Use the free command to inspect RAM and swap at a glance and spot pressure fast. 15.03.2026 | reading time: 2 min Want a fast snapshot of RAM and swap? Use the `free` command to see total, used, free, shared, buff/cache and available memory in one glance. Quick check Run this to inspect memory quickly: ```bash $ free -h total used free shared buff/cache available Mem: 15Gi 1.2Gi 9.0Gi 120Mi 4.8Gi 13Gi Swap: 2.0Gi 0B 2.0Gi ``` Columns in context Read the columns carefully: total is installed RAM, used is what the kernel reports as in use, free is currently unused, buff/cache are reclaimable kernel caches, and available estimates memory usable for new applications without swapping; prefer the `available` column over raw free when judging memory pressure and try `free -h --si` for SI units. Practical workflows Monitor a host with `watch -n1 free -h` to see trends; script quick checks for automation, for example `free -m | awk 'NR==2{print $7" MB"}'` to extract available memory for alerts, and use `free -t` to include totals when comparing multiple systems. Neighbors in the toolbox When deeper detail is needed, consult `vmstat` for IO and context switches, `top` or `htop` for per-process usage, and read `/proc/meminfo` directly for the raw kernel counters that `free` reports. Next step Keep exploring LINUX memory diagnostics and sharpen command-line skills; consider pursuing CompTIA Linux+ or LPIC-1, and use bitsandbytes.academy for intensive exam preparation. Join Bits & Bytes Academy First class LINUX exam preparation. utilities troubleshooting processes scripting infrastructure
