Not to stray too much off topic, but is any of this being communicated to the Linux kernel devs?
Even if we get the best of all worlds for SCALE[1] (i.e., FreeBSD-like ARC behavior + no more issues with swap or crippling slowdowns), I think Linux needs to do some serious rework of their memory management if simply using ZFS + a very high zfs_arc_max causes the system to needlessly swap to disk.
EDIT: To be more clear on this point, it’s silly that removing the very presence of swap allows the kernel to behave more sanely.
It’s like having a dog that tears up all your furniture and attacks your guests because you have a box of treats visibly set on the table. But then if you remove the box of treats from the house, your dog starts behaving properly. (Even though it always could have this entire time!)
It’s looking to be the case that we might have a longterm solution for SCALE soon, without sacrificing the benefits of the ARC.
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