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ZRAM is amazing for cloud VMs which typically have strict disk IOPS limits which means any significant swap usage is going to destroy IO performance or even lock the system. ZRAM w/o swap completely prevents this IO condition and is much faster than disk swap anyway.

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Shouldn't a cloud VM have swap disabled by default if it's using networked block storage? It is on AWS at least.

Azure provides what they call "Azure Temporary disk" at typically /dev/sdb for most instance sizes; it's *not encrypted* and it's ephemeral, but is garanteed to be co-located (at least rack-level) with your CPUs.

Linux generally gets very squirrely when it's in a low-memory state. I think it's a bit safer to turn swappiness down and use a small swapfile and/or zram just to keep it from getting completely bricked up. That way you're sacrificing IO for a few seconds/minutes to intervene.

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