Re: pgsql: Make WAL segment size configurable at initdb time.

David Steele <david@pgmasters.net>

From: David Steele <david@pgmasters.net>
To: Michael Paquier <michael@paquier.xyz>, Andres Freund <andres@anarazel.de>
Cc: pgsql-committers@postgresql.org
Date: 2018-09-21T11:44:06Z
Lists: pgsql-hackers
On 9/21/18 12:53 AM, Michael Paquier wrote:
> On Thu, Sep 20, 2018 at 06:23:54PM -0700, Andres Freund wrote:
>> 16*M*B, right?  If so, that's normal - pg_settings just reports the
>> values in the underlying unit - which is XLOG_BLCKSZ, compile-time
>> defaulting to 8KB. 8192 * 2048 = 16MB.  That's the same in various other
>> settings.
> 
> Would it bring less confusion if we append something like "When querying
> pg_settings"?  I can see David's point the current phrasing is
> confusing: we don't know if this comes from pg_settings or from SHOW.
> It obviously refers to the former, but one can understand that it refers
> to the latter.
> 
> A second parameter in config.sgml where this formulation is used is
> segment_size.

That's why I used a default of 16MB instead of the byte value, because
segment_size used 1GB instead of the byte value.

-- 
-David
david@pgmasters.net

Commits

  1. docs: Adapt wal_segment_size docs to fc49e24fa69.

  2. Fix s/intidb/initdb/ typo.

  3. Make WAL segment size configurable at initdb time.