[Samba] Low performance when using "server signing" = "mandatory"

[lists at zxt10d.de]

Am 16.10.2023 um 15:13 schrieb Adam Błaszczykowski via samba:
> Hello,
> I'm experiencing very slow read/write performance, about 20 MB/s, on Samba
> share when I configure the "server signing" option as "mandatory". Once I
> set "server signing" to "default", the read/write performance returns to
> average speed about 800 MB/s.
> I am using Samba 4.9.4 on server with Intel Xeon CPU E5-2690 0 @ 2.90GHz
> (32 threads) and 10 Gbit ethernet controller.
> I need to set "mandatory" value for security reasons, but the performance
> is unacceptable. How to solve this problem ?
> 
> Thank you.
> Adam Blaszczykowski

Maybe its related to the samba version ...?
4.9.4 is pretty old ...