explain.depesz.com

PostgreSQL's explain analyze made readable

Result: U5pf

Settings
# exclusive inclusive rows x rows loops node
1. 0.338 762.903 ↑ 1.0 100 1

Limit (cost=49,458.02..49,469.69 rows=100 width=22) (actual time=731.986..762.903 rows=100 loops=1)

2. 34.853 762.565 ↑ 1,201.3 500 1

Gather Merge (cost=49,411.35..119,493.48 rows=600,662 width=22) (actual time=731.777..762.565 rows=500 loops=1)

  • Workers Planned: 2
  • Workers Launched: 2
3. 59.936 727.712 ↑ 792.4 379 3 / 3

Sort (cost=48,411.33..49,162.15 rows=300,331 width=22) (actual time=727.672..727.712 rows=379 loops=3)

  • Sort Key: herald_activity."timestamp" DESC, herald_notification.id DESC
  • Sort Method: top-N heapsort Memory: 103kB
  • Worker 0: Sort Method: top-N heapsort Memory: 103kB
  • Worker 1: Sort Method: top-N heapsort Memory: 103kB
4. 385.172 667.776 ↑ 1.2 240,265 3 / 3

Parallel Hash Join (cost=20,907.47..33,446.16 rows=300,331 width=22) (actual time=393.814..667.776 rows=240,265 loops=3)

  • Hash Cond: (herald_notification.activity_id = herald_activity.id)
5. 74.582 74.582 ↑ 1.2 240,265 3 / 3

Parallel Seq Scan on herald_notification (cost=0.00..6,900.31 rows=300,331 width=14) (actual time=0.026..74.582 rows=240,265 loops=3)

6. 117.277 208.022 ↑ 1.3 313,830 3 / 3

Parallel Hash (cost=14,087.88..14,087.88 rows=392,288 width=12) (actual time=208.022..208.022 rows=313,830 loops=3)

  • Buckets: 131072 Batches: 16 Memory Usage: 3840kB
7. 90.745 90.745 ↑ 1.3 313,830 3 / 3

Parallel Seq Scan on herald_activity (cost=0.00..14,087.88 rows=392,288 width=12) (actual time=0.042..90.745 rows=313,830 loops=3)

Planning time : 1.529 ms
Execution time : 763.068 ms