Re: COPY performance on Windows

Ryohei Takahashi (Fujitsu) писал(а) 2024-12-19 16:13:
> Hi
> 
> 
> Thank you for your advice and testing.
> 
>> I think, it could be checked, if table has text fields instead of
>> numeric - we could exclude numeric conversion
>> and have the same input-output operations (really more IO-operation, 
>> but
>> we need to compare)
> 
> I changed the column from int to text.
> The performance becomes worse in each version,
> but the rate of the difference of duration did not change.
> 
> 
>> By the way, do you use prebuild Postgres versions for this test or
>> build it by yourself with the same options? I am going to use built
>> myself.
> 
> In the mail in 2024-12-16 12:09:03, I used the modules which I build by 
> myself.
> In the other mail, I used the modules which community provides at 
> following.
> https://www.postgresql.org/download/windows/
> 
> 
>> Could you confirm, that you receive you results on all execution 
>> orders
>> (17.0 first and 17.0 last)?
> 
> In my environment, the results do not depend on order.
> (The performance of the order 16.4, 16.6, 17.0 is same as that of the 
> order 17.0, 16.6, 16.4)
> 
> 
> Regards,
> Ryohei Takahashi

Hi!

  I tested with text (CREATE UNLOGGED TABLE test (c TEXT STORAGE PLAIN) 
WITH (autovacuum_enabled = off)).
Time is ~10% higher, but I also do not see strict dependence on version.

I think, antivirus can influence the performace, I did not switched it 
off.

How can I help you in testing? Probably better to test and compare 
result only with one quantity of clients.
For 1 client the read time of the input file has the big effect, for 
many clients their concurrency overhead has
big effect. Maybe make the series of the runs with 2 or 4 clients only 
and compare?

-- 
Best regards,

Vladlen Popolitov.