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Commit Graph

1750 Commits

Author SHA1 Message Date
Alvaro Herrera
71a8a4f6e3 Add backtrace support for error reporting
Add some support for automatically showing backtraces in certain error
situations in the server.  Backtraces are shown on assertion failure;
also, a new setting backtrace_functions can be set to a list of C
function names, and all ereport()s and elog()s from the mentioned
functions will have backtraces generated.  Finally, the function
errbacktrace() can be manually added to an ereport() call to generate a
backtrace for that call.

Authors: Peter Eisentraut, Álvaro Herrera
Discussion: https://postgr.es/m//5f48cb47-bf1e-05b6-7aae-3bf2cd01586d@2ndquadrant.com
Discussion: https://postgr.es/m/CAMsr+YGL+yfWE=JvbUbnpWtrRZNey7hJ07+zT4bYJdVp4Szdrg@mail.gmail.com
2019-11-08 15:44:20 -03:00
Tomas Vondra
6e3e6cc0e8 Allow sampling of statements depending on duration
This allows logging a sample of statements, without incurring excessive
log traffic (which may impact performance).  This can be useful when
analyzing workloads with lots of short queries.

The sampling is configured using two new GUC parameters:

 * log_min_duration_sample - minimum required statement duration

 * log_statement_sample_rate - sample rate (0.0 - 1.0)

Only statements with duration exceeding log_min_duration_sample are
considered for sampling. To enable sampling, both those GUCs have to
be set correctly.

The existing log_min_duration_statement GUC has a higher priority, i.e.
statements with duration exceeding log_min_duration_statement will be
always logged, irrespectedly of how the sampling is configured. This
means only configurations

  log_min_duration_sample < log_min_duration_statement

do actually sample the statements, instead of logging everything.

Author: Adrien Nayrat
Reviewed-by: David Rowley, Vik Fearing, Tomas Vondra
Discussion: https://postgr.es/m/bbe0a1a8-a8f7-3be2-155a-888e661cc06c@anayrat.info
2019-11-06 19:11:07 +01:00
Andres Freund
01368e5d9d Split all OBJS style lines in makefiles into one-line-per-entry style.
When maintaining or merging patches, one of the most common sources
for conflicts are the list of objects in makefiles. Especially when
the split across lines has been changed on both sides, which is
somewhat common due to attempting to stay below 80 columns, those
conflicts are unnecessarily laborious to resolve.

By splitting, and alphabetically sorting, OBJS style lines into one
object per line, conflicts should be less frequent, and easier to
resolve when they still occur.

Author: Andres Freund
Discussion: https://postgr.es/m/20191029200901.vww4idgcxv74cwes@alap3.anarazel.de
2019-11-05 14:41:07 -08:00
Tom Lane
22f6f2c1cc Improve management of statement timeouts.
Commit f8e5f156b added private state in postgres.c to track whether
a statement timeout is running.  This seems like bad design to me;
timeout.c's private state should be the single source of truth about
that.  We already fixed one bug associated with failure to keep those
states in sync (cf. be42015fc), and I've got little faith that we
won't find more in future.  So get rid of postgres.c's local variable
by exposing a way to ask timeout.c whether a timeout is running.
(Obviously, such an inquiry is subject to race conditions, but it
seems fine for the purpose at hand.)

To make get_timeout_active() as cheap as possible, add a flag in
the per-timeout struct showing whether that timeout is active.
This allows some small savings elsewhere in timeout.c, mainly
elimination of unnecessary searches of the active_timeouts array.

While at it, fix enable_statement_timeout to not call disable_timeout
when statement_timeout is 0 and the timeout is not running.  This
avoids a useless deschedule-and-reschedule-timeouts cycle, which
represents a significant savings (at least one kernel call) when
there is any other active timeout.  Right now, there usually isn't,
but there are proposals around to change that.

Discussion: https://postgr.es/m/16035-456e6e69ebfd4374@postgresql.org
2019-10-25 11:41:16 -04:00
Thomas Munro
3c8c55dd54 When restoring GUCs in parallel workers, show an error context.
Otherwise it can be hard to see where an error is coming from, when
the parallel worker sets all the GUCs that it received from the
leader.  Bug #15726.  Back-patch to 9.5, where RestoreGUCState()
appeared.

