Example of a bad cable - see the latency

[sfx2000]

Was doing some debug on the network, and saw this...

Swapped the cable out, and latency went down a fair about - thruput wasn't impacted that much, just a lot of 'jitter' on ping response to to the router and upstream...

cool..

 

[System Error Message]

are you measuring in micro seconds? It seems like the best latency you got is about the same as i get. I've seen LAN pings of 0.1 ms but have never managed to achieve it.

 

[sfx2000]

are you measuring in micro seconds? It seems like the best latency you got is about the same as i get. I've seen LAN pings of 0.1 ms but have never managed to achieve it.

Yes, the script does auto-range...

 

[sfx2000]

to one of my internal hosts - the previous graph was WAN side...

 

[sfx2000]

I've seen LAN pings of 0.1 ms but have never managed to achieve it

that's about as good as it can get with gigabit ethernet from what I've seen... not just in my little lab at the casa, but even in the data center with bigger pipes, first thought here is framing overhead..

 

[Deepcuts]

are you measuring in micro seconds? It seems like the best latency you got is about the same as i get. I've seen LAN pings of 0.1 ms but have never managed to achieve it.

From their website: Note that fping must be installed setuid root. It seems that older versions of fping report round trip times in 0.1 milliseconds instead of 1 milliseconds as advertised ... SmokePing tries to figure this out. It tells you when it starts ... let me know if it gets it wrong.

 

[sfx2000]

Looks fine to me...

sfx@blaster:~$ ping 192.168.100.1

PING 192.168.100.1 (192.168.100.1) 56(84) bytes of data.
64 bytes from 192.168.100.1: icmp_seq=1 ttl=63 time=0.624 ms
64 bytes from 192.168.100.1: icmp_seq=2 ttl=63 time=0.536 ms
64 bytes from 192.168.100.1: icmp_seq=3 ttl=63 time=0.575 ms
64 bytes from 192.168.100.1: icmp_seq=4 ttl=63 time=0.563 ms
64 bytes from 192.168.100.1: icmp_seq=5 ttl=63 time=0.584 ms
64 bytes from 192.168.100.1: icmp_seq=6 ttl=63 time=0.555 ms
64 bytes from 192.168.100.1: icmp_seq=7 ttl=63 time=0.590 ms

--- 192.168.100.1 ping statistics ---

7 packets transmitted, 7 received, 0% packet loss, time 5998ms
rtt min/avg/max/mdev = 0.536/0.575/0.624/0.031 ms

sfx@blaster:~$ sudo fping -C 5 -q -e 192.168.100.1

192.168.100.1 : 0.64 0.62 0.61 0.62 0.63

 

[System Error Message]

For ethernet LAN ping should be 300 microseconds or lower. If you're getting around 500 microseconds or higher it is likely something is being slow in your network. Some dedicated NICs integrated into the board such as marvell however may have a response time of around 500 microseconds.

 

[sfx2000]

For ethernet LAN ping should be 300 microseconds or lower. If you're getting around 500 microseconds or higher it is likely something is being slow in your network. Some dedicated NICs integrated into the board such as marvell however may have a response time of around 500 microseconds.

All my other items on the LAN are right around 250 uS or so - the target I chose was the Surboard cable modem, and that's the maintenance port on it that runs the embedded web server...

$fping -C 5 -q -e 192.168.1.50
192.168.1.50 : 0.31 0.23 0.24 0.26 0.27

$ping 192.168.1.50
PING 192.168.1.50 (192.168.1.50) 56(84) bytes of data.
64 bytes from 192.168.1.50: icmp_seq=1 ttl=64 time=0.238 ms
64 bytes from 192.168.1.50: icmp_seq=2 ttl=64 time=0.216 ms
64 bytes from 192.168.1.50: icmp_seq=3 ttl=64 time=0.186 ms
64 bytes from 192.168.1.50: icmp_seq=4 ttl=64 time=0.193 ms
64 bytes from 192.168.1.50: icmp_seq=5 ttl=64 time=0.223 ms

--- 192.168.1.50 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 3997ms
rtt min/avg/max/mdev = 0.186/0.211/0.238/0.021 ms