enabled. Bypassing the kernel cache is counter-productive in that case,
because the archiver/walsender process will read from the WAL file
soon after it's written, and if it's not cached the read will cause
a physical read, eating I/O bandwidth available on the WAL drive.

Also, walreceiver process does unaligned writes, so disable O_DIRECT
in walreceiver process for that reason too.

Erik Rijkers. Patch by Andres Freund.

segment of XLOG_BACKUP_END record even if the the record is placed
at a segment boundary. Furthermore the previous implementation could
return nonexistent segment file name when the boundary is in segments
that has "FE" suffix; We never use segments with "FF" suffix.

Backpatch to 8.0, where hot backup was introduced.

Reported by Fujii Masao.

old memory context in plpython.  Before only one of them was marked
volatile, but per report from Zdenek Kotala, some compilers do the
wrong thing here.

ArrayRef expressions that are not in the immediate context of an INSERT or
UPDATE targetlist.  Such cases never arise in stored rules, so ruleutils.c
hadn't tried to handle them.  However, they do occur in the targetlists of
plans derived from such statements, and now that EXPLAIN VERBOSE tries to
print targetlists, we need some way to deal with the case.

I chose to represent an assignment ArrayRef as "array[subscripts] := source",
which is fairly reasonable and doesn't omit any information.  However,
FieldStore is problematic because the planner will fold multiple assignments
to fields of the same composite column into one FieldStore, resulting in a
structure that is hard to understand at all, let alone display comprehensibly.
So in that case I punted and just made it print the source expression(s).

Backpatch to 8.4 --- the lack of functionality exists in older releases,
but doesn't seem to be important for lack of anything that would call it.

being assigned to, in case the expression to be assigned is a FieldStore that
would need to modify that value.  The need for this was foreseen some time
ago, but not implemented then because we did not have arrays of composites.
Now we do, but the point evidently got overlooked in that patch.  Net result
is that updating a field of an array element doesn't work right, as
illustrated if you try the new regression test on an unpatched backend.
Noted while experimenting with EXPLAIN VERBOSE, which has also got some issues
in this area.

Backpatch to 8.3, where arrays of composites were introduced.

returns if no data is immediately available. Patch by me with numerous
fixes from Fujii Masao and Magnus Hagander.

Reported by James William Pye.

is aborted, if they were created within the failed xact.  This prevents
ExecutorEnd from being run on them, which is a good idea because they may
contain references to tables or other objects that no longer exist.
In particular this is hazardous when auto_explain is active, but it's
really rather surprising that nobody has seen an issue with this before.
I'm back-patching this to 8.4, since that's the first version that contains
auto_explain or an ExecutorEnd hook, but I wonder whether we shouldn't
back-patch further.

a separate archive entry for each BLOB, and use pg_dump's standard methods
for dealing with its ownership, ACL if any, and comment if any.  This means
that switches like --no-owner and --no-privileges do what they're supposed
to.  Preliminary testing says that performance is still reasonable even
with many blobs, though we'll have to see how that shakes out in the field.

KaiGai Kohei, revised by me

Oversight in my changes to cope with possible errors during message
processing; spotted by Joachim Wieland.

Thom Brown

Use a fatal warning check with what looks like a more portable error message. Error noticed by Tom and buildfarm member kite.

(hope I got 'em all).  Per discussion, this release will be 9.0 not 8.5.

Newly supported syntax are:
  - ALTER {TABLE|INDEX|TABLESPACE} {SET|RESET} with options
  - ALTER TABLE ALTER COLUMN {SET|RESET} with options
  - ALTER TABLE ALTER COLUMN SET STORAGE
  - CREATE INDEX CONCURRENTLY
  - CREATE INDEX ON (without name)
  - CREATE INDEX ... USING with pg_am.amname instead of hard-corded names
  - CREATE TRIGGER with events
  - DROP AGGREGATE function with arguments

all the values derived from oldestXid, not just that field.  Brain fade in
one of my patches associated with flat file removal, exposed by a report
from Fujii Masao.

With this change, xidVacLimit should always be valid, so remove a couple of
bits of complexity associated with the previous assumption that sometimes
it wouldn't get set right away.

NAMEDATALEN, so this code doesn't go nuts with smaller than default
BLCKSZ or larger than default NAMEDATALEN.  The standard value is
still exactly 8000.

In addition, add support for a "payload" string to be passed along with
each notify event.

This implementation should be significantly more efficient than the old one,
and is also more compatible with Hot Standby usage.  There is not yet any
facility for HS slaves to receive notifications generated on the master,
although such a thing is possible in future.

Joachim Wieland, reviewed by Jeff Davis; also hacked on by me.

Still to be done: fix docs and fix regression failures under auto_explain.

Prevent use of another buggy version of Safe.pm.
Only register the exit handler if we have  successfully created an interpreter.
Change log level of perl warnings from NOTICE to WARNING.

The infrastructure is there if in future we decide to allow
DBAs to specify extra modules that will be allowed in trusted code.
However, for now the relevant variables are declared as lexicals
rather than as package variables, so that they are not (or should not be)
accessible.

Mostly code from Tim Bunce, reviewed by Alex Hunsaker, with some
tweaks by me.

document the behavior of terse and verbose output options.

honored by YYYY.  Also document Oracle "toggle" FM behavior.

Per report from Guy Rouillier

versions match, per report from Peter.

is invisible in psql, other interfaces, like libpq, make this value
visible.

Boszormenyi Zoltan

existing *.pl conversion script.

Andreas 'ads' Scherbaum

and use this in pq_getbyte_if_available.

It's only a limited implementation which swithes the whole emulation layer
no non-blocking mode, but that's enough as long as non-blocking is only
used during a short period of time, and only one socket is accessed during
this time.

By Zoltán Böszörményi

and move the context information into errcontext instead of errmsg.
This makes them better conform to our guidelines.

Also remove a few errcode declarations that were providing the default
value ERRCODE_INTERNAL_ERROR.

Jan Urbanski

until we can work out portability issues the build farm uncovered.

In passing avoid fsyncing subdirectories twice.

Also adjust documentation of DO.

Patch from David Fetter and subsequent discussion.

Display explain buffers measurements in memory units rather than blocks. Also show "Total Buffer Usage" to hint that these are totals not averages per loop