Re: Jsonb extraction very slow

Please CC the list.

On 8/11/16 2:19 AM, hari.prasath wrote:
>>Actually I've done some testing with this and there is a *significant*
>>overhead in getting multiple keys from a large document. There's a
>>significant extra cost for the first key, but there's also a non-trivial
>>cost for every key after that.
>
> Why is it take some extra cost for the first key and less for keys after
> that.?
> Is there any specific reason for this.? if so please explain..

I never dug into why. As Tom posited, decompression might explain the
time to get a single key out. Getting 10 keys instead of just 1 wasn't
10x more expensive, but it was significantly more expensive than just
getting a single key.
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