| From: | Nathan Bossart <nathandbossart(at)gmail(dot)com> | 
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> | 
| Cc: | Andrew Dunstan <andrew(at)dunslane(dot)net>, Joe Conway <mail(at)joeconway(dot)com>, Davin Shearer <davin(at)apache(dot)org>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org> | 
| Subject: | Re: Emitting JSON to file using COPY TO | 
| Date: | 2023-12-06 16:33:49 | 
| Message-ID: | 20231206163349.GA2873889@nathanxps13 | 
| Views: | Whole Thread | Raw Message | Download mbox | Resend email | 
| Thread: | |
| Lists: | pgsql-general pgsql-hackers | 
On Wed, Dec 06, 2023 at 11:28:59AM -0500, Tom Lane wrote:
> It might be acceptable to plan on improving the performance later,
> depending on just how bad it is now.
On 10M rows with 11 integers each, I'm seeing the following:
	(format text)
	Time: 10056.311 ms (00:10.056)
	Time: 8789.331 ms (00:08.789)
	Time: 8755.070 ms (00:08.755)
	(format csv)
	Time: 12295.480 ms (00:12.295)
	Time: 12311.059 ms (00:12.311)
	Time: 12305.469 ms (00:12.305)
	(format json)
	Time: 24568.621 ms (00:24.569)
	Time: 23756.234 ms (00:23.756)
	Time: 24265.730 ms (00:24.266)
'perf top' tends to look a bit like this:
  13.31%  postgres                      [.] appendStringInfoString
   7.57%  postgres                      [.] datum_to_json_internal
   6.82%  postgres                      [.] SearchCatCache1
   5.35%  [kernel]                      [k] intel_gpio_irq
   3.57%  postgres                      [.] composite_to_json
   3.31%  postgres                      [.] IsValidJsonNumber
-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Nathan Bossart | 2023-12-06 16:44:39 | Re: Emitting JSON to file using COPY TO | 
| Previous Message | Tom Lane | 2023-12-06 16:28:59 | Re: Emitting JSON to file using COPY TO | 
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Nathan Bossart | 2023-12-06 16:37:10 | Re: Clean up some signal usage mainly related to Windows | 
| Previous Message | Tom Lane | 2023-12-06 16:28:59 | Re: Emitting JSON to file using COPY TO |