On Sat, Apr 23, 2011 at 2:57 PM, Gianni Ciolli
<gianni.ciolli@2ndquadrant.it> wrote:
> * "avg_usec" denotes the average time in microseconds required by each
> NOTIFY statement.
>
> h2. Test 1 - PostgreSQL HEAD
>
> n | m | iter | avg_usec
> -------+-------+------+----------
> 10 | 1 | 10 | 43.730
> 100 | 1 | 10 | 37.630
> 1000 | 1 | 10 | 42.990
> 10000 | 1 | 10 | 36.225
> 10 | 10 | 10 | 43.960
> 100 | 100 | 10 | 46.537
> 1000 | 1000 | 10 | 126.115
> 10000 | 10000 | 10 | 906.501
I read that wrong first time around. So the wasted time from duplicate checks is
n | m | iter | msec-------+-------+------+---------- 10 | 10 | 10 | 0 100 | 100 | 10 | 0.3 1000
| 1000 | 10 | 80 10000 | 10000 | 10 | 8600
So the cost of the duplicate checks only kicks in at about 200 notifies.
--
Simon Riggs http://www.2ndQuadrant.com/
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