Elasticsearch Hot Shard Problem: When One Node Does All the Work
5 data nodes but one is at 100% CPU. Uneven routing keys create hot shards. I show how to detect skew and fix it with routing strategies.
#indexing
3 posts
UUIDv4 vs ULID vs TSID: Impact on PostgreSQL B-Tree Indexes After 100M Records
Random UUIDs as Primary Keys cause index bloat and random I/O. Benchmark with specific numbers - index size, cache hit ratio, and WAL volume after 100M inserts.
The Index That Killed Write Performance: Losing PostgreSQL HOT Updates
Adding an index for performance made writes 10x slower. The counter-intuitive cause: the new index broke HOT updates, turning cheap in-place updates into full-row rewrites with massive bloat.