Apache Cassandra

Understanding the CAP Theorem and Cassandra

Cassandra's Vector Search: Unlocking Semantic Understanding

Cassandra 5.0 New Features

Vector search + storage-attached indexes + UCS + trie index.

Cassandra Backup + Restore

Snapshots, incremental, PITR patterns. Restore procedures.

Cassandra Backups

How Cassandra backup works: nodetool snapshot, incremental backups, and offsite backup strategies.

Cassandra BATCH architecture

Deep-dive on Cassandra BATCH: coordinator load, batchlog table, logged vs unlogged, single-partition atomicity, and the async-concurrency pattern for …

Batch Statements

LOGGED batches != transactions. Unlogged for atomicity within partition.

Cassandra bloom filters -- skipping SSTables that can't have the row

Deep-dive on Cassandra bloom filters: the multi-SSTable read problem, probabilistic set-membership, the no-false-negatives property (guaranteed absenc…

Bloom Filters

Per-SSTable Bloom filter. False positive rate tuning.

Cassandra's CAP Trade-offs in Practice

What AP actually means when you turn the knobs.

Cassandra Clustering

How clustering columns order rows within a partition, enable range queries, and affect storage.

Cassandra commit log architecture

Deep-dive on the Cassandra commit log: sequential append-ahead-of-memtable durability, fixed-size segments and rollover, periodic vs batch sync trade-…

Cassandra Compaction

The three main compaction strategies in Cassandra and how to choose based on workload.

Cassandra Compaction Strategies

STCS vs LCS vs TWCS and when each one bites.

Cassandra compaction strategies -- STCS, LCS, and TWCS

Deep-dive on Cassandra compaction strategies: the LSM SSTable-accumulation problem, STCS (size-tiered, write-optimized), LCS (leveled, read-optimized)…

Cassandra Consistency Levels

How consistency levels (ONE, QUORUM, ALL, LOCAL_*) trade availability vs consistency per read/write.

Cassandra consistency levels

Deep-dive on Cassandra's tunable consistency: coordinators and per-request CLs, R+W>RF overlap mat…

Consistency Levels

Per-query CL. Trade latency + availability + consistency. Concrete recommendations.

Cassandra counters architecture

Deep-dive on Cassandra counters: coordinator behavior, read-before-write, shard IDs for idempotency, consistency, and limitations.

Counter Columns

Distributed counters. Special semantics. Common pitfalls.

Cassandra Data Model

How Cassandra's data model works: partition keys distribute data, clustering keys order within partition, and why you design tabl…

Cassandra Data Modeling Basics

Query-first design and the partition-key contract.

Cassandra: Distributed Systems Lessons

Cassandra distributed systems lessons.

Cassandra Gossip

Nodes learn about each other via gossip. Phi accrual failure detector.

Cassandra Hinted Handoff Architecture in Depth

A 2500-word walkthrough of Cassandra hinted handoff: coordinator stores hints, TTL, delivery, replay, hint storage, relationship to repair.

JVM + GC Tuning for Cassandra

G1GC standard. Heap sizing. Escape STW pauses.

Cassandra JVM Tuning in 2026

G1, ZGC, heap sizing, and what changed in recent releases.

Lightweight Transactions (LWT)

IF NOT EXISTS + IF conditions. Paxos-based. Cost 4x normal write.

Cassandra LWT architecture

Deep-dive on Cassandra Lightweight Transactions: Paxos rounds, coordinator, SERIAL consistency, contention penalty, alternatives.

Cassandra LWT: When and How

Lightweight transactions explained without the marketing.

Cassandra materialized view architecture

Deep-dive on Cassandra materialized views: base table, view definition, coordinator maintenance, consistency, rebuild, alternatives.

Materialized Views

Auto-maintained denormalized tables. Known issues. Avoid in production.

Cassandra memtable flush architecture

Deep-dive on Cassandra's write path: durability via the append-only commitlog, speed via the in-memory memtable, and the flus…

Migrating from Relational DB to Cassandra

Data modeling shift. Common pitfalls in migration.

Cassandra Multi-DC Architecture in Depth

A 2500-word walkthrough of Cassandra multi-DC: DC-aware driver, LOCAL_QUORUM, NetworkTopologyStrategy, async replication, hinted handoff, repair, DR.

Multi-DC Cassandra Deployment

NetworkTopologyStrategy + LOCAL_QUORUM. Latency + consistency.

Cassandra Multi-DC Design

Replication topology, network keyspace, and DC-aware reads.

Multi-DC Cassandra Topology

Two-region Cassandra deployment. NetworkTopologyStrategy, rack awareness, LOCAL_QUORUM. Full topology with rack layout, snitch config, and replication…

Cassandra Multi-Datacenter

How Cassandra's multi-datacenter deployment enables geographic distribution with local reads and writes.

Cassandra Operational Metrics

JMX + Prometheus. Which metrics matter most.

Cassandra operations architecture

Deep-dive on Cassandra ops: rolling restart, node replacement, bootstrap, repair, capacity, GC/JVM tuning, compaction, upgrade.

Cassandra Pagination

Server-side paging via state cookie. Client patterns.

