Discussion of PostgreSQL's performance issues. Please see Guide to reporting problems and Slow Query Questions for some tips on how to write your performance question.
| Thread | Author | Time |
|---|---|---|
| Indexes on expressions with multiple columns and operators 📎 | Frédéric Yhuel | 13:55 |
| Re: Indexes on expressions with multiple columns and operators | Laurenz Albe | 14:22 |
| Re: Indexes on expressions with multiple columns and operators | Tom Lane | 14:41 |
| Re: Indexes on expressions with multiple columns and operators | Frédéric Yhuel | 14:57 |
| Re: Indexes on expressions with multiple columns and operators | Frédéric Yhuel | 15:33 |
| Thread | Author | Time |
|---|---|---|
| Why isn't PG using an index-only scan? | Jean-Christophe BOGGIO | 06:36 |
| Re: Why isn't PG using an index-only scan? | David Rowley | 07:20 |
| Re: Why isn't PG using an index-only scan? | Jean-Christophe BOGGIO | 07:45 |
| Re: Why isn't PG using an index-only scan? | Andrei Lepikhov | 07:55 |
| Re: Why isn't PG using an index-only scan? | David Rowley | 11:32 |
| Re: Why isn't PG using an index-only scan? | David Rowley | 11:35 |
| Re: Why isn't PG using an index-only scan? | Andrei Lepikhov | 11:55 |
| Re: Indexes on expressions with multiple columns and operators | Jehan-Guillaume de Rorthais | 15:26 |
| Re: Indexes on expressions with multiple columns and operators | Tom Lane | 15:32 |
| Re: Indexes on expressions with multiple columns and operators 📎 | Tom Lane | 16:40 |
| Re: Indexes on expressions with multiple columns and operators | Ranier Vilela | 16:48 |
| Re: Indexes on expressions with multiple columns and operators | Tom Lane | 16:59 |
| Thread | Author | Time |
|---|---|---|
| Re: Why isn't PG using an index-only scan? | David Rowley | 01:05 |
| Re: Indexes on expressions with multiple columns and operators | Frédéric Yhuel | 07:50 |
| Re: Why isn't PG using an index-only scan? | Andrei Lepikhov | 07:50 |
| Re: Indexes on expressions with multiple columns and operators | Jehan-Guillaume de Rorthais | 14:37 |
| Re: Poor row estimates from planner, stat `most_common_elems` sometimes missing for a text[] column | Matt Long | 18:26 |
| Re: Poor row estimates from planner, stat `most_common_elems` sometimes missing for a text[] column | Tom Lane | 19:23 |
| Thread | Author | Time |
|---|---|---|
| Re: Indexes on expressions with multiple columns and operators | Tom Lane | 16:51 |
| Thread | Author | Time |
|---|---|---|
| Re: Indexes on expressions with multiple columns and operators | Frédéric Yhuel | 13:37 |
| Re: Indexes on expressions with multiple columns and operators | Andrei Lepikhov | 13:57 |
| Re: Indexes on expressions with multiple columns and operators | Frédéric Yhuel | 16:09 |
| Re: Indexes on expressions with multiple columns and operators | Andrei Lepikhov | 21:15 |
| Thread | Author | Time |
|---|---|---|
| Re: Indexes on expressions with multiple columns and operators | Frédéric Yhuel | 10:20 |
| Re: Indexes on expressions with multiple columns and operators | Andrei Lepikhov | 10:43 |
| Re: Indexes on expressions with multiple columns and operators | Frédéric Yhuel | 13:31 |
| Very expensive update to update a single row | Dirschel, Steve | 19:40 |
| Re: Very expensive update to update a single row | Sean M | 21:12 |
| Thread | Author | Time |
|---|---|---|
| Re: Indexes on expressions with multiple columns and operators | Frédéric Yhuel | 10:41 |
| Re: Indexes on expressions with multiple columns and operators | Frédéric Yhuel | 10:43 |
| Partition pruning is not happening (even in PG18) | Lauro Ojeda | 19:34 |
