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Some thoughts on interviewing candidates

One of the most crucial parts of talent acquisition process is the initial round - where you decide if it is worth it to evaluate this candidate on the myriad parameters you might have. This post is not for veterans or hiring managers. This is for people in junior roles who are asked to conduct some parts of the interview process.

While I am still a bit low on the totem pole in my organisation - I do get to conduct these initial rounds and some more along the process. I have also observed other people (mostly my peers) in the org doing this. And I wanted to collect some thoughts I have regarding this.

1. Remember who is being evaluated and against what When you are in a position to evaluate someone else, it is only natural to mistake that the evaluation must be in some manner against yourself. Resist that temptation - you are looking at a potential team member and measuring them against yourself leads to nothing good. It will make you blind to some really good qualities of the candida…

High throughput Site to site VPN on commodity hardware - an adventure with Wireguard, bonding and ECMP

At work, I recently had an interesting challenge - we needed a high throughput site to site VPN between two of our co-located DCs. The existing one was not cutting it with the increasing demand for bandwidth every week. Normally I'd opt for the tried and tested IPsec tunnels using strongswan. One of my mentors had done this in the past - here is his own write-up. But I wanted to do something different this time. Enter Wireguard, the newest kid on the VPN block. What follows is a brief write up on the attempts to push decent amount of traffic on WG - enough to meet our needs.
Here comes the 'interesting' part of the challenge - One side only has 1G LAN - the final ISP uplink is 10G - but the server is only connected to a 1G switch. We need to push more than 1Gbps over the tunnel.  Here is how it looks:
+---------------------+                +----------------+
|                     |  Wireguard     |                |
|   Site A - 1G LAN   +------------->   Site B - 10G LAN|
|  …

A Tale of Apache and Two Congestion Control Algorithms in Linux (With a guest appearance by Openstack and cURL)

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Introduction:
The shortest intro would be these two cURL times - one for a bare metal server, and one for the Openstack VM - both running the same application, for a specific test URL.


Problem:

dnslookup: 0.109 | connect: 0.359 | appconnect: 0.000 | pretransfer: 0.359 | starttransfer: 0.624 | total: 6.739 | size: 710012
dnslookup: 0.016 | connect: 0.281 | appconnect: 0.000 | pretransfer: 0.281 | starttransfer: 0.531 | total: 6.958 | size: 710277
dnslookup: 0.000 | connect: 0.265 | appconnect: 0.000 | pretransfer: 0.265 | starttransfer: 0.530 | total: 5.351 | size: 709165

No problem:
dnslookup: 0.000 | connect: 0.265 | appconnect: 0.000 | pretransfer: 0.265 | starttransfer: 0.546 | total: 2.168 | size: 705631
dnslookup: 0.015 | connect: 0.281 | appconnect: 0.000 | pretransfer: 0.281 | starttransfer: 0.561 | total: 2.402 | size: 705354
dnslookup: 0.000 | connect: 0.265 | appconnect: 0.000 | pretransfer: 0.265 | starttransfer: 0.546 | total: 2.434 | size: 705485

For more details, read on.



Little b…

Review: This Is Going to Hurt: Secret Diaries of a Junior Doctor

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This Is Going to Hurt: Secret Diaries of a Junior Doctor by Adam Kay
My rating: 5 of 5 stars


Thanks for the recommendation @Gokila!

This is a brilliant, light heart-ed read.
However, most of the entries in this Diary will sound strange to the Indian reader. Surely Doctors are not this humble, are they? And what is this blasphemy - a patient conversing on equal terms with the doctor? But the other side is not so pretty either.

Here in India, we have a different kind of Patient - Doctor relationship than the rest of the world. We simultaneously adore them and loathe them. A significant portion of the population wants their off-springs to try their hand at being doctors - but an equally large portion of the population thinks the doctors conspire to put them through painful and expensive procedures to mint money. (Or worse, to "train" at their expense)

We all have read about doctors getting attacked by mobs because someone passed away and the crowd thought it was because the doc…