Cassandra paging -- fetching large result sets safely

Deep-dive on Cassandra paging: the large-result problem, page size, the paging-state cursor, driver auto-paging, cursors-not-offsets (efficient at any…

Partition Key Design

Right key = fast + balanced. Wrong key = hot partitions + OOM. Concrete patterns.

Cassandra Partitioning

How Cassandra distributes partitions via consistent hashing, virtual nodes, and the Murmur3 partitioner.

Prepared Statements

Compile once, execute many. Cache locally. Avoid CQL parsing overhead.

Cassandra Query Tracing

TRACING ON to diagnose slow queries. Understand output.

Cassandra Read Path

How Cassandra reads consult MemTable, row cache, bloom filters, and SSTables to reconstruct current row state.

Cassandra Read Path End-to-End

Detailed walkthrough of a Cassandra read: coordinator selection, replica lookup, MemTable + SSTable merge, Bloom filter, key cache, block cache, read …

Cassandra read repair architecture

Deep-dive on Cassandra read repair: the coordinator compares a full read against replica digests, and on a mismatch reconciles by cell timestamp under…

Read Repair + Hinted Handoff

Automatic consistency mechanisms. When they help vs limits.

Cassandra Repair

How Cassandra repair reconciles inconsistent replicas via Merkle trees, and how to schedule repair operations.

Cassandra repair architecture

Deep-dive on Cassandra repair: Merkle trees, streaming sessions, full vs incremental, subrange, preview mode, Reaper scheduling, and gc_grace.

Cassandra Repair

Full vs incremental vs subrange. Reaper. Getting repair right.

Cassandra Repair in 2026

Full vs incremental vs subrange repair — what to actually run.

Replica Placement Strategies

SimpleStrategy vs NetworkTopologyStrategy. Multi-DC configuration.

Cassandra replication architecture

Deep-dive on Cassandra replication: RF, SimpleStrategy vs NetworkTopologyStrategy, consistency levels, hinted handoff, read repair.

Cassandra Storage-Attached Indexing (SAI)

Deep-dive on Cassandra SAI: per-SSTable indexes built at flush time and merged through compaction, index components for text, numeric range, and vecto…

Scaling Cassandra Up + Down

Add nodes: bootstrap. Remove: decommission or removenode. Ops runbook.

Cassandra secondary indexes -- querying beyond the partition key

Deep-dive on Cassandra secondary indexes: the non-key-query problem, the local (per-node) 2i, scatter-gather across all nodes for global queries, card…

Secondary Indexes

Native SASI, 2i. Not for high-cardinality. Anti-patterns to avoid.

Cassandra Secondary Index Traps

Why most secondary indexes are wrong and what to do instead.

Cassandra snitch architecture

Deep-dive on the Cassandra snitch: why topology awareness is the precondition for surviving rack and datacenter failures, the snitch implementations (…

Cassandra speculative retry architecture

Deep-dive on Cassandra speculative retry: per-table latency tracking, PERCENTILE vs fixed vs ALWAYS/NONE policies, the coordinator hedge to a spare re…

Cassandra SSTable Format Architecture in Depth

A 2500-word walkthrough of Cassandra SSTable format: Data, Index, Summary, Filter, Statistics, CompressionInfo, TOC/Digest, and read path.

Cassandra Storage Engine

How writes traverse memory + disk. Understand this to diagnose write pain.

Cassandra bootstrap architecture

Deep-dive on Cassandra node bootstrap: token allocation algorithms versus random selection, range calculation and snitch-aware source selection, the z…

Streaming Operations

How data moves between nodes. Rate limits. Common issues.

Cassandra for Time-Series

Bucketing, TWCS, and TTLs for the workload Cassandra is best at.

Token Ring + Virtual Nodes (vnodes)

How data distributes. Old single-token vs modern vnodes. Choice matters.

Cassandra tombstones

Deep-dive on Cassandra tombstones: deletes as markers in append-only LSM, gc_grace_seconds retention and compaction removal, read-scan impact and quer…

Tombstones

How deletes work + why they cause slow queries. Prevention + remediation.

Cassandra TTL architecture

Deep-dive on Cassandra TTL: default vs per-column, expiration, tombstones, gc_grace_seconds, TWCS, tombstone bloat, monitoring.

TTL

Per-cell TTL. Interaction with compaction. Best practices.

Tunable Consistency Worked Examples

Five real workloads and what CL to pick.

Cassandra 5 Vector Search

Native ANN with SAI in the database you already run.

Cassandra vnodes architecture

Deep-dive on Cassandra virtual nodes: how many small tokens per node subdivide the ring, why num_tokens and the rack-aware allocation algorithm contro…

Cassandra vs ScyllaDB in 2026

When the C++ rewrite is worth the migration.

Write Amplification in Cassandra

Write once, hit disk many times. Understand + minimize.

Cassandra Write Path

How Cassandra makes writes durable via CommitLog, buffers in MemTable, and flushes to SSTables on disk.

Cassandra Write and Read Path Architecture in Depth

A 2500-word walkthrough of Cassandra's write and read paths: coordinator, consistency level, memtable, SSTable, bloom, compac…