alt Hacker NewsFor GC enabled languages swap is universally bad. Some gc-pauses are indistinguishable from a system crash. It's a side effect on not having tightly specified memory limits.
I'd rather have applications be oom_killed than having them swap out, the former is rather obvious and demands action.
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Please read the article. The issue was caused by swapped out metadata being read in a critical section, not typical heap traversal shenanigans.
This is not exclusive to GC, any program that reads a rarely accessed piece of memory is vulnerable to this.
Run your process in a cgroup that's set to disallow swap, then. The rest of your system benefits from having swap. This was an easy and safe thing that required minimal convincing to roll out to production at my company.
If 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.