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Save your disk, write files directly into RAM with /dev/shm

(hiandrewquinn.github.io)
62 points hiAndrewQuinn | 2 comments | 26 Jun 25 23:04 UTC | HN request time: 0.409s | source
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hackyhacky ◴[26 Jun 25 23:38 UTC] No.44392515[source]▶
Rather than re-write your scripts to store temp files into /dev/shm, you can just mount /tmp using the tmpfs file system and get the same benefit for all your programs. Some distros do this by default.

The relevant line from fstab is:

    tmpfs /tmp            tmpfs    noatime 0       2
Now any program that writes to /tmp will be writing to a RAM disk, thus sparing unnecessary wear on my SSD.
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hiAndrewQuinn ◴[26 Jun 25 23:40 UTC] No.44392526[source]▶
I do mention this offhand in the article: "The existence of /dev/shm is a boon for me mostly because it means I never have to worry about whether /tmp is really RAM-based again."
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frollogaston ◴[27 Jun 25 00:05 UTC] No.44392655[source]▶
"virtually every Unix system already has it mounted as a tmpfs by default" might be true if you say Linux instead, but Mac doesn't have /dev/shm
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1. loeg ◴[27 Jun 25 00:12 UTC] No.44392705[source]▶
I may misremember, but I think it's also common in the BSDs? (Whereas /var/tmp is persisted.)
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2. frollogaston ◴[27 Jun 25 22:44 UTC] No.44400967[source]▶
Yeah, Mac is probably the odd one out, but it's also maybe the most common Unix-based/Unix-like desktop OS. Anyway, both are POSIX, unlike Linux.