Re: increasing the default WAL segment size

David Steele <david@pgmasters.net>

From: David Steele <david@pgmasters.net>
To: Stephen Frost <sfrost@snowman.net>, Robert Haas <robertmhaas@gmail.com>
Cc: Beena Emerson <memissemerson@gmail.com>, tushar <tushar.ahuja@enterprisedb.com>, Prabhat Sahu <prabhat.sahu@enterprisedb.com>, Ashutosh Sharma <ashu.coek88@gmail.com>, Jim Nasby <Jim.Nasby@bluetreble.com>, Kuntal Ghosh <kuntalghosh.2007@gmail.com>, Andres Freund <andres@anarazel.de>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2017-03-22T19:24:58Z
Lists: pgsql-hackers
On 3/22/17 3:09 PM, Stephen Frost wrote:
> * Robert Haas (robertmhaas@gmail.com) wrote:
>> On Wed, Mar 22, 2017 at 1:49 PM, Stephen Frost <sfrost@snowman.net> wrote:
>>> Then perhaps we do need to be thinking of moving this to PG11 instead of
>>> exposing an option that users will start to use which will result in WAL
>>> naming that'll be confusing and inconsistent.  I certainly don't think
>>> it's a good idea to move forward exposing an option with a naming scheme
>>> that's agreed to be bad.
>>
>
> One of the reasons to go with the LSN is that we would actually be
> maintaining what happens when the WAL files are 16MB in size.
>
> David's initial expectation was this for 64MB WAL files:
>
> 000000010000000000000040
> 000000010000000000000080
> 0000000100000000000000CO
> 000000010000000100000000

This is the 1GB sequence, actually, but idea would be the same for 64MB 
files.

-- 
-David
david@pgmasters.net


Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Make WAL segment size configurable at initdb time.

  2. Perform only one ReadControlFile() during startup.

  3. Introduce BYTES unit for GUCs.

  4. Remove useless duplicate inclusions of system header files.

  5. Refactor other replication commands to use DestRemoteSimple.

  6. Add a SHOW command to the replication command language.

  7. Add a new DestReceiver for printing tuples without catalog access.

  8. Support fls().

  9. Extend yesterday's patch making BLCKSZ and RELSEG_SIZE configurable to also

  10. Commit the reasonably uncontroversial parts of J.R. Nield's PITR patch, to

  11. XLOG (also known as WAL -:)) Bootstrap/Startup/Shutdown.

  12. Transaction log manager core code.