[Samba] Samba share for HPC environment.

[Jeremy Allison]

On Mon, May 24, 2021 at 02:27:51PM -0300, Daniel Lopes de Carvalho wrote:
>Hi Jeremy, how are you doing?
>
>We are a petroleum engineering research lab. We work specifically with
>reservoir simulation and we have this HPC to do this job for us.
>
>There are some studie case that a user needs to simulate 100, 200 or 500
>cases at once. And these simulations take place in parallel, having an
>intense reading and writing operation.
>
>Samba is installed in the headnode of this HPC, but the storage is in
>another dedicated server and they are connected by NFS mount in an
>infiniband network (100Gbps). The clients (users desktops) are connected to
>headnode with a gigabit network.

Using NFS here isn't a great idea if you can avoid it.
NFSv3 or NFSv4 mount ? I'm assuming this is the Linux
kernel NFS client ? What Linux distro, what kernel version ?

>There are not many symptoms and after a certain time of running these
>simulations, Windows returns this error (An unexpected network error
>occurred) without giving details. In the Windows event logs there is also
>not much to investigate too. The error appears to be a momentary network
>outage.

Network outage between clients and headnode, or between headnode
and infiniband NFS server ?

>Some searches on Google have returned that it may be a Windows problem with
>UAC. But I haven't investigated it in depth yet.
>
>I thought that Samba could have a specific configuration for these intense
>uses of reading and writing, so I decided to write to you and ask for some
>advice.
>
>Thanks and best regards

I'd certainly advise using io_uring on Samba (presuming
the headnode is a supported version of the Linux kernel).

That should help performance-wise, but I'll need more
info to be able to help more.