| Re: Partition pruning is not happening (even in PG18) | Michał Kłeczek | 20:10 |
| Re: Partition pruning is not happening (even in PG18) | Michał Kłeczek | 20:13 |
| Re: Partition pruning is not happening (even in PG18) | David Rowley | 20:17 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 10:13 |
| Re: Partition pruning is not happening (even in PG18) | Lauro Ojeda | 13:49 |
| Re: Partition pruning is not happening (even in PG18) | Chetan | 20:05 |
| Re: Partition pruning is not happening (even in PG18) | David Rowley | 20:08 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 05:54 |
| Thread | Author | Time |
|---|---|---|
| Question about nested loops.. | Frits Jalvingh | 08:52 |
| Re: Question about nested loops.. | Andrei Lepikhov | 10:00 |
| Re: Poor performance with row wise comparisons | Peter Geoghegan | 21:53 |
| Thread | Author | Time |
|---|---|---|
| Re: Poor performance with row wise comparisons | lokesh | 04:21 |
| Re: Question about nested loops.. | Andrei Lepikhov | 09:28 |
| Thread | Author | Time |
|---|---|---|
| Re: Poor performance with row wise comparisons | David G. Johnston | 23:03 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 04:57 |
| Thread | Author | Time |
|---|---|---|
| Re: Indexes on expressions with multiple columns and operators | Andrei Lepikhov | 13:56 |
| Re: Indexes on expressions with multiple columns and operators | Andrei Lepikhov | 14:00 |
| Re: Indexes on expressions with multiple columns and operators | Tom Lane | 14:55 |
| Thread | Author | Time |
|---|---|---|
| Re: Indexes on expressions with multiple columns and operators | Andrei Lepikhov | 09:29 |
| Thread | Author | Time |
|---|---|---|
| Performance implications of partitioning by UUIDv7 range in PostgreSQL v18 | Jonathan Reis | 03:37 |
| Re: Performance implications of partitioning by UUIDv7 range in PostgreSQL v18 | David Rowley | 19:55 |
| Re: Performance implications of partitioning by UUIDv7 range in PostgreSQL v18 | Olof Salberger | 21:05 |
| Thread | Author | Time |
|---|---|---|
| Re: Performance implications of partitioning by UUIDv7 range in PostgreSQL v18 | Greg Sabino Mullane | 16:51 |
| Re: Performance implications of partitioning by UUIDv7 range in PostgreSQL v18 | Jonathan Reis | 20:11 |
| Re: Performance implications of partitioning by UUIDv7 range in PostgreSQL v18 | Laurenz Albe | 20:38 |
| Re: Performance implications of partitioning by UUIDv7 range in PostgreSQL v18 | David Rowley | 22:54 |
| Thread | Author | Time |
|---|---|---|
| Re: Performance implications of partitioning by UUIDv7 range in PostgreSQL v18 | Jonathan Reis | 02:14 |
| Re: Performance implications of partitioning by UUIDv7 range in PostgreSQL v18 | Laurenz Albe | 05:04 |
| Re: Performance implications of partitioning by UUIDv7 range in PostgreSQL v18 | Greg Sabino Mullane | 12:38 |
| Re: Performance implications of partitioning by UUIDv7 range in PostgreSQL v18 | Jonathan Reis | 15:24 |
| Thread | Author | Time |
|---|---|---|
| GEQO plans much slower than standard join plans 📎 | Carlo Sganzerla | 18:17 |
| Thread | Author | Time |
|---|---|---|
| Re: GEQO plans much slower than standard join plans | Tomas Vondra | 01:24 |
| Re: GEQO plans much slower than standard join plans 📎 | Carlo Sganzerla | 15:43 |
| Thread | Author | Time |
|---|---|---|
| Re: GEQO plans much slower than standard join plans | Tomas Vondra | 02:05 |
| Re: GEQO plans much slower than standard join plans | Carlo Sganzerla | 14:57 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 16:27 |
| Thread | Author | Time |
|---|---|---|
