Good morning!
In a recent blog post we explained how to tweak a simple UDP application to maximize throughput. This time we are going to optimize our UDP application for latency. Fighting with latency is a great excuse to discuss modern features of multiqueue NICs. Some of the techniques covered here are also discussed in the scaling.txt kernel document.
CC BY-SA 2.0 image by Xiaojun Deng
Our experiment will be setup up as follows:
Reading takes a long time, though, don’t you find? It takes such a long time to get from, say, page twenty-one to page thirty. I mean, first you’ve got page twenty-three, then page twenty-five, then page twenty-seven, then page twenty-nine, not to mention the even numbers. Then page thirty. Then you’ve got page thirty-one and page thirty-three — there’s no end to it. Luckily Animal Farm isn’t that long a novel. But novels . . . they’re all long, aren’t they. I mean, they’re all so long.
" Martin Amis, Money —This is the fourth and final blog post in the WLAN capacity planning series. Be sure to read the first, second, and third posts.
We all want high performing WLANs. In order to do that we must push Wi-Fi to its limits!
(Cue Scarface Theme, verse 1)…
Push it to the limit!
Walk along the perimeter edge
But don’t look up, just keep your head
And you’ll be finished
Survey to the limit!
Past the point of no bandwidth
You’ve reached the edge but still you gotta learn
How to build it
Hit the floor and double your pace
Laptop wide open like an engineer outta hell
And you crush the speed test
Going for the back of every room
Nothing gonna stop you
There’s no wall that strong
So close now, battery near the brink
So, push it!
We walk a fine line when designing wireless networks, attempting to push as many users and bandwidth through our APs as possible, ensuring adequate capacity is available to meet demand, while not overbuilding the network. But what are the limits and how do we know we’ve hit them? Or more importantly, how do we plan Continue reading
Just a note for future reference:
Space’s local database backups are kept in /var/cache/jboss/backups (Platform version 13.1R1)
You can retrieve these using WinSCP in SFTP mode. For some reason there’s a shell error when using SCP. This appears to have started happening since the bash shell vuln was discovered – although I’ve never applied Juniper’s bash patch to the system. Upgraded WinSCP to the latest, but no luck.
Just a note for future reference:
Space’s local database backups are kept in /var/cache/jboss/backups (Platform version 13.1R1)
You can retrieve these using WinSCP in SFTP mode. For some reason there’s a shell error when using SCP. This appears to have started happening since the bash shell vuln was discovered – although I’ve never applied Juniper’s bash patch to the system. Upgraded WinSCP to the latest, but no luck.
I’ve been writing and talking about the need for IT teams to reduce the lifecycle of infrastructure to 3 years. For this to happen, the following items: pay less for products so that money can be spent on projects to replace and upgrade pay less so that ROI can be achieved 3 years design so […]
The post Musing: Virtual Appliances and Shorter Lifecycles appeared first on EtherealMind.
At least a dozen engineers sent me emails or tweets mentioning Project Calico in the last few weeks – obviously the project is getting some real traction, so it was high time to look at what it’s all about.
TL&DR: Project Calico is yet another virtual networking implementation that’s a perfect fit for a particular use case, but falters when encountering the morass of edge cases.
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