Re: Parallel copy

On Thu, Feb 20, 2020 at 04:11:39PM +0530, Amit Kapila wrote:
>On Thu, Feb 20, 2020 at 5:12 AM David Fetter <david@fetter.org> wrote:
>>
>> On Fri, Feb 14, 2020 at 01:41:54PM +0530, Amit Kapila wrote:
>> > This work is to parallelize the copy command and in particular "Copy
>> > <table_name> from 'filename' Where <condition>;" command.
>>
>> Apropos of the initial parsing issue generally, there's an interesting
>> approach taken here: https://github.com/robertdavidgraham/wc2
>>
>
>Thanks for sharing.  I might be missing something, but I can't figure
>out how this can help here.  Does this in some way help to allow
>multiple workers to read and tokenize the chunks?
>

I think the wc2 is showing that maybe instead of parallelizing the
parsing, we might instead try using a different tokenizer/parser and
make the implementation more efficient instead of just throwing more
CPUs on it.

I don't know if our code is similar to what wc does, maytbe parsing
csv is more complicated than what wc does.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
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