Find which tmpfs instances are active, inspect their options and size, and act on them from the shell. 22.11.2025 | reading time: 3 min tmpfs is a memory-backed filesystem that often holds runtime files and temporary data; learn to locate every mounted tmpfs, read its options and usage, and take action from the command line. Quick discovery Run a single pipeline to list mounted tmpfs filesystems and read their options; do this now to see what consumes volatile storage on your host. Examples you can run ```bash $ mount | grep tmpfs tmpfs on /run type tmpfs (rw,nosuid,nodev,mode=755) tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev) tmpfs on /tmp type tmpfs (rw,nosuid,nodev,size=1G) $ findmnt -t tmpfs TARGET SOURCE FSTYPE OPTIONS /run tmpfs tmpfs rw,nosuid,nodev,mode=755 /dev/shm tmpfs tmpfs rw,nosuid,nodev /tmp tmpfs tmpfs rw,nosuid,nodev,size=1G $ df -hT -t tmpfs Filesystem Type Size Used Avail Use% Mounted on tmpfs tmpfs 1.0G 12M 988M 2% /tmp ``` Inspect raw kernel view Check the kernel's record with one command to avoid userland formatting: `cat /proc/mounts | grep tmpfs` will show the same mounts and options exactly as the kernel reports them. Change size or options on the fly If a tmpfs needs a larger allocation, remount it with new options; for example run `sudo mount -o remount,size=2G /tmp` to increase /tmp to two gigabytes without unmounting and losing data. Persistent mounts and best practices To make tmpfs persistent across boots, add an /etc/fstab entry like `tmpfs /tmp tmpfs defaults,size=1G 0 0`; prefer explicit size= and mode= values and avoid mounting writable tmpfs for sensitive binaries unless you understand the risk. Related commands in everyday work Use `findmnt` for structured output, `df` for usage statistics, and follow up with `ls -l` on the mount point (for example `/dev/shm`) to validate permissions and modes. Final thoughts Checking tmpfs mounts keeps surprises out of memory and swap, and lets the administrator balance speed versus memory usage; if you want to go deeper, practice these commands and consider formal Linux certification like CompTIA Linux+ or LPIC-1 with intensive exam prep at bitsandbytes.academy. Join Bits & Bytes Academy First class LINUX exam preparation. filesystem utilities troubleshooting storage
