https://kdpisda.in/tag/clickhouse/Recent content in Clickhouse on Kuldeep PisdaHugoen-usMon, 21 Sep 2026 09:00:00 +0530https://kdpisda.in/walshadow-postgres-wal-level-logical-still-required/Mon, 21 Sep 2026 09:00:00 +0530https://kdpisda.in/walshadow-postgres-wal-level-logical-still-required/<p>On September 10, ClickHouse open-sourced WalShadow, a Postgres-to-ClickHouse replication engine that reads Postgres&rsquo;s physical WAL instead of using logical replication. In ClickHouse&rsquo;s own benchmark, a transaction committed in Postgres became visible in ClickHouse in about 200ms and the pipeline sustained 289,000 rows per second, against roughly 10 seconds and 120,000 rows per second for PeerDB, the logical-replication-based CDC tool ClickHouse acquired and already runs in production as ClickPipes.[1] The pitch is that going around logical replication removes its operational overhead: no replication slot, no output plugin, less load on the source.</p>