The NOVA filesystem [LWN.net]

The NOVA filesystem

Posted Aug 5, 2017 12:09 UTC (Sat) by eSyr (guest, #112051)
Parent article: The NOVA filesystem

Is it better than tmpfs? If so, can tmpfs be transparently replaced with nova?

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The NOVA filesystem

Posted Aug 5, 2017 13:32 UTC (Sat) by dskoll (subscriber, #1630) [Link] (4 responses)

My understanding is that tmpfs will spill into swap space if necessary. That's clearly not something NOVA would want to do. So if you need that feature, then NOVA cannot replace tmpfs.

The NOVA filesystem

Posted Aug 6, 2017 12:17 UTC (Sun) by idra (subscriber, #36289) [Link] (3 responses)

Why would you ever touch swap? I already have to regularly systemctl mask tmp.mount to avoid useless tmp data sucking away precious RAM...

The NOVA filesystem

Posted Aug 6, 2017 21:25 UTC (Sun) by dskoll (subscriber, #1630) [Link] (2 responses)

tmpfs data doesn't suck away precious RAM. It uses the cache to store data and that memory is reclaimed if needed.

The NOVA filesystem

Posted Aug 10, 2017 15:23 UTC (Thu) by krakensden (guest, #72039) [Link] (1 responses)

I don't know how it's implemented, but my first bad experience with tmpfs /tmp was discovering that Vagrant wrote machine images there, and everything started behaving super poorly. Is it safe to use now with large files?

The NOVA filesystem

Posted Aug 10, 2017 15:31 UTC (Thu) by bof (subscriber, #110741) [Link]

tmpfs is totally usable with large files - as long as you have enough RAM to spare and don't have it go to swap.

I use tmpfs continuously on server VMs, with multi GB files and/or up to 80 GB in smaller files (precomputed mysql tables...) - always worked without any issues. However, these VMs don't have any swap configured (or even swap support in the kernel), so YMMV.