Interface throughput

[c170719811]

Hi,

in tengiga interface (e.g. SFP+ 10GBASE-SR), the nominal throughput of 10 Gbps has to be considered as sum of RX and TX bits or 10 Gbps in RX and 10 Gbps in TX?

Considering the following whre RXBS+TXBS = 8.8 Gbps, the interface is near saturation or not?

Interface IHQ IQD OHQ OQD RXBS RXPS TXBS TXPS TRTL
-----------------------------------------------------------------------------------------------------------------

Te0/1/0 0 0 0 69 5806904000 716054 3072682000 643219 0

[kubn2]

Hi,

No, 10Gb/s means that you can have 10Gb/s of RX and 10Gb/s of TX in the same time so in the sum of 20Gb/s. Your interface still have plenty of room to "grow".

[c170719811]

Hi kubn2, thanks for your reply.

The interface is used for a 10 Gbps AWS Direct Connect.

We see packet loss as soon as Te0/1/0 throughput reach 9 Gbps (TX+Rx).

Platform used is cisco ASR1001-X (1NG), with the following license:

asr#show platform hardware throughput level
The current throughput level is 10000000 kb/s

Any idea for packet loss?

[kubn2]

Do you have some shapers policy that might drop traffic? WRED can drop traffic earlier to avoid congestion. Do you see drop on router interface or earlier? Maybe your ISP have some problem with throughput? Did you checked CPU usage on ASR? Is it high?

[Joseph W. Doherty]

Two possible causes come to mind.

First, when you look at interface loads, they are averages over time.  By default, the load average is over 5 minutes.  The minimum (I believe) can be set to 30 seconds.  Even at 30 seconds, bursts came exceed interface capability during milliseconds, possibly resulting in drops.  Check interfaces for ingress and/or (especially) egress drops.

Second, it appears you may have a platform throughput limit of 10 Gbps.  If so, that counts all traffic passing across the router, although (I believe) in only one direction from all interfaces.  Sum up all your interfaces' ingress bandwidth.  If that exceeds 10g, likely you'll find the sum of all the interfaces' egress bandwidth doesn't exceed 10g.

To clarify, on the same device, one interface's RX often becomes the sum of other interface TX.

[Reza Sharifi]

Hi,

The 1001-X out of the box support 2.5 Gig of throughput. You can upgrade to up to 20Gig. See link, table-5

https://www.cisco.com/c/en/us/products/collateral/routers/asr-1000-series-aggregation-services-routers/datasheet-c78-731632.html

Also, if this is used for AWS direct connect, are you connecting directly to an AWS transit gateway or using a provider (layer-2) for transit? If you are using a provider for transit, you may want to make sure their device can handle 10Gig as well.

HTH