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Napoleon Hill Keys to Success: The 17 Principles of Personal Achievement, Napoleon Hill, ISBN: 978-0452272811
The 4-Hour Workweek: Escape 9-5, Live Anywhere, and Join the New Rich (Expanded and Updated), Timothy Ferriss, ISBN: 978-0307465351
The Fountainhead, Ayn Rand, ISBN: 0452273331
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mailto:olivier@olivierlanglois.net

Archives for: 2015

09/17/15

Permalink 11:33:38 pm, by lano1106, 224 words, 710 views   English (CA)
Categories: TCP/IP

Problem reach maximum transfer speed with 10Gbits Ethernet

I saw a very entertaining youtube video where the host has tested 10 Gbits Ethernet cards on a LAN to perform file transfers. He somehow could not reach the maximum theoritical transfer speed. Here is my explanation why and it is probably that simple:

I do not know what was the protocol underneath for the transfer but if it is TCP, there is something called the bandwidth-delay product that says that in order to keep the network pipe full, you need sufficient TCP send and receive buffers.

Let me show you how to compute that. RTT is basically given by ping. Lets assume worse case scenario with a RTT of 0.2 mSec. 10Gbit/sec is 1250MB/sec or 1,250,000,000 B/sec.

1,250,000,000 B/sec * 0.0002 sec = 250,000B or 250KB. Last time I have checked (I'm a Linux guy) default Windows TCP buffers size were something around 16KB or perhaps 64KB. These are the parameters that you would need to play with to get close to the 10GB/sec rates.

You can change the default value through the registry or on a per connection basis with the socket API.

If we take your maximum transfer rate in your video which was roughly about 360MB/sec and plug it in the bandwidth delay product formula, I get 72KB which is very close to 64KB. Pretty sure that this is your problem!

07/13/15

Permalink 10:44:16 am, by lano1106, 8 words, 1690 views   English (CA)
Categories: General

How a TRS-80 can help you dominating interviews

06/19/15

Permalink 12:28:33 pm, by lano1106, 9 words, 1476 views   English (CA)
Categories: Recommended books

Double Your Odds oF Getting Your Dream position in 14 DaYs or Less

My first book is now available:
http://getjobinterviewsfortechpros.com/
Hacking LinkedIn Formula

05/27/15

Permalink 08:55:53 am, by lano1106, 28 words, 1032 views   English (CA)
Categories: Recommended books

Improve 3 elements in your resume or your linkedin profile to double their effectiveness

free ebook where I show how to write a job description in a resume or for a linkedin profile for a MAXIMUM IMPACT.
http://getjobinterviewsfortechpros.com/free-job-description-advices-offer.html
how to write a job description in a resume or for a linkedin profile for a MAXIMUM IMPACT

Olivier Langlois's blog

I want you to find in this blog informations about C++ programming that I had a hard time to find in the first place on the web.

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