https://akshatsharma.xyz hi, my name is Akshat Sharma en Sun, 08 Mar 2026 08:35:39 +0000 https://akshatsharma.xyz/posts/i-am-not-writing-enough/ I have recently been seeing a lot of posts talking about how “You are not writing enough”. There’s book clubs reading “Writing for developers”, people tweeting everyday about how writing has... Sat, 15 Feb 2025 00:00:00 +0000 https://akshatsharma.xyz/posts/i-am-not-writing-enough/ https://akshatsharma.xyz/posts/generalized-isolation-levels/ Personal notes on Generalized Isolation Level Definitions What are isolation levels? SQL Isolation levels(part of ACID) - Introduced to increase performance By improving concurrency Standardized? ANSI... Tue, 03 Sep 2024 00:00:00 +0000 https://akshatsharma.xyz/posts/generalized-isolation-levels/ https://akshatsharma.xyz/posts/cockroachdb/ These are my personal notes on CockroachDB paper CockroachDB: What is it? CockroachDB is a scalable geo-distributed SQL DBMS. Built using global OLTP workloads in mind with high availability and stron... Sat, 03 Aug 2024 00:00:00 +0000 https://akshatsharma.xyz/posts/cockroachdb/ https://akshatsharma.xyz/posts/experience_mongo_gen_ai_hackathon/ Last week, me and my team, http418, won the MongoDB Gen AI Hackathon. We created a tool called “tiktokify” which can automatically generate a small 30 second highlight clip from a video using clev... Sun, 14 Apr 2024 00:00:00 +0000 https://akshatsharma.xyz/posts/experience_mongo_gen_ai_hackathon/ https://akshatsharma.xyz/posts/22-web3/ Notes Bittorrent Bittorrent is already a decentralized file sharing platform. How does bittorrent work? When a client receives a .torrent file, it uses the DHT embedded inside the .torrent file to con... Mon, 27 Nov 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/22-web3/ https://akshatsharma.xyz/posts/21-bft-membership/ Notes Byzantine protocols can be used to increase the throughput of the blockchain but byzantine protocols work only with a closed membership model. Need to define an open membership model for BFT pro... Mon, 20 Nov 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/21-bft-membership/ https://akshatsharma.xyz/posts/20-permissioned-chain/ Notes After Bitcoin, other coins started popping up- Litecoin(using its hashing algo) only allowed mining using GPUs or CPUs. Monero(using its hashing algo) only allowed mining using CPUs. Ethereum al... Wed, 15 Nov 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/20-permissioned-chain/ https://akshatsharma.xyz/posts/19-proof-of-work/ Notes Bitcoin Reasoning for making bitcoin Anonymous Decentralized money system No trust in the government money system How does this work in a no trust environment? Use asymmetric encryption scheme l... Mon, 13 Nov 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/19-proof-of-work/ https://akshatsharma.xyz/posts/18-critique-of-ansi-sql-isolation-levels/ Notes Types of locks - Write lock Read lock Predicate lock - Lock where multiple rows are locked for reads(WHERE clause) All of these locks are long locks(Meaning all are acquired first and then all a... Wed, 08 Nov 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/18-critique-of-ansi-sql-isolation-levels/ https://akshatsharma.xyz/posts/ssh-permissions/ How To Set Correct SSH Directory Permissions in Linux Set Correct SSH Directory Permissions in Linux If you ever encounter errors while trying to SSH into a server, you can set correct ssh directory p... Tue, 07 Nov 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/ssh-permissions/ https://akshatsharma.xyz/posts/17-percolator/ Notes Bigtable doesn’t support multi-row/multi-table transactions. Why does Google need multi-table transactions? Removing duplicates(Multiple URLs may lead to the same website), calculation of page... Mon, 06 Nov 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/17-percolator/ https://akshatsharma.xyz/posts/16-spanner/ Notes Two strategies for implementing deadlock prevention used in 2-phase locking Wound wait - Force the lock to release from another transaction Wait die - Wait for lock to be released or die https:/... Wed, 01 Nov 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/16-spanner/ https://akshatsharma.xyz/posts/15-serializability-and-transactions/ Important Reading to help understand: https://jepsen.io/consistency Notes A - Atomicity (All or nothing of a transaction) C - Consistency (Consistent with the constraints on database tables) I - Isola... Mon, 30 Oct 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/15-serializability-and-transactions/ https://akshatsharma.xyz/posts/14-fork-join-consistency/ Notes Causal consistency and logical timestamps Logical Timestamps(Lamport timestamps) don’t imply causal consistency [13) Causal Consistency, COPS#Causal]({{< ref “13) Causal Consistency, COPS#ca... Wed, 25 Oct 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/14-fork-join-consistency/ https://akshatsharma.xyz/posts/13-causal-consistency-cops/ Notes Requirements for consistencies Linearizability Global ordering Completion to Invocation globally Sequential Global ordering Completion to Invocation per client Causal Completion to invocation pe... Mon, 23 Oct 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/13-causal-consistency-cops/ https://akshatsharma.xyz/posts/12-eventual-consistency/ Notes Dynamo is similar to a Distributed Hash Table meaning it uses consistent hashing. Dynamo is called a zero-hop DHT because each node has enough information about the whole consistent hashing ring... Wed, 18 Oct 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/12-eventual-consistency/ https://akshatsharma.xyz/posts/11-linearizability/ Notes Consistency is a spectrum with weak to strong levels. GFS/Eventual consistency is an example of weak consistency. Linearizability is an example of strong consistency. Consistency can be defined ... Mon, 16 Oct 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/11-linearizability/ https://akshatsharma.xyz/posts/10-byzantine-failures/ Readings - Practical Byzantine Fault Tolerance.pdf Byzantine PAXOS.pdf Notes What can be potential byzantine failures? Wrong replies which cannot be detected Halt consensus(same as crash so not really... Wed, 04 Oct 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/10-byzantine-failures/ https://akshatsharma.xyz/posts/9-mongodb-replication/ Notes Background Already existing scheme used db query for replication Replication scheme was in such a way that any follower could query any other follower Due to this when they tried to implement RA... Mon, 02 Oct 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/9-mongodb-replication/ https://akshatsharma.xyz/posts/8-paxos-made-live/ Notes Runs in 2 phases - Phase 1 - get a promise from majority of servers Phase 2 - get a majority of servers to commit Two important rules Two numbers should be used to track the system Highest seen ... Wed, 27 Sep 2023 00:00:00 +0000 https://akshatsharma.xyz/posts/8-paxos-made-live/