| Re: GEQO plans much slower than standard join plans | David Rowley | 01:19 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 20:40 |
| Thread | Author | Time |
|---|---|---|
| trgm and index-usage when using similarity function | Andreas Joseph Krogh | 08:18 |
| Problem getting query to use index inside a function | Dirschel, Steve | 16:02 |
| Re: Problem getting query to use index inside a function | Tom Lane | 16:18 |
| RE: [EXT] Re: Problem getting query to use index inside a function | Dirschel, Steve | 16:55 |
| Re: [EXT] Re: Problem getting query to use index inside a function | Tom Lane | 19:17 |
| RE: [EXT] Re: Problem getting query to use index inside a function | Dirschel, Steve | 20:18 |
| Thread | Author | Time |
|---|---|---|
| Index Searches higher than expected for skip scan | Michael Christofides | 19:00 |
| Re: Index Searches higher than expected for skip scan 📎 | Peter Geoghegan | 19:54 |
| Re: Index Searches higher than expected for skip scan | Peter Geoghegan | 20:39 |
| Thread | Author | Time |
|---|---|---|
| Re: Index Searches higher than expected for skip scan | Michael Christofides | 11:16 |
| Re: Index Searches higher than expected for skip scan | Peter Geoghegan | 15:00 |
| Thread | Author | Time |
|---|---|---|
| Multicolumn index scan efficiency | Vitalii Tymchyshyn | 02:44 |
| Re: Multicolumn index scan efficiency | Peter Geoghegan | 04:20 |
| Re: Multicolumn index scan efficiency | Vitalii Tymchyshyn | 05:12 |
| Re: proposal: schema variables 📎 | Pavel Stehule | 06:40 |
| Re: Multicolumn index scan efficiency | Peter Geoghegan | 17:00 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 19:59 |
| Re: proposal: schema variables 📎 | Pavel Stehule | 21:19 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables | Pavel Stehule | 04:43 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 06:01 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 04:27 |
| Re: proposal: schema variables | Jim Jones | 13:44 |
| Client-server communication for FETCH | Tim Fors | 18:02 |
| Re: Client-server communication for FETCH | Tom Lane | 18:41 |
| Re: Client-server communication for FETCH | Tim Fors | 19:45 |
| Thread | Author | Time |
|---|---|---|
| Why is my query 3 times faster on my workstation than on my server? | Vincent Veyron | 18:46 |
| Re: Why is my query 3 times faster on my workstation than on my server? | Pavel Stehule | 18:53 |
| Re: Why is my query 3 times faster on my workstation than on my server? | Tom Lane | 19:06 |
| RE: Why is my query 3 times faster on my workstation than on my server? | Clay Jackson (cjackson) | 19:51 |
| Re: Why is my query 3 times faster on my workstation than on my server? | Vincent Veyron | 22:56 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 06:50 |
| Re: Client-server communication for FETCH | Jan Claeys | 09:08 |
| Seeking guidance on extremely slow pg_restore despite strong I/O performance | MentionTheElephant | 10:30 |
| Re: Seeking guidance on extremely slow pg_restore despite strong I/O performance | pg254kl | 20:27 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables | Jim Jones | 11:29 |
| Thread | Author | Time |
|---|---|---|
| Re: Seeking guidance on extremely slow pg_restore despite strong I/O performance | Jeff Janes | 00:53 |
| Re: proposal: schema variables 📎 | Pavel Stehule | 08:15 |
| Re: proposal: schema variables 📎 | Pavel Stehule | 13:57 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 05:51 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 14:46 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 04:42 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 07:52 |
