this post was submitted on 07 Jul 2023
34 points (97.2% liked)

Selfhosted

39931 readers
463 users here now

A place to share alternatives to popular online services that can be self-hosted without giving up privacy or locking you into a service you don't control.

Rules:

  1. Be civil: we're here to support and learn from one another. Insults won't be tolerated. Flame wars are frowned upon.

  2. No spam posting.

  3. Posts have to be centered around self-hosting. There are other communities for discussing hardware or home computing. If it's not obvious why your post topic revolves around selfhosting, please include details to make it clear.

  4. Don't duplicate the full text of your blog or github here. Just post the link for folks to click.

  5. Submission headline should match the article title (don’t cherry-pick information from the title to fit your agenda).

  6. No trolling.

Resources:

Any issues on the community? Report it using the report flag.

Questions? DM the mods!

founded 1 year ago
MODERATORS
 

I've heard a lot of people say your swap should be 2x RAM.. but do I really need 32GB of swap?

you are viewing a single comment's thread
view the rest of the comments
[–] fiasco@possumpat.io 5 points 1 year ago* (last edited 1 year ago) (1 children)

I think it's better to think about what swap is, and the right answer might well be zero. If you try to allocate memory and there isn't any available, then existing stuff in memory is transferred to the swap file/partition. This is incredibly slow. If there isn't enough memory or swap available, then at least one process (one hopes the one that made the unfulfillable request for memory) is killed.

If you ever do start swapping memory to disk, your computer will grind to a halt.

Maybe someone will disagree with me, and if someone does I'm curious why, but unless you're in some sort of very high memory utilization situation, processes being killed is probably easier to deal with than the huge delays caused by swapping.

Edit: Didn't notice what community this was. Since it's a webserver, the answer requires some understanding of utilization. You might want to look into swap files rather than swap partitions, since I'm pretty sure they're easier to resize as conditions change.

[–] cmeerw@programming.dev 5 points 1 year ago

Unused (or very rarely used) memory can also be swapped out to make more memory available for the disk cache (in the hope that having more disk cache available will save more disk accesses than the (hopefully one-time) swap-out operation).