Re: Overhead cost of Serializable Snapshot Isolation

On Mon, Oct 10, 2011 at 8:30 PM, Heikki Linnakangas
<heikki.linnakangas@enterprisedb.com> wrote:
> On 10.10.2011 21:25, Greg Sabino Mullane wrote:
>>
>> I agree it is better versus SELECT FOR, but what about repeatable read
>> versus
>> the new serializable? How much overhead is there in the 'monitoring of
>> read/write dependencies'? This is my only concern at the moment. Are we
>> talking insignificant overhead? Minor? Is it measurable? Hard to say
>> without
>> knowing the number of txns, number of locks, etc.?
>
> I'm sure it does depend heavily on all of those things, but IIRC Kevin ran
> some tests earlier in the spring and saw a 5% slowdown. That feels like
> reasonable initial guess to me. If you can run some tests and measure the
> overhead in your application, it would be nice to hear about it.

How do we turn it on/off to allow the overhead to be measured?

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