LSMTree
A Log-Structured Merge-tree (LSM tree) is a write-optimized data structure that batches writes in memory and flushes them sequentially to disk as immutable sorted files, periodically merging (compacting) those files to control read cost and reclaim space.
15 resources across 2 libraries
Glossary Terms(4)
LSM Tree
A Log-Structured Merge-tree (LSM tree) is a write-optimized data structure that batches writes in memory and flushes them sequentially to disk as immutable sor…
Column-Family Store
A column-family store is a type of NoSQL database that groups related columns into named 'column families' within a row, storing and retrieving data by row key…
Wide-Column Database
A wide-column database is a NoSQL database that stores data in tables where rows can have a very large and variable number of columns, organized into column fa…
OLAP (Online Analytical Processing)
OLAP (Online Analytical Processing) refers to database systems and workloads optimized for complex analytical queries — aggregations, multidimensional analysis…
Interview Questions(11)
What is a Bloom Filter and How Do Databases Use It?
A Bloom filter is a compact, probabilistic data structure that tests whether an element is possibly in a set or definitely not in it, letting a database quickl…
What is an LSM-Tree and How Does it Handle Writes?
A Log-Structured Merge-tree (LSM-tree) is a storage engine design that turns random writes into fast sequential appends by first buffering writes in an in-memo…
What is Write Amplification and Why Does it Matter?
Write amplification is the ratio between the amount of data actually written to physical storage and the amount of data the application logically intended to w…
How to Design a Distributed Key-Value Store
A distributed key-value store is designed by partitioning keys across nodes with consistent hashing, replicating each key to N nodes for fault tolerance, and c…
How Do You Design for Read-Heavy vs Write-Heavy Systems?
Read-heavy systems are optimized by aggressively caching and replicating data close to readers so most requests never touch the primary store, while write-heav…
How Does a Write-Ahead Log Relate to an LSM-Tree?
A write-ahead log provides crash durability for a single write, while an LSM-tree is the broader storage engine architecture that uses that WAL alongside an in…
What is Write Amplification and Why Does It Matter for Storage Engines?
Write amplification is the phenomenon where a single logical write from an application triggers a much larger amount of physical data actually written to durab…
What is Read Amplification in Storage Engines?
Read amplification is the ratio between the amount of data a storage engine actually reads from disk and the amount of data the application logically requested…
What is Space Amplification in Storage Engines?
Space amplification is the ratio between the actual disk space a storage engine consumes and the size of the logical, deduplicated data it is meant to represen…
What is a Log-Structured Merge (LSM) Tree?
A log-structured merge (LSM) tree is a write-optimized storage data structure that buffers writes in an in-memory sorted table and periodically flushes them as…
B-Tree vs LSM-Tree Storage: Which Should You Choose?
B-trees update data in place with balanced, sorted disk pages that favor fast, low-amplification reads, while LSM-trees buffer writes in memory and flush them…