Reported-by: Tiago Anastacio
Reviewed-by: Daniel Gustafsson, Tom Lane
Discussion: https://postgr.es/m/15726-6d67e4fa14f027b3%40postgresql.org
2019-10-17 13:47:01 +13:00
Peter Eisentraut
887248e97e Message style fixes 2019-09-23 13:38:39 +02:00
Tom Lane
6e42130568 Reject empty names and recursion in config-file include directives.
An empty file name or subdirectory name leads join_path_components() to
just produce the parent directory name, which leads to weird failures or
recursive inclusions.  Let's throw a specific error for that.  It takes
only slightly more code to detect all-blank names, so do so.

Also, detect direct recursion, ie a file calling itself.  As coded
this will also detect recursion via "include_dir '.'", which is
perhaps more likely than explicitly including the file itself.

Detecting indirect recursion would require API changes for guc-file.l
functions, which seems not worth it since extensions might call them.
The nesting depth limit will catch such cases eventually, just not
with such an on-point error message.

In passing, adjust the example usages in postgresql.conf.sample
to perhaps eliminate the problem at the source: there's no reason
for the examples to suggest that an empty value is valid.

Per a trouble report from Brent Bates.  Back-patch to 9.5; the
issue is old, but the code in 9.4 is enough different that the
patch doesn't apply easily, and it doesn't seem worth the trouble
to fix there.

Ian Barwick and Tom Lane

Discussion: https://postgr.es/m/8c8bcbca-3bd9-dc6e-8986-04a5abdef142@2ndquadrant.com
2019-08-27 14:44:26 -04:00
Andres Freund
f7db0ac7d5 Add default_table_access_method to postgresql.conf.sample.
Reported-By: Heikki Linnakangas
Author: Michael Paquier
Discussion: https://postgr.es/m/d6ffbebb-a0d2-181c-811d-b029b2225ed7@iki.fi
Backpatch: 12-, where pluggable table access methods were introduced
2019-08-16 15:24:22 -07:00
Tom Lane
f1bf619acd Fix ALTER SYSTEM to cope with duplicate entries in postgresql.auto.conf.
ALTER SYSTEM itself normally won't make duplicate entries (although
up till this patch, it was possible to confuse it by writing case
variants of a GUC's name).  However, if some external tool has appended
entries to the file, that could result in duplicate entries for a single
GUC name.  In such a situation, ALTER SYSTEM did exactly the wrong thing,
because it replaced or removed only the first matching entry, leaving
the later one(s) still there and hence still determining the active value.

This patch fixes that by making ALTER SYSTEM sweep through the file and
remove all matching entries, then (if not ALTER SYSTEM RESET) append the
new setting to the end.  This means entries will be in order of last
setting rather than first setting, but that shouldn't hurt anything.

Also, make the comparisons case-insensitive so that the right things
happen if you do, say, ALTER SYSTEM SET "TimeZone" = 'whatever'.

This has been broken since ALTER SYSTEM was invented, so back-patch
to all supported branches.

Ian Barwick, with minor mods by me

Discussion: https://postgr.es/m/aed6cc9f-98f3-2693-ac81-52bb0052307e@2ndquadrant.com
2019-08-14 15:09:42 -04:00
Michael Paquier
66bde49d96 Fix inconsistencies and typos in the tree, take 10
This addresses some issues with unnecessary code comments, fixes various
typos in docs and comments, and removes some orphaned structures and
definitions.

Author: Alexander Lakhin
Discussion: https://postgr.es/m/9aabc775-5494-b372-8bcb-4dfc0bd37c68@gmail.com
2019-08-13 13:53:41 +09:00
Tomas Vondra
75506195da Revert "Add log_statement_sample_rate parameter"
This reverts commit 88bdbd3f74.

As committed, statement sampling used the existing duration threshold
(log_min_duration_statement) when decide which statements to sample.
The issue is that even the longest statements are subject to sampling,
and so may not end up logged. An improvement was proposed, introducing
a second duration threshold, but it would not be backwards compatible.
So we've decided to revert this feature - the separate threshold should
be part of the feature itself.

Discussion: https://postgr.es/m/CAFj8pRDS8tQ3Wviw9%3DAvODyUciPSrGeMhJi_WPE%2BEB8%2B4gLL-Q%40mail.gmail.com
2019-08-04 23:38:27 +02:00
Bruce Momjian
ba09342518 Adjust ssl_ciphers to be specific to OpenSSL
Syntax is OpenSSL-specific, so only use it for OpenSSL.

Discussion: https://postgr.es/m/8232E273-7B25-47F4-B0E7-3D4264106F82@yesql.se

Author: Daniel Gustafsson

Backpatch-through: head
2019-07-08 19:39:48 -04:00
Michael Paquier
6b8548964b Fix inconsistencies in the code
This addresses a couple of issues in the code:
- Typos and inconsistencies in comments and function declarations.
- Removal of unreferenced function declarations.
- Removal of unnecessary compile flags.
- A cleanup error in regressplans.sh.

