How I can send many radius requests/packets in parallel mode using radclient?

[work vlpl]

Hello,

I am trying to find limitation of my freeradius server setup. To do
that I use this command

`date && radclient  -r 1 -t 1 -q -c 350 -p 350 -f ./radpacket -s
172.31.10.73:1812 auth mysecret && date`

I am expecting that `-p` will try to send radius packets in parallel
mode. But it seems it does not work. Because, the stats after command
finished looks like this

`
Thu 21 Feb 17:54:00 UTC 2019
Packet summary:
Accepted      : 350
Rejected      : 0
Lost          : 0
Passed filter : 350
Failed filter : 0
Thu 21 Feb 17:54:39 UTC 2019
`
I use `date` command just to understand how much time it take to
process 350 requests. I am expecting that if packets were send in
parallel mode then processing time should be significant smaller.

Also I am reading this in comments from `radiusd.conf`

"When the server receives a packet, it places it onto an internal
queue, where the worker threads (configured above) pick it up for
processing.  The maximum size of that queue is given here. When the
queue is full, any new packets will be silently discarded."

But stats show me that 0 packets were lost.

I admit that maybe I use `raclient` in the wrong way. I used these emails

http://lists.freeradius.org/pipermail/freeradius-users/2016-February/082013.html
http://lists.freeradius.org/pipermail/freeradius-users/2007-November/023477.html

and man pages as guides how to use radclient to send packets in
parallel mode. So I don't understand what I am missing, and looking
how I can send many radius packets in parallel mode. Can somebody help
me with this?