Andrew Dunstan wrote:
>
>
> Heikki Linnakangas wrote:
>> Here's a patch to speed up CopyReadAttributesCSV. On the test case
>> I've been playing with, loading the TPC-H partsupp table, about 20%
>> CopyReadAttributesCSV (inlined into DoCopy, DoCopy itself is
>> insignificant):
>>
>>
> [snip]
>>
>> The trick is to split the loop in CopyReadAttributesCSV into two
>> parts, inside quotes, and outside quotes, saving some instructions in
>> both parts.
>>
>> Your mileage may vary, but I'm quite happy with this. I haven't tested
>> it much yet, but I wouldn't expect it to be a loss in any interesting
>> scenario. The code also doesn't look much worse after the patch,
>> perhaps even better.
>>
>>
>
> This looks sane enough, and worked for me in testing, so I'm going to
> apply it shortly. I'll probably add a comment or two about how the loops
> interact.
Thanks.
FWIW, I did some more performance testing, with input consisting of a
lot of quotes, and it seems the performance gain holds even then. I was
not able to find an input where the new version performs worse.
--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com