Author: Alexander Lakhin
Discussion: https://postgr.es/m/0c991fdf-2670-1997-c027-772a420c4604@gmail.com
2019-07-08 13:15:09 +09:00
Thomas Munro
e8fdcacc6c Improve comment in postgresql.conf.sample.
The Unix manual section that "man tcp" appears in varies, so let's
just leave it out of the command to run.
2019-07-05 21:03:51 +12:00
Tom Lane
9e1c9f9594 pgindent run prior to branching v12.
pgperltidy and reformat-dat-files too, though the latter didn't
find anything to change.
2019-07-01 12:37:52 -04:00
Peter Eisentraut
21f428ebde Don't call data type input functions in GUC check hooks
Instead of calling pg_lsn_in() in check_recovery_target_lsn and
timestamptz_in() in check_recovery_target_time, reorganize the
respective code so that we don't raise any errors in the check hooks.
The previous code tried to use PG_TRY/PG_CATCH to handle errors in a
way that is not safe, so now the code contains no ereport() calls and
can operate safely within the GUC error handling system.

Moreover, since the interpretation of the recovery_target_time string
may depend on the time zone, we cannot do the final processing of that
string until all the GUC processing is done.  Instead,
check_recovery_target_time() now does some parsing for syntax
checking, but the actual conversion to a timestamptz value is done
later in the recovery code that uses it.

Reported-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://www.postgresql.org/message-id/flat/20190611061115.njjwkagvxp4qujhp%40alap3.anarazel.de
2019-06-30 10:27:43 +02:00
Amit Kapila
9679345f3c Fix typos.
Reported-by: Alexander Lakhin
Author: Alexander Lakhin
Reviewed-by: Amit Kapila and Tom Lane
Discussion: https://postgr.es/m/7208de98-add8-8537-91c0-f8b089e2928c@gmail.com
2019-05-26 18:28:18 +05:30
Tom Lane
8255c7a5ee Phase 2 pgindent run for v12.
Switch to 2.1 version of pg_bsd_indent.  This formats
multiline function declarations "correctly", that is with
additional lines of parameter declarations indented to match
where the first line's left parenthesis is.

Discussion: https://postgr.es/m/CAEepm=0P3FeTXRcU5B2W3jv3PgRVZ-kGUXLGfd42FFhUROO3ug@mail.gmail.com
2019-05-22 13:04:48 -04:00
Tom Lane
be76af171c Initial pgindent run for v12.
This is still using the 2.0 version of pg_bsd_indent.
I thought it would be good to commit this separately,
so as to document the differences between 2.0 and 2.1 behavior.

Discussion: https://postgr.es/m/16296.1558103386@sss.pgh.pa.us
2019-05-22 12:55:34 -04:00
Etsuro Fujita
7d9eca59cf Fix typo. 2019-05-14 16:05:37 +09:00
Alvaro Herrera
9f8b717a80 Message style fixes 2019-04-30 10:33:37 -04:00
Bruce Momjian
fb9c475597 postgresql.conf.sample: add proper defaults for include actions
Previously, include actions include_dir, include_if_exists, and include
listed commented-out values which were not the defaults, which is
inconsistent with other entries.  Instead, replace them with '', which
is the default value.

Reported-by: Emanuel Araújo

Discussion: https://postgr.es/m/CAMuTAkYMx6Q27wpELDR3_v9aG443y7ZjeXu15_+1nGUjhMWOJA@mail.gmail.com

Backpatch-through: 9.4
2019-04-17 18:12:10 -04:00
Michael Paquier
249d649996 Add support TCP user timeout in libpq and the backend server
Similarly to the set of parameters for keepalive, a connection parameter
for libpq is added as well as a backend GUC, called tcp_user_timeout.

Increasing the TCP user timeout is useful to allow a connection to
survive extended periods without end-to-end connection, and decreasing
it allows application to fail faster.  By default, the parameter is 0,
which makes the connection use the system default, and follows a logic
close to the keepalive parameters in its handling.  When connecting
through a Unix-socket domain, the parameters have no effect.

Author: Ryohei Nagaura
Reviewed-by: Fabien Coelho, Robert Haas, Kyotaro Horiguchi, Kirk
Jamison, Mikalai Keida, Takayuki Tsunakawa, Andrei Yahorau
Discussion: https://postgr.es/m/EDA4195584F5064680D8130B1CA91C45367328@G01JPEXMBYT04
2019-04-06 15:23:37 +09:00
Tomas Vondra
ea569d64ac Add SETTINGS option to EXPLAIN, to print modified settings.
Query planning is affected by a number of configuration options, and it
may be crucial to know which of those options were set to non-default
values.  With this patch you can say EXPLAIN (SETTINGS ON) to include
that information in the query plan.  Only options affecting planning,
with values different from the built-in default are printed.

