Amit

@system_monarch Thank you for sharing these concepts in depth and concisely! Much appreciated!!

1) Load Balancing: x.com/system_monarch… 2) CDN: x.com/system_monarch… 3) Caching: x.com/system_monarch… 4) Cache Invalidation: x.com/system_monarch… 5) Rate Limiting: x.com/system_monarch… 6) API Gateway: x.com/system_monarch… 7) CAP Theorem: x.com/system_monarch… 8) Sharding: x.com/system_monarch… 9) Replication: x.com/system_monarch… 10) Partitioning: x.com/system_monarch… 11) Queues: x.com/system_monarch… 12) Microservices: x.com/system_monarch… 13) Microservices Vs Monoliths: x.com/system_monarch… 14) Fault Tolerance: x.com/system_monarch… 15) Database Scaling: x.com/system_monarch… 16) Service Discovery: x.com/system_monarch… 17) Consistency models: x.com/system_monarch… 18) Eventual Consistency: x.com/system_monarch… 19) Distributed Transactions: x.com/system_monarch… 20) Leader Election: x.com/system_monarch… 21) Horizontal vs Vertical Scaling: x.com/system_monarch… 22) Back of the Envelope Estimation: x.com/system_monarch… 23) Idempotency, Data Latency & Finale: x.com/system_monarch…

A month ago, I told everyone: "I've been a backend Engineer for 12+ years. Today, I'm a Principal Engineer at Atlassian. I've designed systems that handle millions of requests. Sat on both sides of system design interviews. Reviewed more architecture docs than I can count. Starting today, I'm breaking down the fundamentals of scaling for the next 25 days. If you're learning system design bookmark this thread, you're going to get a lot of learning from this." FYI, the series has concluded. Here are all the concepts, please bookmark, share, learn and the most important build from the learnings you get. Also, if you have any ideas on what you'd like to see from me, please let me know, any other series or concepts to be broken down.

@system_monarch Thank you Puneet for such a great series! In Lease based leadership, how typically a leader renews its lease? Would it need another component for it? What if leader and that component are unfortunately partitioned allowing leader to renew lease but still disconnected from rest?

Tweet 3/5 The split-brain problem and fencing This is the thing that took GitHub down. And it's the most dangerous failure mode in leader election. How split-brain happens: 1. Leader (Node A) is running fine 2. Network partition isolates Node A from the rest of the cluster 3. Nodes B, C, D, E can't hear Node A's heartbeats 4. They elect a new leader: Node B 5. But Node A is still alive. It doesn't know it's been replaced. It still thinks it's the leader. Now you have two leaders. Both accepting writes. Both making decisions. Clients connected to Node A write one thing. Clients connected to Node B write something different. Data diverges. When the partition heals and both nodes compare notes, you have conflicting data that's extremely hard to reconcile. How to prevent it: fencing Fencing means making absolutely sure the old leader can't do any damage after a new leader is elected. Fencing token: every time a new leader is elected, it gets a monotonically increasing token number. Any operation includes this token. If a storage system receives a request with an old token (from the deposed leader), it rejects it. The old leader's requests simply stop working. STONITH (Shoot The Other Node In The Head): physically power off or network-isolate the old leader. Sounds extreme. It is. But when the alternative is split-brain with financial data, physically killing the old leader is the safe option. Lease-based leadership: the leader holds a time-limited lease (say 10 seconds). It must renew the lease before it expires. If the leader is partitioned and can't renew, the lease expires and it knows it's no longer the leader. It stops accepting writes voluntarily. This is what most cloud-native systems use. It's simpler than fencing tokens and handles most cases. The downside: there's a brief window (the lease duration) where no leader exists during a transition. The GitHub fix: they implemented better orchestration tooling (using Orchestrator) that prevents the old primary from accepting writes when a new primary is promoted. Essentially automated fencing.

GitHub, October 2018. A network partition lasted 43 seconds and caused a 24 hour outage. The MySQL cluster panicked. Elected a new primary. The old primary didn't get the memo. Two leaders. Both accepting writes. Both convinced they were the source of truth. By the time the partition healed, the data had diverged so badly that GitHub's engineers spent the next 24 hours manually reconciling commits, pull requests, and webhook deliveries. Here's why this happened 👇

@surnell sir, how long would this be open? There is name mismatch for me with Aadhar, I have submitted for its correction. But there is address change as well (same constituency). So hopefully, I will be able to address both within time (if there is any time limit for it).

#Karnataka Fill out your #SIR form right on your mobile! It did not take me more than 4 minutes for submitting revisions online. Visit voters.eci.gov.in. Use approproate Forms and Submit via Aadhaar e-Sign. Let us weed out illegal voters #OurVoteOurRight

@JoeyMannarino Very well deserved...congrats Britts! Wishing you many many more..looking at your policies it wont be surprised that you all will be swimming among them like grey ducks very soon...!!

Imagine being born in Manchester as a white British person and having to live amongst this shit. Who the hell allowed this to happen?

