igb driver hw.em.rxd hw.em.txd

[Dach Shong]

Hello.
My system FreeBSD 12.2 .
I have an igb network card.
Found out that the igb driver has merged with em.

Where are the system parameters?
hw.em.rxd="4096"
hw.em.txd="4096"

# sysctl hw.em.rxd
sysctl: unknown oid 'hw.em.rxd'

https://www.freebsd.org/cgi/man.cgi?query=em&apropos=0&sektion=4&manpath=FreeBSD+12.2-RELEASE&arch=default&format=html

*LOADER TUNABLES*
<https://www.freebsd.org/cgi/man.cgi?query=em&apropos=0&sektion=4&manpath=FreeBSD+12.2-RELEASE&arch=default&format=html#end>
     Tunables can be set at the	loader(8)
<https://www.freebsd.org/cgi/man.cgi?query=loader&sektion=8&apropos=0&manpath=FreeBSD+12.2-RELEASE>
prompt before	booting	the kernel or
     stored in loader.conf(5)
<https://www.freebsd.org/cgi/man.cgi?query=loader.conf&sektion=5&apropos=0&manpath=FreeBSD+12.2-RELEASE>.


 *hw.em.rxd*
	     Number of receive descriptors allocated by	the driver.  The de-
	     fault value is 1024 for adapters newer than 82547,	and 256	for
	     older ones.  The 82542 and	82543-based adapters can handle	up to
	     256 descriptors, while others can have up to 4096.

 *hw.em.txd*
	     Number of transmit	descriptors allocated by the driver.  The de-
	     fault value is 1024 for adapters newer than 82547,	and 256	for
	     older ones.  The 82542 and	82543-based adapters can handle	up to
	     256 descriptors, while others can have up to 4096.