This patch also adds auto_explain.log_settings option, providing the
same capability in auto_explain module.

Author: Tomas Vondra
Reviewed-by: Rafia Sabih, John Naylor
Discussion: https://postgr.es/m/e1791b4c-df9c-be02-edc5-7c8874944be0@2ndquadrant.com
2019-04-04 00:04:31 +02:00
Alvaro Herrera
d1f04b96b9 Tweak docs for log_statement_sample_rate
Author: Justin Pryzby, partly after a suggestion from Masahiko Sawada
Discussion: https://postgr.es/m/20190328135918.GA27808@telsasoft.com
Discussion: https://postgr.es/m/CAD21AoB9+y8N4+Fan-ne-_7J5yTybPttxeVKfwUocKp4zT1vNQ@mail.gmail.com
2019-04-03 18:56:56 -03:00
Alvaro Herrera
799e220346 Log all statements from a sample of transactions
This is useful to obtain a view of the different transaction types in an
application, regardless of the durations of the statements each runs.

Author: Adrien Nayrat
Reviewed-by: Masahiko Sawada, Hayato Kuroda, Andres Freund
2019-04-03 18:43:59 -03:00
Thomas Munro
475861b261 Add wal_recycle and wal_init_zero GUCs.
On at least ZFS, it can be beneficial to create new WAL files every
time and not to bother zero-filling them.  Since it's not clear which
other filesystems might benefit from one or both of those things,
add individual GUCs to control those two behaviors independently and
make only very general statements in the docs.

Author: Jerry Jelinek, with some adjustments by Thomas Munro
Reviewed-by: Alvaro Herrera, Andres Freund, Tomas Vondra, Robert Haas and others
Discussion: https://postgr.es/m/CACPQ5Fo00QR7LNAcd1ZjgoBi4y97%2BK760YABs0vQHH5dLdkkMA%40mail.gmail.com
2019-04-02 14:37:14 +13:00
Peter Eisentraut
cc8d415117 Unified logging system for command-line programs
This unifies the various ad hoc logging (message printing, error
printing) systems used throughout the command-line programs.

Features:

- Program name is automatically prefixed.

- Message string does not end with newline.  This removes a common
  source of inconsistencies and omissions.

- Additionally, a final newline is automatically stripped, simplifying
  use of PQerrorMessage() etc., another common source of mistakes.

- I converted error message strings to use %m where possible.

- As a result of the above several points, more translatable message
  strings can be shared between different components and between
  frontends and backend, without gratuitous punctuation or whitespace
  differences.

- There is support for setting a "log level".  This is not meant to be
  user-facing, but can be used internally to implement debug or
  verbose modes.

- Lazy argument evaluation, so no significant overhead if logging at
  some level is disabled.

- Some color in the messages, similar to gcc and clang.  Set
  PG_COLOR=auto to try it out.  Some colors are predefined, but can be
  customized by setting PG_COLORS.

- Common files (common/, fe_utils/, etc.) can handle logging much more
  simply by just using one API without worrying too much about the
  context of the calling program, requiring callbacks, or having to
  pass "progname" around everywhere.

- Some programs called setvbuf() to make sure that stderr is
  unbuffered, even on Windows.  But not all programs did that.  This
  is now done centrally.

Soft goals:

- Reduces vertical space use and visual complexity of error reporting
  in the source code.

- Encourages more deliberate classification of messages.  For example,
  in some cases it wasn't clear without analyzing the surrounding code
  whether a message was meant as an error or just an info.

- Concepts and terms are vaguely aligned with popular logging
  frameworks such as log4j and Python logging.

This is all just about printing stuff out.  Nothing affects program
flow (e.g., fatal exits).  The uses are just too varied to do that.
Some existing code had wrappers that do some kind of print-and-exit,
and I adapted those.

I tried to keep the output mostly the same, but there is a lot of
historical baggage to unwind and special cases to consider, and I
might not always have succeeded.  One significant change is that
pg_rewind used to write all error messages to stdout.  That is now
changed to stderr.

