Date: Fri, 10 Apr 2020 16:04:20 -0400
From: Bruce Momjian <bruce@momjian.us>
To: Lu Dillon <ludi_1981@hotmail.com>
Cc: Iuri Sampaio <iuri.sampaio@gmail.com>, Ed Behn <ed.behn@collins.com>,
	MichaelDBA <MichaelDBA@sqlexec.com>,
	Steve Midgley <science@misuse.org>,
	Erik Brandsberg <erik@heimdalldata.com>,
	"pgsql-sql@lists.postgresql.org" <pgsql-sql@lists.postgresql.org>
Subject: Re: =?utf-8?B?5Zue5aSN?= =?utf-8?Q?=3A?= [External] Re: Separate
 volumes
Message-ID: <20200410200420.GA24987@momjian.us>
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On Tue, Apr  7, 2020 at 04:31:51PM +0000, Lu Dillon wrote:
> Hi All,
> 
> This is a very intersting question. I believe this is not just a best practice
> to PG. We can apply to all RDBMS. In my opinion, I agree with the others: with
> SSD, you don’t separate tables and indexs to different disks. I think the IOPS
> is enough. If you still have a problem of IOPS, you can try NVME device or U2
> device.

If you are mixing magnetic and SSDs for the same database, having
indexes on SSDs can really help, compared to table files on SSDs, where
the benefit is more limited.  Also, having current data on SSDs and
archive data on magnetic is also useful, and you usually use
time-based partitioning for such cases.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EnterpriseDB                             https://enterprisedb.com

+ As you are, so once was I.  As I am, so you will be. +
+                      Ancient Roman grave inscription +