fping is S-L-O-W... this is the best run I had:

$ time /usr/local/sbin/fping -r1 -g 10.100.19.1/24 -a 2> /dev/null
10.100.19.1
10.100.19.50
10.100.19.85
10.100.19.87
10.100.19.200

real    0m18.816s
user    0m0.010s
sys    0m0.000s
[download]

Maybe I did something wrong, but I could only get it down to one retry, and the default sure isn't zero, despite the --help claim.

I tried Time-Slice Concurrent Ping with the modifications I posted in that thread and tuning the parameters (allow 254 outstanding pings, 1 second timeout), and this is what I get:

$ sudo time ./multiping.pl
Reply time for 10.100.19.1 - 3.007 seconds
Reply time for 10.100.19.50 - 3.000 seconds
Reply time for 10.100.19.85 - 2.994 seconds
Reply time for 10.100.19.87 - 2.993 seconds
Reply time for 10.100.19.200 - 2.971 seconds
PONG: 10.100.19.1
PONG: 10.100.19.50
PONG: 10.100.19.85
PONG: 10.100.19.87
PONG: 10.100.19.200
0.15user 0.02system 0:04.11elapsed 4%CPU (0avgtext+0avgdata 0maxreside
+nt)k
0inputs+0outputs (394major+191minor)pagefaults 0swaps
[download]

With this one, it's always less than 4.25 seconds, which is much more useful to me.

--isotope