2023-12-18 12:04:47

by Cedric Blancher

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Subject: Realtime NFSv4?

Good morning!

How feasible would be a realtime NFSv4, which can guarantee NFSv4
operations in a constant time manner suitable for realtime
applications (similar to XFS realtime support)?

Yes, I know NFSv4 uses TCP, which is a bit allergic to realtime, but
aside from that (there is always RTP), can the NFSv4 protocol and
Linux implementation be modified for constant time?

Ced

PS Credits go to Roland Mainz for pitching the idea
--
Cedric Blancher <[email protected]>
[https://plus.google.com/u/0/+CedricBlancher/]
Institute Pasteur


2023-12-19 04:38:59

by Christoph Hellwig

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Subject: Re: Realtime NFSv4?

On Mon, Dec 18, 2023 at 12:48:00PM +0100, Cedric Blancher wrote:
> Good morning!
>
> How feasible would be a realtime NFSv4, which can guarantee NFSv4
> operations in a constant time manner suitable for realtime
> applications (similar to XFS realtime support)?

The XFS realtime subvoume is grossly misnamed, it does not guarantee
anything at all. It just uses a separate, somewhat more predicatable
allocator.