Reviewed-by: Donald Dong <xdong@csumb.edu>
Reviewed-by: Arthur Zakirov <a.zakirov@postgrespro.ru>
Discussion: https://www.postgresql.org/message-id/flat/6a609b43-4f57-7348-6480-bd022f924310@2ndquadrant.com
2019-04-01 20:01:35 +02:00
Thomas Munro
2fc7af5e96 Add basic infrastructure for 64 bit transaction IDs.
Instead of inferring epoch progress from xids and checkpoints,
introduce a 64 bit FullTransactionId type and use it to track xid
generation.  This fixes an unlikely bug where the epoch is reported
incorrectly if the range of active xids wraps around more than once
between checkpoints.

The only user-visible effect of this commit is to correct the epoch
used by txid_current() and txid_status(), also visible with
pg_controldata, in those rare circumstances.  It also creates some
basic infrastructure so that later patches can use 64 bit
transaction IDs in more places.

The new type is a struct that we pass by value, as a form of strong
typedef.  This prevents the sort of accidental confusion between
TransactionId and FullTransactionId that would be possible if we
were to use a plain old uint64.

Author: Thomas Munro
Reported-by: Amit Kapila
Reviewed-by: Andres Freund, Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/CAA4eK1%2BMv%2Bmb0HFfWM9Srtc6MVe160WFurXV68iAFMcagRZ0dQ%40mail.gmail.com
2019-03-28 18:12:20 +13:00
Peter Eisentraut
893d6f8a1f Avoid casting away a const 2019-03-16 10:13:03 +01:00
Tom Lane
1a83a80a2f Allow fractional input values for integer GUCs, and improve rounding logic.
Historically guc.c has just refused examples like set work_mem = '30.1GB',
but it seems more useful for it to take that and round off the value to
some reasonable approximation of what the user said.  Just rounding to
the parameter's native unit would work, but it would lead to rather
silly-looking settings, such as 31562138kB for this example.  Instead
let's round to the nearest multiple of the next smaller unit (if any),
producing 30822MB.

Also, do the units conversion math in floating point and round to integer
(if needed) only at the end.  This produces saner results for inputs that
aren't exact multiples of the parameter's native unit, and removes another
difference in the behavior for integer vs. float parameters.

In passing, document the ability to use hex or octal input where it
ought to be documented.

Discussion: https://postgr.es/m/1798.1552165479@sss.pgh.pa.us
2019-03-11 19:13:55 -04:00
Tom Lane
d9c5e9629b Give up on testing guc.c's behavior for "infinity" inputs.
Further buildfarm testing shows that on the machines that are failing
ac75959cd's test case, what we're actually getting from strtod("-infinity")
is a syntax error (endptr == value) not ERANGE at all.  This test case
is not worth carrying two sets of expected output for, so just remove it,
and revert commit b212245f9's misguided attempt to work around the platform
dependency.

Discussion: https://postgr.es/m/E1h33xk-0001Og-Gs@gemulon.postgresql.org
2019-03-11 17:53:09 -04:00
Tom Lane
b212245f96 In guc.c, ignore ERANGE errors from strtod().
Instead, just proceed with the infinity or zero result that it should
return for overflow/underflow.  This avoids a platform dependency,
in that various versions of strtod are inconsistent about whether they
signal ERANGE for a value that's specified as infinity.

It's possible this won't be enough to remove the buildfarm failures
we're seeing from ac75959cd, in which case I'll take out the infinity
test case that commit added.  But first let's see if we can fix it.

Discussion: https://postgr.es/m/E1h33xk-0001Og-Gs@gemulon.postgresql.org
2019-03-11 11:25:26 -04:00
Tom Lane
cbccac371c Reduce the default value of autovacuum_vacuum_cost_delay to 2ms.
This is a better way to implement the desired change of increasing
autovacuum's default resource consumption.

Discussion: https://postgr.es/m/28720.1552101086@sss.pgh.pa.us
2019-03-10 15:16:21 -04:00
Tom Lane
52985e4fea Revert "Increase the default vacuum_cost_limit from 200 to 2000"
This reverts commit bd09503e63.

Per discussion, it seems like what we should do instead is to
reduce the default value of autovacuum_vacuum_cost_delay by the
same factor.  That's functionally equivalent as long as the
platform can accurately service the smaller delay request, which
should be true on anything released in the last 10 years or more.
And smaller, more-closely-spaced delays are better in terms of
providing a steady I/O load.

Discussion: https://postgr.es/m/28720.1552101086@sss.pgh.pa.us
2019-03-10 15:05:25 -04:00
Tom Lane
caf626b2cd Convert [autovacuum_]vacuum_cost_delay into floating-point GUCs.
This change makes it possible to specify sub-millisecond delays,
which work well on most modern platforms, though that was not true
when the cost-delay feature was designed.

