openaienmodel: gpt-5-mini-2025-08-07
R2 Data Catalog compaction now optimizes manifest files
Key Points
- Automatic manifest optimization during compaction
- Rewrites and clusters manifests by partition to cut metadata I/O
- No config changes — runs for compaction-enabled tables
Summary
R2 Data Catalog (the managed Apache Iceberg catalog built into R2) now automatically optimizes manifest files as part of compaction. Manifest files record the data files that make up an Iceberg table; when many small or fragmented manifests accumulate, query engines must read more metadata during planning and queries slow down. During compaction, R2 now rewrites and clusters manifest files by partition as a best-effort pre-step, consolidating fragmented manifests and reducing metadata I/O. Tables that are already well-clustered are skipped. This behavior runs automatically for tables with compaction enabled and requires no configuration changes.
Key Points
- Compaction now rewrites and clusters manifest files by partition to consolidate fragmented manifests.
- Reduces number of manifests a query engine must open and lowers metadata I/O, speeding up query planning.
- Operation is best-effort and skipped for tables that are already well-clustered.
- Runs automatically for tables with compaction enabled; no config changes required.
- Applies to Apache Iceberg tables managed in R2 Data Catalog; non-disruptive metadata optimization.