Back in the day when I was a technical architect and actually wrote code (yes, they did let me do that once) I got into a discussion with the rest of my team about the impact of our code on performance. I was saying white-space was evil because it can unnecessarily increase the number of packets necessary to transfer data. I wanted to go through the code (mostly JavaScript and HTML output) and reduce the white-space to make application response time better.

I was eventually overruled because, well, I just couldn't make the rest of the team understand the impact of our code on the network and performance and hey, one extra packet isn't going to really make a difference, is it?

Just as developers can adversely affect application performance because they don't always grok the network, network topology and connectivity rates can also affect application performance - and a whole lot more.

I stumbled across this great post on MySQL operational performance that describes this very scenario and thought it was awesome anecdotal evidence of the importance of understanding the network.
      Where is F5?

It's also important for network administrators to understand how the topology of their network - and its speeds and feeds - can have an adverse affect on a variety of tasks, not just application performance. The core of the problem in the aforementioned post was a simple uplink between two switches with a significantly lower throughput than esb-1 the rest of the network. A simple uplink reduced the total throughput from an anticipated 80 MB/second to 20 MB/second. That's huge, especially when you're talking about tossing around very, very, very large files.

Now if we were talking about a WAN link I'd mention WAN optimization because, well, there isn't much you can do about throughput limitations on WAN links. But this is a LAN, and while application acceleration technology could help with application performance in a similar scenario, the right answer here is simply to increase the uplink speed, or move the database servers all to the same switch with a higher speed uplink to the core switches/routers.

The network impacts everything because it delivers everything. Its toplogy and speeds and feeds are important for everyone to understand because it impacts the performance of ... everything. While I certainly think you should consider how F5 solutions can improve the performance, reliability, and security of your applications and infrastructure, sometimes the answer really is as simple as a bad cable ... or limited uplink speeds.

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