Subject: Better I/O throughput? (was Re: create tablespace - cannot run inside
 a transaction block)
To: pgsql-admin@lists.postgresql.org
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From: Ron <ronljohnsonjr@gmail.com>
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Date: Wed, 25 Sep 2019 14:40:35 -0500
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On 9/25/19 2:16 PM, Laurenz Albe wrote:
> On Wed, 2019-09-25 at 14:50 +0000, Pepe TD Vo wrote:
>> Normally, in Oracle we need to create database, tablespace then
>> username/schema and tables, objects, etc...
>>
>> is the procedure as same as in Postgres?  I see the login and schema
>> are totally different in Postgres.
> No, normally you don't create tablespaces in PostgreSQL.
> They are a few use cases for them, but not many.

Do I/O requests in the Linux kernel get "backlogged" when they all hit the 
same device?  Or would you get better throughput (or less latency) by 
spreading the load across multiple devices?

(A long-running synchronous IO request seems it would block everything 
behind it, whereas objects in tablespaces on different devices could still 
be queried.)

-- 
Angular momentum makes the world go 'round.