HASH

Artem Tomyuk <admin@xxxxxxxxxxxxxx> · Thu, 5 Nov 2015 11:11:10 +0200

Hi all.
Is the speed of hash operations stands on the performance of CPU?
Below you can see part from output of explain analyze command

Intel(R) Xeon(R) CPU           E7520  @ 1.87GHz
"              ->  Hash  (cost=337389.43..337389.43 rows=3224443 width=34) (actual time=15046.382..15046.382 rows=3225191 loops=1)"
"                    Buckets: 524288  Batches: 1  Memory Usage: 207874kB"

Intel(R) Xeon(R) CPU E5-2670 v2 @ 2.50GHz

"              ->  Hash  (cost=340758.94..340758.94 rows=3191894 width=34) (actual time=2692.878..2692.878 rows=3192103 loops=1)"
"                    Buckets: 524288  Batches: 1  Memory Usage: 205742kB"

Intel(R) Xeon(R) CPU E5-2650 0 @ 2.00GHz
"              ->  Hash  (cost=337389.43..337389.43 rows=3224443 width=34) (actual time=8559.849..8559.849 rows=3225293 loops=1)"
"                    Buckets: 524288  Batches: 1  Memory Usage: 207881kB"

Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz
"              ->  Hash  (cost=356613.23..356613.23 rows=3224623 width=40) (actual time=3635.931..3635.931 rows=3224623 loops=1)"
"                    Buckets: 524288  Batches: 1  Memory Usage: 207838kB"

Thanks.