The document discusses gentle_unlink, a Perl script created by OGATA Tetsuji that slowly deletes files over time instead of immediately to avoid spikes in disk activity. It can delete files gradually in the background while the disk is idle. This helps improve performance and reduce wear when deleting large numbers of files at once, such as when removing old log files or database tables. The author recommends it as an alternative to commands like rm and truncate that delete files all at once.

1. OGATA Tetsuji (@xtetsuji)
2016/06/16 Gaiax
https://flic.kr/p/dQYonj

2. • / / OGATA Tetsuji
• @xtetsuji
• Blog: http://post.tetsuji.jp/
• RND

3. • 1 @ichigotake
•
• Perl
•

5. https://slas.la/xtetsuji/gentle_unlink

6. Qiita:Team

7. https://github.com/xtetsuji/encoreutils/blob/master/bin/gentle_unlink

10. du
• gentle_unlink
• du -sh DIR 104MB
• find DIR -type f

11. Twitter
https://twitter.com/koiwa/status/729524213703319552

12. rm -rf

13. •
GB
• MP3
time rm radio.mp3

14. •
• unlink
•

15. https://twitter.com/stc1988/status/736169921952894976

16. • Twitter

18. •
• ext4

19. • GB TB
•

20. https://flic.kr/p/96ETY

21. truncate
• truncate
•
• 1TB 1.8GB→1.6GB→…
•
gentle_unlink

22. http://qiita.com/ogataka50/items/5647106c784d293eea8d

23. MySQL DROP TABLE
• DROP TABLE
• truncate
• MySQL
•

24. $ ls -l foo.txt
-rw-r--r-- 1 ogata ogata 288 Jun 16 15:24 foo.txt
$ ln foo.txt bar.txt
$ ls -l foo.txt bar.txt
-rw-r--r-- 2 ogata ogata 288 Jun 16 15:24 bar.txt
-rw-r--r-- 2 ogata ogata 288 Jun 16 15:24 foo.txt
$ md5sum foo.txt bar.txt
0fe4005a0c4717efaad4c37b2de19d7b foo.txt
0fe4005a0c4717efaad4c37b2de19d7b bar.txt
$ rm foo.txt
$ ls -l bar.txt
-rw-r--r-- 1 ogata ogata 288 Jun 16 15:24 bar.txt$ ls -l foo.txt
-rw-r--r-- 1 ogata ogata 288 Jun 16 15:24 foo.txt
$ ln foo.txt bar.txt
$ ls -l foo.txt bar.txt
-rw-r--r-- 2 ogata ogata 288 Jun 16 15:24 bar.txt
-rw-r--r-- 2 ogata ogata 288 Jun 16 15:24 foo.txt
$ md5sum foo.txt bar.txt
0fe4005a0c4717efaad4c37b2de19d7b foo.txt
0fe4005a0c4717efaad4c37b2de19d7b bar.txt
$ rm foo.txt
$ ls -l bar.txt
-rw-r--r-- 1 ogata ogata 288 Jun 16 15:24 bar.txt

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• 2015 3 5 6 1
10
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• Foursquare
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• ← Realized!

29. 💦