Gossip protocol : Machines at water cooler

Close resemblance to how epidemics spread. But in our case it is a communication protocol.

– Involves pair wise inter process interaction
– After interaction, state of one of two interacting agent changes.
– It may so happen that the interaction fails between the processes.
– Cost of interaction is deemed negligible.
– Peers for inter process communication are selected randomly.
– There may be duplication in the message being gossiped, i.e. Both the agents were already aware of the messages being gossiped.

Gossip protocol

 

 

 

 

 

 

 

 

 

 

Type of Gossips
– Information dissemination
The piece of information needs to diseminated and the above protocol is used for the same. Gossips can either be periodic (no event based trigger) or on the basis of event based trigger.
– Anti-entropy Protocol :
The gossip happens and is used to make sure that there is no diff between the set of information two agents have.
– Aggregate computation –
The protocol can also be used to compute aggregates w.r.t to agent statistics. e.g. which agent have lowest health, best health, total of some resources. The nodes can be arranged in tree like structure for gossip.

The gossip protocol is widely used to check liveliness and heartbeat monitoring e.g. Cassandra, Dynamo db uses some variant of gossip protocol for the same.

 

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Gossip protocol : Machines at water cooler

Some things distributed

Howdy,

I was having a conversation recently at work, it was some work related topic and during that conversation, I had a realization that, at work, there are many things that we take for granted which function as building blocks for distributed systems, but are not at all obvious to everyone. I have been working in space of distributed systems for last 4 and a half years and have been blessed to be working with some of the sharpest minds in the industry. I truly mean sharpest, because some times I get inferiority  complex while talking to them. But I also do believe that I have done okay and have learned a lot in past years. I have been thinking a lot to summarize some of the lessons that I learnt, either from literature or on the job, so that somebody like me, who is starting out can read these blogs before heading out to the faulty world of distributed systems.
I will be submitting some posts in foreseeable future, which hopefully readers (whatever teeny tiny set I have) will find useful.

Before you start pointing out, yes, this is obviously a light hearted reference to similar named blog by Werner Vogels.

Some things distributed

Firefox and the Google Docs

I used to have Chrome as my primary browser and used to play around with Firefox once in a while to check out what’s new. I have always wanted to switch to ff want of better privacy setting but never did that because chrome was a lot better in terms of usability than ff in almost every way.

A few months back, Firefox released quantum (It is first named version in the long history of numbered firefox versions), tried it out and never went back to chrome. It was hands down better than chrome in terms of experience or so I thought.

A few days ago, I discovered that google docs copy/paste functionality did not work in firefox and google doc was unusable because of that. I was angry as well since I assumed it to be a deliberate attempt on Google’s part to make it unworkable with certain browsers. Turned out, I was wrong (and google did nothing wrong here) and there was a so-called “privacy protection” switch which was set to disallow clipboard reading by websites.

There is always an ongoing battle between convenience and privacy, I get that and I respect that. But if I do not think the above one was warranted protection since there is no way a not so technical person will be able to make it work and hence will switch back to chrome. By trying to go for 100% privacy protection, we lost the 99% protection that we were getting earlier (don’t get hung up on the numbers, made up).

In case you are trying to make google docs (or Gmail) copy/paste functionality work, here is how you can do it :

1. Go to about:config

2. Accept the warranty void warning.

3. Find the property : dom.event.clipboardevents.enabled and set it to true

If you haven’t tried the firefox out yet, I urge you to give it a try. It is as good as it is claimed to be.

Firefox and the Google Docs

2018 Reading list

Last year my score was 11 books but I am gonna aim a little higher this year (52: 1 per week). The first quarter of this year is quarter of books and running.

I generally divide the books into two categories – Fruits and Vegetables. I try to read them in equal proportions.

Followings books are the ones that I am gonna plan for next three months.

Vegetables :

  1. Zero to One
  2. Elon Musk: Inventing the Future
  3. The Innovators
  4. Einstein: His Life and Universe
  5. The Subtle Art of Not Giving a F*ck
  6. The 7 Habits of Highly Effective People
  7. The Design of Everyday Things

Fruits :

  1. 2001: A Space Odyssey(Space Odyssey, #1)
  2. Zero Hour (Expeditionary Force Book, #5)
  3. The Count of Monte Cristo
  4. The Man Who Knew Too Much
  5. Murder on the Orient Express (Hercule Poirot, #10) 
  6. Red Rising (Red Rising, #1)
  7. Golden Son (Red Rising, #2)
  8. Morning Star (Red Rising, #3)

I have struck the ones that I have finished reading.

2018 Reading list

Updates!

So, After posting the 5k every day run plan and trying to follow up on it, I figured there was not enough rest time for the body to recover since I am not used to running that much. I moved the running pattern to alternate days and I have ran 8 times till now and timing is shown in a chronological order showing how much time I took in each run. One of the photo shows double timing, and that was the day I did a 10k in around 76.30 Minutes (fastest for me) 🙂

 

Screen Shot 2017-11-04 at 10.50.21 PM.pngBut I have also been walking a lot, even on the rest days. Also, for month of october, My fitbit stats were :

  • 447,899 steps
  • 166 floors
  • 300.39 km
  • 110,821 calories
  • Lost 2.6 kg.

Out of 300km,  I ran 55 km.

Pretty cool , no ? 🙂

It was a pretty good month according

Updates!

Happiness and pursuit of happiness

I have contemplated long enough that what is it that brings happiness to us. I always felt a hole once I got placed after the college. The whole machinery for excitement just fell apart. I think it is the pursuit or the journey that gives more pleasure than the destination itself. The destination is always a temporary stop, so that we can move forward. I found that other people also the same thought and we should be creating out own quest. Quest that, are not easy but, are humanly possible. Quest that fill rage in you. Quests that make you feel better. Quests that you thought you couldn’t do. I have been thinking about it quite a while and Came up with following quest (I am calling this quest – Phoenix Challenge).

For next 30days, I am going to do the following :

  • 5km Running alternative days
  • 100 gm protein everyday.

This is going to require atleast a 1 hour of commitment everyday. Let us see how it goes. Interesting time 🙂

Also, It will be interesting to record a pic here to see if there are any noticeable changes after the month :

IMG_4253

Inspired by :

  1. http://rockingfor30days.com/
  2. https://medium.com/@emilykathrynrudow/i-ran-10km-everyday-for-31-days-straight-9b0584adc46f
Happiness and pursuit of happiness