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Re: [Nbd] maximum size of a read/write request

--On 6 October 2011 12:53:55 +0200 Folkert van Heusden <folkert@...421...> wrote:

What is the maximum size of a read/write request? E.g. how much data can
be requested/transmitted using one read or write command?

I do not think there is a protocol limitation.

According to Paul, there is a kernel limitation on how much it will
in practice use, but I am not sure what that is nor whether it
in practice applies if something unconventional (e.g. a hypervisor)
is talking direct to the block layer.

nbd-server is written to handle arbitrary length requests (ok, I
have not checked operations longer than 2^31 bytes).

And can this be limited using a nbd-client command-line setting and/or
nbd protocol handshake?

Not currently.

Alex Bligh

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