PostgreSQL's MVCC is bad. So is everyone else's
Bloated tables that double in size, 32-bit transaction counter limit, the never ending struggle with VACCUM, dead tuples nightmares. It comes with credentials, too: Uber measured the write amplification in 2016 and left for MySQL over it; Andy Pavlo's database group called MVCC the part of PostgreSQL they hate the most. While none of this is exaggerated, it comes down to a real design choice.
- ▪Bloated tables that double in size, 32-bit transaction counter limit, the never ending struggle with VACCUM, dead tuples nightmares.
- ▪It comes with credentials, too: Uber measured the write amplification in 2016 and left for MySQL over it; Andy Pavlo's database group called MVCC the part of PostgreSQL they hate the most.
- ▪While none of this is exaggerated, it comes down to a real design choice.
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| Original publisher | boringSQL | Supercharge your SQL & PostgreSQL powers |
| Canonical URL | https://boringsql.com/posts/mvcc-bad-bad/ |
| Publication time | Wed, 29 Jul 2026 14:58:17 +0000 |
| Retrieval time | 2026-07-29T15:45:59.847Z |
| Last seen | 2026-07-29T15:45:59.847Z |
| Headline source | Publisher (no WeSearch rewrite) |
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| Summary | WeSearch · cerebras-chat (WeSearch summarizer) |
| Summary source text | contentText |
| Citation coverage | Summary is a WeSearch-generated derivative; primary citation is the original publisher URL. |
| Cluster | ZAPUZy_eVfYh · 1 stories |
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| Ranking reason | Story pages are not engagement-ranked. Hub feeds use recency, with optional source-diversified chronological ordering (cap consecutive stories per source). No personalized ranking. |
| Publisher visit | Yes — open original |
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| Indexing | May the item be indexed (stored, ranked, made findable)? | Allowed |
| Snippet | May a short excerpt of the publisher's text be shown? | Allowed |
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| Retrieval / RAG | May the content be exposed for third-party retrieval-augmented generation? | Not asserted |
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| Commercial reuse | May the content be reused commercially? | Not permitted |
Basis: Derived from the published RSS/Atom feed. Contact: [email protected]. Reviewed: 2026-07-24.
Opening excerpt (first ~120 words) tap to expand
Table of Contents The charges against PostgreSQL Charge 1: write amplification Charge 2: your table is an accident scene Charge 3: one idle transaction poisons the well Charge 4: the 32-bit debt The undo camp: Oracle and InnoDB SQL Server: versioning as an optional extra MongoDB: versions in the cache The LSM generation: garbage collection as a lifestyle Outside the RDBMS entirely: etcd Fixing PostgreSQL itself The scorecard The first thing you will probably learn about Postgres, if you follow people who don't like Postgres, is that MVCC is bad. The 40-year-old design mistake. It's signatures are everywhere. Bloated tables that double in size, 32-bit transaction counter limit, the never ending struggle with VACCUM, dead tuples nightmares.
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Excerpt limited to ~120 words for fair-use compliance. The full article is at boringSQL | Supercharge your SQL & PostgreSQL powers.
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