alt Hacker NewsIf you want you application to stay in memory, then make it explicitly with mlock()/mlockall().
Disabling swap will just moves pressere elsewhere: to code pages. And evicted code page is no better: full stall while kernel loads that page from disk.
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I think discussing it in a vacuum is pointless, it should depend on how much memory you have. You can have a swap on, but with a low `vm.swappiness` number.
Disabling swap disables loading a process' binary to memory? Or do you mean that evicted code pages will need to get loaded from disk every time.
While I've seen systems grinding to a halt due to evicting code pages, the idea that disabling swap distributes load between code pages and data pages makes no sense to me. Data pages are also disk backed, so they could also be evicted at any time. Why would data pages be written to swap if they came fron the disk in the first place?
So that only leaves anonymous data pages, i.e., regular data in memory, that could be swapped. Ok but you're not easing the load on code pages, those still get evicted during memory pressure whether you have swap or not.
FYI: This `delamon` account seems to be meat proxying us. Just relaying garbage AI answers without understanding his own words. Doubt he's ever used mlock himself for anything.
His reply below was presumably killed by mods for doing this: https://news.ycombinator.com/item?id=49970841