Re: [Libguestfs] [PATCH v2] v2v/v2v.ml: Use larger request size for -o rhv-upload
On Mon, Feb 14, 2022 at 04:08:21PM +0000, Richard W.M. Jones wrote:
There is a limit on the number of parallel requests in flight
(nbdcopy --requests, default 64). This limits the implicit buffer to
max_requests * request_size. That's 16MB in the default
configuration. Quite small actually ...
https://gitlab.com/nbdkit/libnbd/-/blob/6725fa0e129f9a60d7b89707ef8604e0a...
I've managed to reproduce the problem locally now so I can try playing
with this limit.
Or rather, I thought I'd reproduced it, but after repeating the
test a few times it's just ordinary variability.
Anyhow I tried increasing the nbdcopy --requests parameter to 64->256
but it didn't change the speed (faster or slower).
Rich.
--
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