Re: NFS Server performance

No confusion. The read and write buffer sizes would be above layer 3. VMware offers little ability to modify read and write sizes. It did inspire me to find this: https://kb.vmware.com/s/article/1007909

NFS.ReceiveBufferSize

This is the size of the receive buffer for NFS sockets. This value is chosen based on internal performance testing. VMware does not recommend adjusting this value.

NFS.SendBufferSize

The size of the send buffer for NFS sockets. This value is chosen based on internal performance testing. VMware does not recommend adjusting this value.

...

ESXi 6.0, 6.5, 6.7:
Default Net.TcpipHeapMax is 512MB. Default send/receive socket buffer size of NFS is 256K each. So each socket consumes ~512K+.For 256 shares, it would be ~128M. The default TCPIPheapMax is sufficient even for 256 mounts. Its not required to increase.

Also, the man page for mount_nfs implies -w is useful for UDP mounts. I have verified that this mount is using TCP.

-w writesize
Set the write data size to the specified value. Ditto the
comments w.r.t. the -r option, but using the "fragments dropped
after timeout" value on the server instead of the client. Note
that both the -r and -w options should only be used as a last
ditch effort at improving performance when mounting servers that
do not support TCP mounts.

-Steve S.

-----Original Message-----
From: owner-misc@openbsd.org <owner-misc@openbsd.org> On Behalf Of Carsten Reith
Sent: Wednesday, December 6, 2023 11:41 AM
To: misc@openbsd.org
Subject: Re: NFS Server performance

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Steven Surdock <ssurdock@engineered-net.com> writes:

> The client is VMWare ESXi, so my options are limited. I tried
> enabling jumbo frames (used 9000) and this made very little
> difference.
>

Is it possible that you confuse the network layers here ? Jumbo frames are layer 2, the read and write sizes referred to apply are layer 3. You can try to set them as suggested, indepently of the frame size.