UCS - FI - N5k Actual speed v theoretical speed

[ronanphelan]

Hi All

Is anyone aware of a formula (or have their own) that can be applied to calculate the actual speed of a link?

e.g. 10gb Port Channel between Chassis and FI or 16gb FC Port Channel from FI to Nexus 5k, what it the actual throughput?

Or has anyone come across any whitepapers or tests conducted and published?

many thanks

[scotthan · Accepted solution]

There's some data here -> Cisco UCS Outperforms HP and IBM Blade Servers on East-West Latency

The links are going to perform at close to wire speed. There's always a little overhead for the packet passing, which is true for any vendor. It's hard to nail down any real numbers without real data flowing through the pipes. For UCS it's relatively easy to measure the utilization of the links. See Vallard Benincosa great blog post on how to get the metrics -> UCS Monitoring Part 1: Collecting and Analyzing UCSM Data | Vallard's Tech Notes

Most customers I've had do this exercise are "suprised" that their 10G links in production are 5-10% utilized.

[ronanphelan]

Thanks Scott

Appreciate it