| Thread | Author | Time |
|---|---|---|
| Surprising optimizer behavior with a subquery, a GROUP BY, and a range filter | wotq | 20:26 |
| Re: Surprising optimizer behavior with a subquery, a GROUP BY, and a range filter | Tom Lane | 20:46 |
| Thread | Author | Time |
|---|---|---|
| Unexpected planner choice in simple JOIN | Mark Kirkwood | 01:35 |
| Re: Unexpected planner choice in simple JOIN | Mark Kirkwood | 03:34 |
| Re: Unexpected planner choice in simple JOIN | David Rowley | 03:56 |
| Re: Unexpected planner choice in simple JOIN | Mark Kirkwood | 04:03 |
| Re: Unexpected planner choice in simple JOIN | David Rowley | 04:14 |
| Re: Unexpected planner choice in simple JOIN | Mark Kirkwood | 04:24 |
| Re: Unexpected planner choice in simple JOIN | Tom Lane | 04:34 |
| Re: Unexpected planner choice in simple JOIN | Mark Kirkwood | 04:44 |
| Re: Unexpected planner choice in simple JOIN | Tom Lane | 04:51 |
| Re: Unexpected planner choice in simple JOIN | Mark Kirkwood | 04:55 |
| Thread | Author | Time |
|---|---|---|
| Another unexpected planner choice in simple JOIN | Mark Kirkwood | 00:12 |
| Re: Another unexpected planner choice in simple JOIN | Mark Kirkwood | 01:15 |
| Re: proposal: schema variables 📎 | Pavel Stehule | 08:45 |
| Troubleshooting a brief spike in active sessions | Dirschel, Steve-CW | 21:41 |
| Re: Troubleshooting a brief spike in active sessions | Joshua Banton | 21:58 |
| Re: Troubleshooting a brief spike in active sessions | Nikolay Samokhvalov | 22:27 |
| Re: Troubleshooting a brief spike in active sessions | Nikolay Samokhvalov | 22:29 |
| Thread | Author | Time |
|---|---|---|
| small database huge planning time 📎 | Alexander Kulikov | 09:16 |
| Re: small database huge planning time | Andrei Lepikhov | 09:29 |
| Re: small database huge planning time | Greg Sabino Mullane | 14:44 |
| Re: small database huge planning time | Huanbing Lu | 16:07 |
| Thread | Author | Time |
|---|---|---|
| Slow queries on simple index | Lillian Berry | 13:58 |
| Re: Slow queries on simple index | Pavel Stehule | 14:59 |
| Re: Slow queries on simple index | Ken Marshall | 15:28 |
| Re: Slow queries on simple index | Tom Lane | 16:57 |
| Re: Slow queries on simple index | Lillian Berry | 19:33 |
| Re: Slow queries on simple index | Andrei Lepikhov | 20:21 |
| Re: Slow queries on simple index | Lillian Berry | 20:52 |
| Re: Slow queries on simple index | Tom Lane | 21:10 |
| [Solved] Slow queries on simple index | Lillian Berry | 22:06 |
| Thread | Author | Time |
|---|---|---|
| Re: Slow queries on simple index | Andrei Lepikhov | 09:24 |
| Thread | Author | Time |
|---|---|---|
| Re: small database huge planning time 📎 | Andrei Lepikhov | 22:12 |
| Thread | Author | Time |
|---|---|---|
| performance impact on read replicas during heavy vacuums on primary | Dirk Krautschick | 01:02 |
| Thread | Author | Time |
|---|---|---|
| Re: performance impact on read replicas during heavy vacuums on primary | Greg Sabino Mullane | 16:29 |
| Thread | Author | Time |
|---|---|---|
| Postgres IO sweet spot | Riaan Stander | 23:13 |
| Thread | Author | Time |
|---|---|---|
| LATERAL subquery predicate pushdown: filter applied after JSON construction instead of inside join (PG 18) 📎 | Nyasha Chigwamba | 16:12 |
| Re: LATERAL subquery predicate pushdown: filter applied after JSON construction instead of inside join (PG 18) | Tom Lane | 17:37 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 19:25 |
| Thread | Author | Time |
|---|---|---|
| A serious change in performance between PG 15 and PG 16, 17, 18. | Clive Boughton | 03:49 |
