vacuum delay feature, including updating the docs for Tom's recent
improvements. There is still more work to be done here: for example,
adding some more information on the practical use of cost-based
vacuum delay to the "maintenance" section would probably be a good
idea.
Make btree index creation and initial validation of foreign-key constraints
use maintenance_work_mem rather than work_mem as their memory limit.
Add some code to guc.c to allow these variables to be referenced by their
old names in SHOW and SET commands, for backwards compatibility.
that it's good to join where there are join clauses rather than where there
are not. Also enable it to generate bushy plans at need, so that it doesn't
fail in the presence of multiple IN clauses containing sub-joins. These
changes appear to improve the behavior enough that we can substantially reduce
the default pool size and generations count, thereby decreasing the runtime,
and yet get as good or better plans as we were getting in 7.4. Consequently,
adjust the default GEQO parameters. I also modified the way geqo_effort is
used so that it affects both population size and number of generations;
it's now useful as a single control to adjust the GEQO runtime-vs-plan-quality
tradeoff. Bump geqo_threshold to 12, since even with these changes GEQO
seems to be slower than the regular planner at 11 relations.
default value for geqo_effort is supposed to be 40, not 1. The actual
'genetic' component of the GEQO algorithm has been practically disabled
since 7.1 because of this mistake. Improve documentation while at it.
intended to allow application authors to insulate themselves from
changes to the default value of 'default_with_oids' in future releases
of PostgreSQL.
This patch also fixes a bug in the earlier implementation of the
'default_with_oids' GUC variable: code in gram.y should not examine
the value of GUC variables directly due to synchronization issues.
proposal for eventually deprecating OIDs on user tables that I posted
earlier to pgsql-hackers. pg_dump now always specifies WITH OIDS or
WITHOUT OIDS when dumping a table. The documentation has been updated.
Neil Conway
> only think to look at sort_mem if they already had a clue. It should
> be mentioned under bulk data load (in performance tips chapter)
Attached is a doc patch that does this. The way I've worded it may not
be the best, though.
Neil Conway
of function bodies is done at CREATE FUNCTION time. This is normally
true but can be set false to avoid problems with forward references,
wrong schema search path, etc. This is just the backend patch, still
need to adjust pg_dump to make use of it.
sequence every time it's called is bogus --- it interferes with user
control over the seed, and actually decreases randomness overall
(because a seed based on time(NULL) is pretty predictable). If you really
want a reproducible result from geqo, do 'set seed = 0' before planning
a query.
heuristic determination of day vs month in date/time input. Add the
ability to specify that input is interpreted as yy-mm-dd order (which
formerly worked, but only for yy greater than 31). DateStyle's input
component now has the preferred spellings DMY, MDY, or YMD; the older
keywords European and US are now aliases for the first two of these.
Per recent discussions on pgsql-general.
>>ISTM that "source" is worth knowing.
>
> Hm, possibly. Any other opinions?
This version has the seven fields I proposed, including "source". Here's
an example that shows why I think it's valuable:
regression=# \x
Expanded display is on.
regression=# select * from pg_settings where name = 'enable_seqscan';
-[ RECORD 1 ]-----------
name | enable_seqscan
setting | on
context | user
vartype | bool
source | default
min_val |
max_val |
regression=# update pg_settings set setting = 'off' where name =
'enable_seqscan';
-[ RECORD 1 ]---
set_config | off
regression=# select * from pg_settings where name = 'enable_seqscan';
-[ RECORD 1 ]-----------
name | enable_seqscan
setting | off
context | user
vartype | bool
source | session
min_val |
max_val |
regression=# alter user postgres set enable_seqscan to 'off';
ALTER USER
(log out and then back in again)
regression=# \x
Expanded display is on.
regression=# select * from pg_settings where name = 'enable_seqscan';
-[ RECORD 1 ]-----------
name | enable_seqscan
setting | off
context | user
vartype | bool
source | user
min_val |
max_val |
In the first case, enable_seqscan is set to its default value. After
setting it to off, it is obvious that the value has been changed for the
session only. In the third case, you can see that the value has been set
specifically for the user.
Joe Conway
and 100 respectively, if the platform will allow it. initdb selects
values that are not too large to allow the postmaster to start, and
places these values in the installed postgresql.conf file. This allows
us to continue to start up out-of-the-box on platforms with small SHMMAX,
while having somewhat-realistic default settings on platforms with
reasonable SHMMAX. Per recent pghackers discussion.
Neil Conway
Bruce Momjian
Jan Wieck
Tom Lane
Joe Conway
Peter Eisentraut
PostgreSQL Daemon