@skm_utd @NewsAlgebraIND wake up dumbo...its not 2006 anymore...or did you loose ability to count properly...

@NewsAlgebraIND Of course he trusts India since they have their puppets ruling us

US SENATOR : "When I travel to China, I leave my phone in Washington instead of taking it with me. But when I travel to India, I bring this phone with me. That shows how much I trust India. I can't do the same in China"

@NewsAlgebraIND .....and he thinks we trust him or US....🤣🤣 seriously, clowntown america at its majestic display..!!

@BesuraTaansane Indeed, iyer's PR worked around the clock for this success. They exceeded all expectations to make this happen portraying GG in bad light. But looks like iyer is hell bent on proving them wrong! Sooner the better..!!

So chhapri Shreyas Iyer made an embarrassing debut as captain of Indian T20I team with a humiliating 34 run loss to minnows Ireland - the first ever lossy to Ireland in any format He failed both as a captain and batter scoring just 3 of 7 balls #IndvsIre

@CRED_club Really..!!?!! We must be thankful that you haven't enabled retina scan or face recognition...........yet!!

touching...🥲

@namma_vjy No siree, you don't live in desert, we at C V Raman nagar, HAL live..! Only rains are in watery eyes after seeing different VCs.. :(

4.20PM: Finally Rains 🌧️☔ reach the Gotti Desert 🏜️ Typical Monsoon rains #BengaluruRains

@namma_vjy So Gottigere has officially lost its crown as "Bangalore Desert". That now belongs to HAL - C V Raman Nagar :( Enjoy..!!

1.00PM: Passing Monsoon Rains 🌧️☔ in Gottigere. Love these Calm Rain. #BengaluruRains

@BrianMcDonaldIE You are saying as if its for the first time this is said and you are hearing it for very first time! Isn't this a consistent stance by India ever since this issue started? OR has EU taken leaf out of its Orange Buffoon master's playbook to play dumb? Or are both dumb really?

Indian Foreign Minister Subrahmanyam Jaishankar says India bought Russian oil after 2022 partly because Washington secretly asked for it. “At that time, the US specifically asked India to buy Russian oil to stabilise the oil market,” Jaishankar said at an event in Finland, according to Bloomberg. Jaishankar also rejected the moralising around Russian oil purchases. “Let’s not pretend that this is about some great principles,” he said. “I don’t think hypocrisy is appropriate here.” .

@alexstubb @DrSJaishankar Its so brave of you to keep smiling and pretending all is well like your Orange Buffoon master despite being shown mirror time and again to reflect your own dirty faces..bravo..!

Thank you for participating in the Kultaranta Talks, @DrSJaishankar. It was good to hear your views on the situation in the Middle East and Russia’s war of aggression in Ukraine. India is an influential player on the world stage. Honoured to have Dr. Jaishankar here!

@finland227 @alexstubb @DrSJaishankar Why? Is Ukraine a damsel in distress and world is bound to save it from....hmmm....Russia, in a game that NATO started...? How does this math work unless you and your Orange master think rest of world as your foot-mat?

@alexstubb @DrSJaishankar India is helping Russians buy their oil, but what help has India given to Ukraine?

@pierceboggan Another token guzzler in making..!

Native diagramming capabilities coming soon to the GitHub Copilot app!

@HondaCarIndia Have had a few really nice, memorable trips in Elevate! It is fun & I love to drive it. But similar to @Brijesh23382433, due to some "good" experiences I pray that I don't get to visit service center for anything. How can everyone of them be bad while product is so awesome?

The best adventures don't come with directions. With bold styling and adventure-ready accessories, the Honda Elevate ADV is built to take you beyond the usual. #HondaElevateADV #HondaCarsIndia #BoldMove

@surnell When PM felicitated different workers (few times at-least), 'they' called it 'tamasha' & what not...But this is most noble thing only raga can perform & it shouldn't be called as staged performance, should it? Anyway, upgrade from eating at random, poor house in OWN constituency.

Let us make him PM of Auto Driver Association

@alpha_defense 'This' and no one will ask existential questions, they may mock at best..! But with ISRO....

Jeff Bezos' Blue Origin's New Glenn Rocket Explodes During Test

@namma_vjy Its sad that trees fall in much awaited TS but worst that fallen trees aren't replaced, the place stays vacant for a while, becomes dump yard after and eventually gets concretized..

Post TS ⛈️⚡🌩️ in Bengaluru. Update from Traffic Department. #BengaluruRains

@namma_vjy Latest Crown jewel of Bengaluru desert of 2026, #HAL is receiving TS rains now..much relieved..!

🛑 TS CAUTION FOR BENGALURU Friends there is high possibility for TS rains in Bengaluru this evening between [6.00PM to 10.00PM[. Take adequate care and escape Bengaluru Traffic Jam :) Note: Avoid staying under trees during TS rains. Its dangerous. #BengaluruRains

@surnell Isn't she the one having unbeaten track record of screwing up careers of politicians whoever she met or interviewed??

Saar. Yaake Saar. Karnataka CM issue settled. Best wishes for next time now