> "Bulk loads ...",
As I see -
There is an interesting bulkload benchmark:
"How
Bulkload performance is affected by table partitioning in PostgreSQL"
by Beena Emerson (Enterprisedb, December 4, 2019 )
SUMMARY:
This article covers how benchmark tests can be used to demonstrate the
effect of table partitioning on performance. Tests using range- and
hash-partitioned tables are compared and the reasons for their different
results are explained:
1. Range partitions
2. Hash partitions
3. Combination graphs
4. Explaining the behavior
5.
Conclusion
"For the
hash-partitioned table, the first value is inserted in the first
partition, the second number in the second partition and so on till all
the partitions are reached before it loops back to the first partition
again until all the data is exhausted. Thus it exhibits the worst-case
scenario where the partition is repeatedly switched for every value
inserted. As a result, the number of times the partition is switched in a
range-partitioned table is equal to the number of partitions, while in a
hash-partitioned table, the number of times the partition has switched
is equal to the amount of data being inserted. This causes the massive
difference in timing for the two partition types."
Regards,
Imre
