Re: [Libguestfs] nbdcpy: from scratch nbdcopy using io_uring
On Fri, Jun 25, 2021 at 02:16:51PM +0530, Abhay Raj Singh wrote:
> However 6 is probably too low - in nbdcopy we use 64.
I kept it low just to verify the system works in the way I intended it to.
> So you can
> open multiple TCP connections on each side and issue multiple
> commands in flight on each of those connections.
I will look into this, so we open multiple sockets hence get multiple
socket_fds which we can read from and write to?
Yes.
> The code looks very minimal at the moment. I'm not very
familiar with
> the fmt:: class.
It's just for formatting and output like printf.
>Does it successfully make a handshake to ‘nbdkit -o’
> yet?
I read in the protocol document https://github.com/NetworkBlockDevice/nbd/blob/
master/doc/proto.md#oldstyle-negotiation
that handshake is just about the server sending data to the client on accept,
I open a socket and connect then read the handshake, and with the data,
then populate NbdConnection variables. All this is done currently in the
constructor of NbdConnection synchronously. So I guess the answer
is yes.
[...]
command to run nbkit server
nbdkit data ' ( 0x55 0xAA )*2048 ' -o -f -p 1234
Yes this is good.
Another way to test it might be something like this:
nbdkit -v -o random 1G --run './src/nbdcpy --source \$port --destination
\$port'
(You could use other plugins instead of random, such as data,
sparse-random, memory, etc.)
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-top is 'top' for virtual machines. Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://people.redhat.com/~rjones/virt-top