To support this without breaking existing configuration entries,
improve guc.c to allow floating-point GUCs to have units.  Also,
allow "us" (microseconds) as an input/output unit for time-unit GUCs.
(It's not allowed as a base unit, at least not yet.)

Likewise change the autovacuum_vacuum_cost_delay reloption to be
floating-point; this forces a catversion bump because the layout of
StdRdOptions changes.

This patch doesn't in itself change the default values or allowed
ranges for these parameters, and it should not affect the behavior
for any already-allowed setting for them.

Discussion: https://postgr.es/m/1798.1552165479@sss.pgh.pa.us
2019-03-10 15:01:39 -04:00
Tom Lane
28a65fc360 Include GUC's unit, if it has one, in out-of-range error messages.
This should reduce confusion in cases where we've applied a units
conversion, so that the number being reported (and the quoted range
limits) are in some other units than what the user gave in the
setting we're rejecting.

Some of the changes here assume that float GUCs can have units,
which isn't true just yet, but will be shortly.

Discussion: https://postgr.es/m/3811.1552169665@sss.pgh.pa.us
2019-03-10 13:18:17 -04:00
Tom Lane
ac75959cdc Disallow NaN as a value for floating-point GUCs.
None of the code that uses GUC values is really prepared for them to
hold NaN, but parse_real() didn't have any defense against accepting
such a value.  Treat it the same as a syntax error.

I haven't attempted to analyze the exact consequences of setting any
of the float GUCs to NaN, but since they're quite unlikely to be good,
this seems like a back-patchable bug fix.

Note: we don't need an explicit test for +-Infinity because those will
be rejected by existing range checks.  I added a regression test for
that in HEAD, but not older branches because the spelling of the value
in the error message will be platform-dependent in branches where we
don't always use port/snprintf.c.

Discussion: https://postgr.es/m/1798.1552165479@sss.pgh.pa.us
2019-03-10 12:59:16 -04:00
Andres Freund
8586bf7ed8 tableam: introduce table AM infrastructure.
This introduces the concept of table access methods, i.e. CREATE
  ACCESS METHOD ... TYPE TABLE and
  CREATE TABLE ... USING (storage-engine).
No table access functionality is delegated to table AMs as of this
commit, that'll be done in following commits.

Subsequent commits will incrementally abstract table access
functionality to be routed through table access methods. That change
is too large to be reviewed & committed at once, so it'll be done
incrementally.

Docs will be updated at the end, as adding them incrementally would
likely make them less coherent, and definitely is a lot more work,
without a lot of benefit.

Table access methods are specified similar to index access methods,
i.e. pg_am.amhandler returns, as INTERNAL, a pointer to a struct with
callbacks. In contrast to index AMs that struct needs to live as long
as a backend, typically that's achieved by just returning a pointer to
a constant struct.

Psql's \d+ now displays a table's access method. That can be disabled
with HIDE_TABLEAM=true, which is mainly useful so regression tests can
be run against different AMs.  It's quite possible that this behaviour
still needs to be fine tuned.

For now it's not allowed to set a table AM for a partitioned table, as
we've not resolved how partitions would inherit that. Disallowing
allows us to introduce, if we decide that's the way forward, such a
behaviour without a compatibility break.

Catversion bumped, to add the heap table AM and references to it.

Author: Haribabu Kommi, Andres Freund, Alvaro Herrera, Dimitri Golgov and others
Discussion:
    https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
    https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
    https://postgr.es/m/20190107235616.6lur25ph22u5u5av@alap3.anarazel.de
    https://postgr.es/m/20190304234700.w5tmhducs5wxgzls@alap3.anarazel.de
2019-03-06 09:54:38 -08:00
Andrew Dunstan
bd09503e63 Increase the default vacuum_cost_limit from 200 to 2000
The original 200 default value was set back in f425b605f4 when the cost
delay settings were first added.  Hardware has improved quite a bit since
then and we've also made improvements such as sorting buffers during
checkpoints (9cd00c457e) which should result in less random writes.

This low default value was reportedly causing problems with badly
configured servers and in the absence of a native method to remove
excessive bloat from tables without incurring an AccessExclusiveLock, this
often made cleaning up the damage caused by badly configured auto-vacuums
difficult.

It seems more likely that someone will notice that auto-vacuum is running
too quickly than too slowly, so let's go all out and multiple the default
value for the setting by 10.  With the default vacuum_cost_page_dirty and
autovacuum_vacuum_cost_delay (assuming a page size of 8192 bytes), this
allows autovacuum a theoretical maximum dirty write rate of around 39MB/s
instead of just 3.9MB/s.

