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Hosting Operations

Risk: safe

Summarize Cache File Ages

A cache tree is using many inodes and you need to see file age distribution before deciding on a retention threshold.

Command

find /lab/disk-inode-cleanup/var/cache/app -xdev -type f -printf '%TY-%Tm-%Td\n' | sort | uniq -c

Before you run this

Risk: safe. Do not use file age alone for application-owned caches that have their own invalidation or lock semantics.

Expected output

Counts of cache files grouped by date.

System impact

Nothing changes. The command groups cache files by modification date.

Recovery / rollback: no state is changed.

When to use it

Use before age-based cache cleanup so the cutoff is based on the actual file population.

When not to use it

Do not use file age alone for application-owned caches that have their own invalidation or lock semantics.

Watch this command run

Example output from a temporary Linux lab

This example uses disposable sample files and sanitized output so you can inspect the shape of the result before touching a real system.

demo@lab:~$

$ find /work/disk-inode-cleanup/var/cache/app -xdev -type f -printf '%TY-%Tm-%Td\n' | sort | uniq -c

    160 2026-06-26

$ find /work/disk-inode-cleanup/var/cache/app -xdev -type f -printf '%h\n' | sort | uniq -c | sort -nr

    120 /work/disk-inode-cleanup/var/cache/app/shards/a
     40 /work/disk-inode-cleanup/var/cache/app/shards/b
View reproducible demo details

This page shows the sanitized shell transcript and the setup steps needed to reproduce the example.

Lab setup steps

  1. find /lab/disk-inode-cleanup/var/cache/app -xdev -type f -printf '%TY-%Tm-%Td\n' | sort | uniq -c
  2. find /lab/disk-inode-cleanup/var/cache/app -xdev -type f -printf '%h\n' | sort | uniq -c | sort -nr

next steps

Related commands

Hosting Operations Risk: safe

Find Directories Burning Inodes

Inode cleanup starts by finding the directory with too many files.

find /lab/disk-inode-cleanup/var/cache/app -xdev -type f -printf '%h\n' | sort | uniq -c | sort -nr | head
Hosting Operations Risk: safe

Preview Old Temp Files Before Deleting

The safe version of cleanup is a candidate list first.

find /lab/disk-inode-cleanup/var/tmp/uploads -xdev -type f -mtime +7 -printf '%TY-%Tm-%Td %10s %p\n' | sort
Hosting Operations Risk: safe

Rank Old Cleanup Candidates by Size

The oldest file is not always the file that buys back meaningful space.

find /lab/disk-inode-cleanup/var -xdev -type f -mtime +7 -printf '%s %TY-%Tm-%Td %p\n' | sort -nr | head
Hosting Operations Risk: safe

Review Log Files Before Cleanup

Before truncating logs, prove which log files are large and how old they are.

find /lab/disk-inode-cleanup/var/log -xdev -type f -printf '%10s %TY-%Tm-%Td %p\n' | sort -nr
Hosting Operations Risk: safe

Exclude the Current Release from Cleanup

Release cleanup should prove what current points to before listing old directories.

current=$(readlink -f /lab/disk-inode-cleanup/home/deploy/current); find /lab/disk-inode-cleanup/home/deploy/releases -mindepth 1 -maxdepth 1 -type d ! -samefile "$current" -printf '%TY-%Tm-%Td %p\n' | sort
Study mapping

Use this as independent command practice: read the notes, predict the output, then compare it with the example before using a real shell.

  • lpic1:103-gnu-unix-commands
  • lpic1:104-filesystems-permissions-fhs
  • lfcs:essential-commands
  • lfcs:operations-deployment
  • lfcs:services-logs
  • lfcs:storage
  • linuxplus:automation-scripting
  • linuxplus:provisional
  • linuxplus:system-management
  • risk:read-only

Useful for

  • LPIC-1 style command-line practice
  • LFCS style performance tasks
  • Linux+ style troubleshooting review

Independent study support only. No affiliation, endorsement, exam dumps, or real exam questions.