LFS-PCC-DETACH(1)

📦 version 2.17.58, in ubuntu stonking

💅 LFS-PCC-DETACH(1) 💅

okay bestie, so this is a page from the Lustre User Utilities manual set, and honestly? it's giving housekeeping. it's giving "we need to talk about your cache."

🎀 NAME 🎀

lfs-pcc-detach, lfs-pcc-detach_fid — say bye-bye to specific files and yeet them out of PCC ✨

🦋 SYNOPSIS 🦋

lfs pcc detach [--keep|-k] FILE [...]
lfs pcc detach_fid [--keep|-k] {--mnt|-m MNTPATH} FID [...]

🌸 DESCRIPTION 🌸

so basically, you take a specified FILE or FID and you detach it from the persistent client cache. that's it. that's the whole plot. main character energy but for cache entries 💖

✨ OPTIONS ✨

  • -k, --keep — okay so by default, the detach command detaches FILE from PCC permanently and removes the PCC copy after detach. no take-backsies. BUT this option? this option only detaches the file in memory, and keeps the PCC copy chilling in cache 🫶. that means the detached file is allowed to be attached automatically at the next open, as long as the cached copy of the file is still valid. it's giving "we're on a break", not "we're over".
  • -m, --mnt — specify the Lustre client mountpoint for the file FID that's getting detached. don't skip this one, the FID needs to know where it lives 🏠

🌈 EXAMPLES 🌈

detach the file permanently from PCC. the cached file on PCC will be removed after detach. IO to the file will come to Lustre OSTs after this command:

$ lfs pcc detach /mnt/lustre/test

detach the file referenced by FID "0x200005348:0x101:0x0" from PCC permanently, and the cached file on PCC will be removed after detach:

$ lfs pcc detach_fid -m /mnt/lustre 0x200005348:0x101:0x0

detach the file "/mnt/lustre/test" from PCC. the client will try to attach this file again at the next open if the cached copy is still valid:

$ lfs pcc detach -k /mnt/lustre/test

detach the file referenced by FID "0x200000401:0x1:0x0" from PCC. the client will try to attach this file again at the next open if the cached copy is still valid:

$ lfs pcc detach_fid -k -m /mnt/lustre 0x200000401:0x1:0x0

👑 AVAILABILITY 👑

lfs pcc detach is part of the lustre(7) filesystem package since release 2.13.0. she's been around, she's established, she's iconic 💅

💜 SEE ALSO 💜

bestie reminder: plain detach means the cached copy is gone and IO goes back to the Lustre OSTs. add -k if you want it to re-attach itself later. choose wisely 😭

and that's the whole page, no cap 🧚 from the Lustre crew, dated 2026-03-19. go detach something responsibly, love u, bye 🎀💖

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