| Re: A serious change in performance between PG 15 and PG 16, 17, 18. | Tom Lane | 04:03 |
| Re: A serious change in performance between PG 15 and PG 16, 17, 18. | David Rowley | 04:04 |
| Re: A serious change in performance between PG 15 and PG 16, 17, 18. | David G. Johnston | 04:04 |
| Re: A serious change in performance between PG 15 and PG 16, 17, 18. | Andrei Lepikhov | 09:05 |
| Re: Postgres IO sweet spot | Riaan Stander | 14:57 |
| Re: Postgres IO sweet spot | Greg Sabino Mullane | 15:34 |
| Re: A serious change in performance between PG 15 and PG 16, 17, 18. | Joe Conway | 15:42 |
| Thread | Author | Time |
|---|---|---|
| Re: Postgres IO sweet spot | Riaan Stander | 23:42 |
| Thread | Author | Time |
|---|---|---|
| Re: A serious change in performance between PG 15 and PG 16, 17, 18. | David Rowley | 00:01 |
| Re: A serious change in performance between PG 15 and PG 16, 17, 18. | Clive Boughton | 01:05 |
| Thread | Author | Time |
|---|---|---|
| unstable query plan on pg 16,17,18 | Attila Soki | 09:37 |
| Re: unstable query plan on pg 16,17,18 | Laurenz Albe | 09:41 |
| Re: LATERAL subquery predicate pushdown: filter applied after JSON construction instead of inside join (PG 18) | Nyasha Chigwamba | 10:52 |
| MERGE INTO... WHEN NOT MATCHED BY SOURCE index usage | Lea Führer | 14:18 |
| Re: unstable query plan on pg 16,17,18 | Attila Soki | 15:10 |
| Re: unstable query plan on pg 16,17,18 | Andrei Lepikhov | 15:54 |
| Re: unstable query plan on pg 16,17,18 | Attila Soki | 17:03 |
| Re: unstable query plan on pg 16,17,18 | Laurenz Albe | 19:59 |
| Re: unstable query plan on pg 16,17,18 | Andrei Lepikhov | 20:25 |
| Re: unstable query plan on pg 16,17,18 | Attila Soki | 20:42 |
| Re: unstable query plan on pg 16,17,18 | Laurenz Albe | 20:54 |
| Re: unstable query plan on pg 16,17,18 | Attila Soki | 21:19 |
| Re: unstable query plan on pg 16,17,18 | Laurenz Albe | 21:44 |
| Thread | Author | Time |
|---|---|---|
| Re: unstable query plan on pg 16,17,18 | Andrei Lepikhov | 09:11 |
| Re: unstable query plan on pg 16,17,18 | Attila Soki | 09:16 |
| Re: unstable query plan on pg 16,17,18 | Andrei Lepikhov | 11:09 |
| Re: unstable query plan on pg 16,17,18 | Attila Soki | 11:37 |
| Re: unstable query plan on pg 16,17,18 | Attila Soki | 15:50 |
| Re: unstable query plan on pg 16,17,18 | Andrei Lepikhov | 15:57 |
| Re: unstable query plan on pg 16,17,18 | Attila Soki | 16:48 |
| Re: unstable query plan on pg 16,17,18 📎 | Andrei Lepikhov | 19:20 |
| Thread | Author | Time |
|---|---|---|
| Re: MERGE INTO... WHEN NOT MATCHED BY SOURCE index usage | Feike Steenbergen | 16:35 |
| Thread | Author | Time |
|---|---|---|
| Re: unstable query plan on pg 16,17,18 | Attila Soki | 16:15 |
| Re: unstable query plan on pg 16,17,18 | Attila Soki | 16:22 |
| Re: unstable query plan on pg 16,17,18 | Laurenz Albe | 20:53 |
| Thread | Author | Time |
|---|---|---|
| Re: unstable query plan on pg 16,17,18 | Andrei Lepikhov | 08:15 |
| Re: unstable query plan on pg 16,17,18 | Attila Soki | 15:00 |
| Re: unstable query plan on pg 16,17,18 | Andrei Lepikhov | 15:35 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables | Haritabh Gupta | 10:02 |
| Re: proposal: schema variables | Pavel Stehule | 19:15 |
| Thread | Author | Time |
|---|---|---|
| Re: proposal: schema variables 📎 | Pavel Stehule | 12:54 |
| Planner join order regression from PG 15 to PG 16+: 70ms -> 1440ms (self-contained reproducer included) 📎 | Mauro Gatti | 16:25 |
| Re: Planner join order regression from PG 15 to PG 16+: 70ms -> 1440ms (self-contained reproducer included) 📎 | Andrei Lepikhov | 19:09 |