Re: Why HDD performance is better than SSD in this case

From: Mark Kirkwood
Subject: Re: Why HDD performance is better than SSD in this case
Date: ,
Msg-id: c8c36fe8-e1a8-694a-70db-72f32bcda781@catalyst.net.nz
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In response to: Re: Why HDD performance is better than SSD in this case  (Neto pr)
List: pgsql-performance

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Why HDD performance is better than SSD in this case  (Neto pr, )
 Re: Why HDD performance is better than SSD in this case  (Benjamin Scherrey, )
  Re: Why HDD performance is better than SSD in this case  (winston cheung, )
 Re: Why HDD performance is better than SSD in this case  (Mark Kirkwood, )
 Re: Why HDD performance is better than SSD in this case  (Robert Zenz, )
 Re: Why HDD performance is better than SSD in this case  (Fabio Pardi, )
  Re: Why HDD performance is better than SSD in this case  (Neto pr, )
   Re: Why HDD performance is better than SSD in this case  (Neto pr, )
    Re: Why HDD performance is better than SSD in this case  (Nicolas Charles, )
     Re: Why HDD performance is better than SSD in this case  (Robert Zenz, )
      Re: Why HDD performance is better than SSD in this case  (Nicolas Charles, )
     Re: Why HDD performance is better than SSD in this case  (Neto pr, )
      Re: Why HDD performance is better than SSD in this case  (Nicolas Charles, )
     Re: Why HDD performance is better than SSD in this case  (Mark Kirkwood, )
    Re: Why HDD performance is better than SSD in this case  (Fabio Pardi, )
     Re: Why HDD performance is better than SSD in this case  (Neto pr, )
      Re: Why HDD performance is better than SSD in this case  (Fabio Pardi, )
       Re: Why HDD performance is better than SSD in this case  (Neto pr, )
        Re: Why HDD performance is better than SSD in this case  (Fabio Pardi, )
   Re: Why HDD performance is better than SSD in this case  (Mark Kirkwood, )
    Re: Why HDD performance is better than SSD in this case  (Neto pr, )
     Re: Why HDD performance is better than SSD in this case  (Neto pr, )
      Re: Why HDD performance is better than SSD in this case  (Nicolas Charles, )
      Re: Why HDD performance is better than SSD in this case  (Imre Samu, )
     Re: Why HDD performance is better than SSD in this case  (Mark Kirkwood, )
     Re: Why HDD performance is better than SSD in this case  (Mark Kirkwood, )
      Re: Why HDD performance is better than SSD in this case  (Mark Kirkwood, )
       Re: Why HDD performance is better than SSD in this case  (Neto pr, )
        Re: Why HDD performance is better than SSD in this case  (Mark Kirkwood, )
       Re: Why HDD performance is better than SSD in this case  (Mark Kirkwood, )
 Re: Why HDD performance is better than SSD in this case  (Jeff Janes, )
 Re: Why HDD performance is better than SSD in this case  (George Neuner, )

Hi Neto,

In a great piece of timing my new experimental SSD arrived (WD Black 500 
G 3D NAND MVME) [1]. Doing some runs of query 9:

- default config: 7 minutes

- work_mem=1G, max_parallel_workers_per_gather=4: 3-4 minutes


Increasing either of these much more got me OOM errors (16 G of ram). 
Anyway, enjoy your benchmarking!

Cheers
Mark

[1] Yeah - I know this is a 'do not use me in production' type of SSD. 
It is however fine for prototyping and DSS scenario run type use.

On 20/07/18 12:52, Neto pr wrote:
>
> Mark,
> This query 9 is very hard, see my results for other queries (attached
> - test with secondary index and without secondary index - only primary
> keys), the SSD always wins in performance.
> Only for this query that he was the loser, so I put this topic in the list.
>
> Today I will not be able to check your test information in more
> detail, but I will return with more information soon.
>
> Best Regards
> Neto
>
>
>
>
>




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