local' file. Is this correct ?

 

Thank you.

[wildcat_paris]

@davigre

 

a first idea: tmpfs?

 

https://en.wikipedia.org/wiki/Tmpfs

https://insights.ubuntu.com/2016/01/20/data-driven-analysis-tmp-on-tmpfs/

 

also, being careful, you can "play" with soft links "ln -s directorysource directorylinked"

[tkaiser]

CUPS (at least when running on OS X) takes some special precautions regarding locations of temporary files (since CUPS showed some really horrible security flaws in the past). This should be considered when you try to adjust/relink paths.

 

I would try to 'solve' the problem in a different way:

• check fstab (commit interval)
• check filesystem activity vs. block device activity (maybe just to realize that most of CUPS' temporary files never get written to SD card?)
• buy quality SD cards and check the state of technology (they implement wear leveling so there's no reason to fear immediate wear out)
• since your board features SATA think about using a small SSD and put the rootfs on it

BTW: I do server stuff in the graphical industry for a living and it's always too funny when you have to work together with 'normal' IT professionals that start to snoop network traffic. They're immediately scared by the huge amount of data transferred between clients (usually OS X) and servers (Solaris/Linux). A single printjob exceeding 1 GB is quite normal but network professionals that are used to office environments already start to scream (in other words: spool files might get big so take care)