Author: David Rowley

Discussion: https://postgr.es/m/CAKJS1f_YbXC2qTMPyCbmsPiKvZYwpuQNQMohiRXLj1r=8_rYvw@mail.gmail.com
2019-03-06 09:10:12 -05:00
Michael Paquier
b3a156858a Improve documentation of data_sync_retry
Reflecting an updated parameter value requires a server restart, which
was not mentioned in the documentation and in postgresql.conf.sample.

Reported-by: Thomas Poty
Discussion: https://postgr.es/m/15659-0cd812f13027a2d8@postgresql.org
2019-02-28 11:02:11 +09:00
Andrew Gierth
02ddd49932 Change floating-point output format for improved performance.
Previously, floating-point output was done by rounding to a specific
decimal precision; by default, to 6 or 15 decimal digits (losing
information) or as requested using extra_float_digits. Drivers that
wanted exact float values, and applications like pg_dump that must
preserve values exactly, set extra_float_digits=3 (or sometimes 2 for
historical reasons, though this isn't enough for float4).

Unfortunately, decimal rounded output is slow enough to become a
noticable bottleneck when dealing with large result sets or COPY of
large tables when many floating-point values are involved.

Floating-point output can be done much faster when the output is not
rounded to a specific decimal length, but rather is chosen as the
shortest decimal representation that is closer to the original float
value than to any other value representable in the same precision. The
recently published Ryu algorithm by Ulf Adams is both relatively
simple and remarkably fast.

Accordingly, change float4out/float8out to output shortest decimal
representations if extra_float_digits is greater than 0, and make that
the new default. Applications that need rounded output can set
extra_float_digits back to 0 or below, and take the resulting
performance hit.

We make one concession to portability for systems with buggy
floating-point input: we do not output decimal values that fall
exactly halfway between adjacent representable binary values (which
would rely on the reader doing round-to-nearest-even correctly). This
is known to be a problem at least for VS2013 on Windows.

Our version of the Ryu code originates from
https://github.com/ulfjack/ryu/ at commit c9c3fb1979, but with the
following (significant) modifications:

 - Output format is changed to use fixed-point notation for small
   exponents, as printf would, and also to use lowercase 'e', a
   minimum of 2 exponent digits, and a mandatory sign on the exponent,
   to keep the formatting as close as possible to previous output.

 - The output of exact midpoint values is disabled as noted above.

 - The integer fast-path code is changed somewhat (since we have
   fixed-point output and the upstream did not).

 - Our project style has been largely applied to the code with the
   exception of C99 declaration-after-statement, which has been
   retained as an exception to our present policy.

 - Most of upstream's debugging and conditionals are removed, and we
   use our own configure tests to determine things like uint128
   availability.

Changing the float output format obviously affects a number of
regression tests. This patch uses an explicit setting of
extra_float_digits=0 for test output that is not expected to be
exactly reproducible (e.g. due to numerical instability or differing
algorithms for transcendental functions).

Conversions from floats to numeric are unchanged by this patch. These
may appear in index expressions and it is not yet clear whether any
change should be made, so that can be left for another day.

This patch assumes that the only supported floating point format is
now IEEE format, and the documentation is updated to reflect that.

Code by me, adapting the work of Ulf Adams and other contributors.

References:
https://dl.acm.org/citation.cfm?id=3192369

Reviewed-by: Tom Lane, Andres Freund, Donald Dong
Discussion: https://postgr.es/m/87r2el1bx6.fsf@news-spur.riddles.org.uk
2019-02-13 15:20:33 +00:00
Peter Eisentraut
37d9916020 More unconstify use
Replace casts whose only purpose is to cast away const with the
unconstify() macro.

Discussion: https://www.postgresql.org/message-id/flat/53a28052-f9f3-1808-fed9-460fd43035ab%402ndquadrant.com
2019-02-13 11:50:16 +01:00
Michael Paquier
ea92368cd1 Move max_wal_senders out of max_connections for connection slot handling
Since its introduction, max_wal_senders is counted as part of
max_connections when it comes to define how many connection slots can be
used for replication connections with a WAL sender context.  This can
lead to confusion for some users, as it could be possible to block a
base backup or replication from happening because other backend sessions
are already taken for other purposes by an application, and
superuser-only connection slots are not a correct solution to handle
that case.

This commit makes max_wal_senders independent of max_connections for its
handling of PGPROC entries in ProcGlobal, meaning that connection slots
for WAL senders are handled using their own free queue, like autovacuum
workers and bgworkers.

