Articles by ChistaDATA Inc.

About ChistaDATA Inc.

We are an full-stack ClickHouse infrastructure operations Consulting, Support and Managed Services provider with core expertise in performance, scalability and data SRE. Based out of California, Our consulting and support engineering team operates out of San Francisco, Vancouver, London, Germany, Russia, Ukraine, Australia, Singapore and India to deliver 24*7 enterprise-class consultative support and managed services. We operate very closely with some of the largest and planet-scale internet properties like PayPal, Garmin, Honda cars IoT project, Viacom, National Geographic, Nike, Morgan Stanley, American Express Travel, VISA, Netflix, PRADA, Blue Dart, Carlsberg, Sony, Unilever etc

ClickHouse Explain

ClickHouse EXPLAIN PIPELINE: A Proven 7-Step Guide to Decoding Query Execution Bottlenecks

ChistaDATA Inc.

Read ClickHouse EXPLAIN PIPELINE like a principal engineer: processor names, x1 choke points, and measured confirmation via system.processors_profile_log.

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Memory Limit Exceeded in ClickHouse: Root Causes and Permanent Fixes

ChistaDATA Inc.

Fix ClickHouse memory limit exceeded (code 241) for good: error taxonomy, external aggregation, join strategy, and layered per-query limits.

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Troubleshooting ClickHouse high CPU usage with the sampling profiler, system.trace_log stacks and flamegraphs

Troubleshooting High CPU Usage in ClickHouse: From system.trace_log to Flamegraphs

ChistaDATA Inc.

Diagnose ClickHouse high CPU usage with the sampling profiler, system.trace_log stacks, and flamegraphs, plus the five hotspots we see most often.

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ClickHouse latency analysis featured image: query duration distribution for one query shape with p50, p95 and p99 markers highlighting the latency tail

ClickHouse p95/p99 Latency Regression Analysis: A Data SRE Playbook

ChistaDATA Inc.

A Data SRE playbook for ClickHouse latency analysis: baseline p95/p99 per query shape, detect regressions in query_log, and fix root causes.

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ClickHouse

Using EXPLAIN PIPELINE to Decode ClickHouse Query Execution Bottlenecks

ChistaDATA Inc.

Learn to read ClickHouse EXPLAIN PIPELINE processor graphs, spot single-threaded stages and pipeline stalls, and fix production bottlenecks.

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ClickHouse slow query troubleshooting: diagnosing query latency with system.query_log, a ChistaDATA production methodology

Diagnosing Slow ClickHouse Queries with system.query_log: A Production Methodology

ChistaDATA Inc.

Master ClickHouse slow query troubleshooting with a production-proven system.query_log methodology to find, classify, and fix query latency fast.

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ClickHouse Ingestion Performance: Batch Sizing, Async Inserts, and Kafka Pipelines

ChistaDATA Inc.

ClickHouse ingestion performance is decided long before the query planner ever touches your data. It is decided by how many parts your writers create per second, how much background merge work those parts generate, and […]

ClickHouse Merge Performance: Diagnosing Too Many Parts, Slow Merges, and Stuck Mutations

ChistaDATA Inc.

ClickHouse merge performance is the hinge on which every high-ingest MergeTree deployment turns. When background merges keep pace with inserts, part counts stay flat and SELECT latency stays predictable. When they fall behind, the failure […]

Scaling ClickHouse Horizontally: Sharding, Distributed Tables, and Parallel Replicas

ChistaDATA Inc.

Horizontal scale is where most ClickHouse fleets accumulate their deepest operational debt. ClickHouse sharding gets introduced months before the workload justifies it, and once a sharding key is baked into a production Distributed table, unwinding […]

ClickHouse MergeTree Optimization: Sort Keys, Partitioning, Skip Indexes, and Projections

ChistaDATA Inc.

ClickHouse MergeTree optimization is the difference between a table that answers analytical queries in milliseconds and one that scans hundreds of gigabytes for every request. This guide is written for senior engineers who already understand […]