is swap useful?

[sinshiva]

a couple asuswrt-merlin revisions ago, i setup a 256mb swap partition (sda2) on my sdcard. initially, it actually had about 7mb of data in it, but ever since it pretty much just sat at 0/256. when i upgraded, i never re-enabled it. just curious if people are seeing any use out of it, perhaps those that are using their router as a media server, etc?

anybody have any recommendations for or against swap? (besides wearing out the sdcard, thanks)

[edit/] re-enabled it so i can watch it some more; via /jffs/scripts/post-mount [/edit]

[edit/] after testing a samba transfer, i'm now seeing a whopping 2mb of swap usage, most i'd seen in a while. dunno if it's related

 

[josh.zyman]

It's always good to have swap, and the unwritten rule of maximum swap size is twice the size of RAM if you have less than 4GB RAM or max 8GB swap if you have more than 4GB RAM.

If you use minidlna and the location of the database is in /tmp, swap is a good idea to have.

I have activated 1GB of swap on my RT-AC68U and never seen it to use more than 30MB.

Here is the tutorial I read to turn swap on my router: https://mydevtutorials.wordpress.com/2014/01/10/how-to-activate-swap-on-asus-rt-ac68u-router/

 

[RMerlin]

Swap is only useful if you run services that might be more memory-intensive, such as a Bittorrent client. For just basic routing it's useless - the 256 MB RAM on-board is more than enough for this.