@rkenmi - Search Results

CAP Patterns

The CAP Theorem dictates that only two of its three characteristics can be guaranteed at any given time. Intro to CAP Consistency Every read will be based off of the latest write Availability Every request will be given a response, although the response data might be stale Partition Tolerance It can handle network partitions or network failures MTV's The Real World If your service is in the cloud, the P in Partitioning has to always be accounted for.

December 16, 2020

PostgreSQL - a powerhouse relational database

... scalable - adding more memory, cpu cores, and disk space gives it a significant boost in capabilities. On average commodity hardware, we can expect the ballpark performance to be as follows: Read Performance Index reads can range from 10,000 TPS - 20,000 TPS per CPU core Complex join queries: Around 1,000 - 2,000 TPS Full table scan: This is naturally slow, but is especially egregious if the records cannot fit into memory Write Performance Single-table INSERT INTO: ~5,000 TPS per CPU core Single-table UPDATE (plus index updates): ~1,000 TPS per CPU core Multi-table/index writes from complex transactions: ~100 TPS Bulk operations: ~10,000 TPS Bottlenecks PostgreSQL performance on a single node will degrade if any of the following is true: Size of all data cannot be contained in memory Disk space being exceeded Disk I/O The write performance above is bounded by disk I/O constraints while writing to the WAL Complex joins or updates to multiple tables/indexes are always going to be a bottleneck If records exceed 10 million: Queries and joins start to stagnate Full text-search also starts to degrade ACID Guarantees PostgreSQL is widely known for its ACID properties - Atomicity, Consistency, Isolation, and Durability.

July 11, 2025

RDBMS Optimization

Indexing Probably the easiest tweak to implement. It can usually be done with one SQL command. However, an index should be made based on a good column. For example, if you are frequently querying your rows by timestamp, then the timestamp can be chosen for an index.

June 23, 2020

Web Development 101

... to this improvement. CPU cores nowadays are already multi-core, and core clock frequency has capped at around 3ghz for quite some time. You can expand your hard disk space and RAM, but even they have size limits.

November 9, 2017