Re: Parallel COPY FROM execution

2017-06-30 15:45 GMT+02:00 Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>:

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> 2017-06-30 15:42 GMT+02:00 Alex K <kondratov(dot)aleksey(at)gmail(dot)com>:
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>> On Fri, Jun 30, 2017 at 3:35 PM, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>
>> wrote:
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>> > 2017-06-30 14:23 GMT+02:00 Alex K <kondratov(dot)aleksey(at)gmail(dot)com>:
>> >>
>> >> Thus, it results in a ~60% performance boost per each x2
>> multiplication of
>> >> parallel processes, which is consistent with the initial estimation.
>> >>
>> >
>> > the important use case is big table with lot of indexes. Did you test
>> > similar case?
>>
>> Not yet, I will try it, thank you for a suggestion. But how much is it
>> 'big table' and 'lot of indexes' in numbers approximately?
>>
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> the size is about 1/3 RAM size, 60 columns, 30 indexes
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maybe some variants can be interesting .. 1/30 RAM, 1/20 RAM, 1/10 RAM, 1/3
RAM

and a) when bottleneck is IO, b) when bottleneck is CPU

Pavel

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> Regards
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> Pavel
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>>
>> Also, index updates and constraint checks performance are what I cannot
>> control during COPY execution, so probably I have not to care too much
>> about that. But of course, it is interesting, how does COPY perform in
>> that case.
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>>
>> Alexey
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