On 04.01.2013 22:05, Josh Berkus wrote:
>> Next question is what people think about back-patching into 9.2 so as
>> to eliminate the performance regression vs 9.1. I believe this would
>> be safe (although some care would have to be taken to put the added
>> boolean fields into places where they'd not result in an ABI break).
>> However it may not be worth the risk. The 40% slowdown seen with
>> Pavel's example seems to me to be an extreme corner case --- Dong's
>> result of 8% slowdown is probably more realistic for normal uses
>> of SPI_execute. Might be better to just live with it in 9.2.
> 8% is a pretty serious regression, for those of us with applications
> which do a lot of dynamic SQL. As a reminder, many people do dynamic
> SQL even in repetitive, performance-sensitive functions in order to
> avoid plan caching. Also partition-handlers often use dynamic SQL, and
> a 10% drop in loading rows/second would be a big deal.
+1 for backpatching.
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