One compatibility issue that this change creates is that a standby now
requires to have a value of max_wal_senders at least equal to its
primary.  So, if a standby created enforces the value of
max_wal_senders to be lower than that, then this could break failovers.
Normally this should not be an issue though, as any settings of a
standby are inherited from its primary as postgresql.conf gets normally
copied as part of a base backup, so parameters would be consistent.

Author: Alexander Kukushkin
Reviewed-by: Kyotaro Horiguchi, Petr Jelínek, Masahiko Sawada, Oleksii
Kliukin
Discussion: https://postgr.es/m/CAFh8B=nBzHQeYAu0b8fjK-AF1X4+_p6GRtwG+cCgs6Vci2uRuQ@mail.gmail.com
2019-02-12 10:07:56 +09:00
Peter Eisentraut
13b89f96d0 Allow some recovery parameters to be changed with reload
Change

archive_cleanup_command
promote_trigger_file
recovery_end_command
recovery_min_apply_delay

from PGC_POSTMASTER to PGC_SIGHUP.  This did not require any further
changes.

Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://www.postgresql.org/message-id/flat/ca28011a-cfaa-565c-d622-c1907c33ecf7%402ndquadrant.com
2019-02-07 08:34:48 +01:00
Thomas Munro
f1bebef60e Add shared_memory_type GUC.
Since 9.3 we have used anonymous shared mmap for our main shared memory
region, except in EXEC_BACKEND builds.  Provide a GUC so that users
can opt for System V shared memory once again, like in 9.2 and earlier.

A later patch proposes to add huge/large page support for AIX, which
requires System V shared memory and provided the motivation to revive
this possibility.  It may also be useful on some BSDs.

Author: Andres Freund (revived and documented by Thomas Munro)
Discussion: https://postgr.es/m/HE1PR0202MB28126DB4E0B6621CC6A1A91286D90%40HE1PR0202MB2812.eurprd02.prod.outlook.com
Discussion: https://postgr.es/m/2AE143D2-87D3-4AD1-AC78-CE2258230C05%40FreeBSD.org
2019-02-03 12:47:26 +01:00
Tom Lane
f09346a9c6 Refactor planner's header files.
Create a new header optimizer/optimizer.h, which exposes just the
planner functions that can be used "at arm's length", without need
to access Paths or the other planner-internal data structures defined
in nodes/relation.h.  This is intended to provide the whole planner
API seen by most of the rest of the system; although FDWs still need
to use additional stuff, and more thought is also needed about just
what selfuncs.c should rely on.

The main point of doing this now is to limit the amount of new
#include baggage that will be needed by "planner support functions",
which I expect to introduce later, and which will be in relevant
datatype modules rather than anywhere near the planner.

This commit just moves relevant declarations into optimizer.h from
other header files (a couple of which go away because everything
got moved), and adjusts #include lists to match.  There's further
cleanup that could be done if we want to decide that some stuff
being exposed by optimizer.h doesn't belong in the planner at all,
but I'll leave that for another day.

Discussion: https://postgr.es/m/11460.1548706639@sss.pgh.pa.us
2019-01-29 15:48:51 -05:00
Andres Freund
e0c4ec0728 Replace uses of heap_open et al with the corresponding table_* function.
Author: Andres Freund
Discussion: https://postgr.es/m/20190111000539.xbv7s6w7ilcvm7dp@alap3.anarazel.de
2019-01-21 10:51:37 -08:00
Andres Freund
111944c5ee Replace heapam.h includes with {table, relation}.h where applicable.
A lot of files only included heapam.h for relation_open, heap_open etc
- replace the heapam.h include in those files with the narrower
header.

Author: Andres Freund
Discussion: https://postgr.es/m/20190111000539.xbv7s6w7ilcvm7dp@alap3.anarazel.de
2019-01-21 10:51:37 -08:00
Andres Freund
de66987adb Re-add default_with_oids GUC to avoid breaking old dump files.
After 578b229718 / the removal of WITH OIDS support, older dump files
containing
    SET default_with_oids = false;
either report unnecessary errors (as the subsequent tables have no
oids) or even fail to restore entirely (when using transaction mode).
To avoid that, re-add the GUC, but don't allow setting it to true.

Per complaint from Tom Lane.

Author: Amit Khandekar, editorialized by me
Discussion: https://postgr.es/m/CAJ3gD9dZyxrtL0rJfoNoOj6v7fJSDaXBngi9wy5XU8m-ioXhAA@mail.gmail.com
2019-01-14 15:30:24 -08:00