Re: Overhead cost of Serializable Snapshot Isolation

On Tue, Oct 11, 2011 at 9:21 PM, Greg Sabino Mullane <greg(at)endpoint(dot)com> wrote:

> Simon Riggs:
>> Most apps use mixed mode serializable/repeatable read and therefore
>> can't be changed by simple parameter. Rewriting the application isn't
>> a sensible solution.
>>
>> I think it's clear that SSI should have had and still needs an "off
>> switch" for cases that cause performance problems.
>
> Eh? It has an off switch: repeatable read.

You mean: if we recode the application and retest it, we can get it to
work same way as it used to.

To most people that is the same thing as "it doesn't work with this
release", ask any application vendor.

There is no off switch and there should be.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
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