Waiting for 9.6 – Allow per-tablespace effective_io_concurrency

On 8th of September, Alvaro Herrera committed patch:

Allow per-tablespace effective_io_concurrency
 
Per discussion, nowadays it is possible to have tablespaces that have
wildly different I/O characteristics from others.  Setting different
effective_io_concurrency parameters for those has been measured to
improve performance.
 
Author: Julien Rouhaud
Reviewed by: Andres Freund

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Waiting for 9.6 – Allow usage of huge maintenance_work_mem for GIN build.

On 2nd of September, Teodor Sigaev committed patch:

Allow usage of huge maintenance_work_mem for GIN build.
 
Currently, in-memory posting list during GIN build process is limited 1GB
because of using repalloc. The patch replaces call of repalloc to repalloc_huge.
It increases limit of posting list from 180 millions
(1GB / sizeof(ItemPointerData)) to 4 billions limited by maxcount/count fields
in GinEntryAccumulator and subsequent calls. Check added.
 
Also, fix accounting of allocatedMemory during build to prevent integer
overflow with maintenance_work_mem > 4GB.
 
Robert Abraham <robert.abraham86@googlemail.com> with additions by me

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Waiting for 9.6 – Add IF NOT EXISTS processing to ALTER TABLE ADD COLUMN

On 30th of July, Andrew Dunstan committed patch:

Add IF NOT EXISTS processing to ALTER TABLE ADD COLUMN
 
Fabrízio de Royes Mello, reviewed by Payal Singh, Alvaro Herrera and
Michael Paquier.

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Waiting for 9.6 – Add new function pg_notification_queue_usage.

On 17th of July, Robert Haas committed patch:

Add new function pg_notification_queue_usage.
 
This tells you what fraction of NOTIFY's queue is currently filled.
 
Brendan Jurd, reviewed by Merlin Moncure and Gurjeet Singh.  A few
further tweaks by me.

Continue reading Waiting for 9.6 – Add new function pg_notification_queue_usage.

Waiting for 9.6 – Add psql PROMPT variable showing the pid of the connected to backend.

On 7th of July, Andres Freund committed patch:

Add psql PROMPT variable showing the pid of the connected to backend.
 
The substitution for the pid is %p.
 
Author: Julien Rouhaud
Discussion: <a href="http://git.postgresql.org/gitweb/?p=postgresql.git;a=object;h=116262CF971C844FB6E793F8809B51C6E99D48">116262CF971C844FB6E793F8809B51C6E99D48</a>@BPXM02GP.gisp.nec.co.jp

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Waiting for 9.6 – Add psql \ev and \sv commands for editing and showing view definitions.

On 3rd of July, Tom Lane committed patch:

Add psql \ev and \sv commands for editing and showing view definitions.
 
These are basically just like the \ef and \sf commands for functions.
 
Petr Korobeinikov, reviewed by Jeevan Chalke, some changes by me

Continue reading Waiting for 9.6 – Add psql \ev and \sv commands for editing and showing view definitions.

Partitioning – what? why? how?

Recently I noticed that more and more cases that I deal with could use some partitioning. And while theoretically most people know about it, it's definitely not a very well-understood feature, and sometimes people are scared of it.

So, I'll try to explain, to my best knowledge, what it is, why one would want to use it, and how to actually make it happen.

Continue reading Partitioning – what? why? how?

Filling in the blanks

Some time ago someone on irc asked interesting question. One that I couldn't answer then (didn't have an immediate idea, and didn't have time to spend on looking into it).

Now, I have some more time, and despite the fact that the person that had this problem no longer cares about it (he found some solution himself if I recall correctly), decided to look into it.

Continue reading Filling in the blanks