specified in just one place and adhered to exactly, rather than just more
or less.  A side effect is to increase PGSTAT_ACTIVITY_SIZE (maximum
reported query length) from 256 to nearly 1000.

begin the shutdown checkpoint; there isn't anything left for them to do,
so we may as well ensure that they shut down sooner rather than later.
Per discussion.

place of time_t, as per prior discussion.  The behavior does not change
on machines without a 64-bit-int type, but on machines with one, which
is most, we are rid of the bizarre boundary behavior at the edges of
the 32-bit-time_t range (1901 and 2038).  The system will now treat
times over the full supported timestamp range as being in your local
time zone.  It may seem a little bizarre to consider that times in
4000 BC are PST or EST, but this is surely at least as reasonable as
propagating Gregorian calendar rules back that far.

I did not modify the format of the zic timezone database files, which
means that for the moment the system will not know about daylight-savings
periods outside the range 1901-2038.  Given the way the files are set up,
it's not a simple decision like 'widen to 64 bits'; we have to actually
think about the range of years that need to be supported.  We should
probably inquire what the plans of the upstream zic people are before
making any decisions of our own.

than being random pieces of other files.  Give bgwriter responsibility
for all checkpoint activity (other than a post-recovery checkpoint);
so this child process absorbs the functionality of the former transient
checkpoint and shutdown subprocesses.  While at it, create an actual
include file for postmaster.c, which for some reason never had its own
file before.

about a third, make it work on non-Windows platforms again.  (But perhaps
I broke the WIN32 code, since I have no way to test that.)  Fold all the
paths that fork postmaster child processes to go through the single
routine SubPostmasterMain, which takes care of resurrecting the state that
would normally be inherited from the postmaster (including GUC variables).
Clean up some places where there's no particularly good reason for the
EXEC and non-EXEC cases to work differently.  Take care of one or two
FIXMEs that remained in the code.

TZ stuff (and possibly others) to work in the pgstat backends.

Magnus Hagander

backend startup.

recovering from an unexpected backend termination.

The remaining patches are to allow whitespace in db/install directory
names.

Claudio Natoli

* removed a few redundant defines
* get_user_name safe under win32
* rationalized pipe read EOF for win32 (UPDATED PATCH USED)
* changed all backend instances of sleep() to pg_usleep

    - except for the SLEEP_ON_ASSERT in assert.c, as it would exceed a
32-bit long [Note to patcher: If a SLEEP_ON_ASSERT of 2000 seconds is
acceptable, please replace with pg_usleep(2000000000L)]

I added a comment to that part of the code:

    /*
     *  It would be nice to use pg_usleep() here, but only does 2000 sec
     *  or 33 minutes, which seems too short.
     */
    sleep(1000000);

Claudio Natoli

It works on the principle of turning sockets into non-blocking, and then
emulate blocking behaviour on top of that, while allowing signals to
run. Signals are now implemented using an event instead of APCs, thus
getting rid of the issue of APCs not being compatible with "old style"
sockets functions.

It also moves the win32 specific code away from pqsignal.h/c into
port/win32, and also removes the "thread style workaround" of the APC
issue previously in place.

In order to make things work, a few things are also changed in pgstat.c:

1) There is now a separate pipe to the collector and the bufferer. This
is required because the pipe will otherwise only be signalled in one of
the processes when the postmaster goes down. The MS winsock code for
select() must have some kind of workaround for this behaviour, but I
have found no stable way of doing that. You really are not supposed to
use the same socket from more than one process (unless you use
WSADuplicateSocket(), in which case the docs specifically say that only
one will be flagged).

2) The check for "postmaster death" is moved into a separate select()
call after the main loop. The previous behaviour select():ed on the
postmaster pipe, while later explicitly saying "we do NOT check for
postmaster exit inside the loop".
The issue was that the code relies on the same select() call seeing both
the postmaster pipe *and* the pgstat pipe go away. This does not always
happen, and it appears that useing WSAEventSelect() makes it even more
common that it does not.
Since it's only called when the process exits, I don't think using a
separate select() call will have any significant impact on how the stats
collector works.

Magnus Hagander

be built under VC++. Moves a pgstat win32 #def to port.h

Claudio Natoli

ensure that it actually passes data.  This catches cases such as a kernel
packet filter rule that makes the socket useless.

Andrew Dunstan

implementation.

Claudio Natoli

initialization of stats process under EXEC_BACKEND.

[A cleaner, rationalized approach to stat/backend/SSDataBase child
processes under EXEC_BACKEND is on my TODO list. However this patch
takes care of immediate concerns (ie. stats test now passes under
win32)]

Claudio Natoli

whereToSendOutput instead because they are really inquiring about
the correct client communication protocol.  Update some comments.
This is pointing towards supporting regular FE/BE client protocol
in a standalone backend, per discussion a month or so back.

PostmasterPid variable, which gets set (early) in PostmasterMain
getppid would not be the postmaster?

[fork/exec] Implements processCancelRequest by keeping an array of

pid/cancel_key structs in shared mem

[fork/exec] Moves AttachSharedMemoryAndSemaphores call for backends into
SubPostmasterMain

[win32] Implements reaper/waitpid by keeping an arrays of children
pids,handles in postmaster local mem
      - this item is largely untested, for reasons which should be
obvious, but appears sound

[win32/all] Added extern for pgpipe in Win32 case, and changed the second
pipe call (which seems to have been missed earlier) to pgpipe

[win32] #define'd ftruncate to chsize in the Win32 case

[win32] PG_USLEEP for Win32 has a misplaced paren. Fixed.

[win32] DLLIMPORT handling for MingW case


Claudio Natoli

apply.

Alvaro Herrera

fork/exec portion of the port), and fixes a handful of whitespace issues

Claudio Natoli

Claudio Natoli

BackendFork/SSDataBase/pgstat) startup, to allow fork/exec calls to
closely mimic (the soon to be provided) Win32 CreateProcess equivalent
calls.

Claudio Natoli

fork/exec'd, in the same mode as the previous patch for backends.

Claudio Natoli

Claudio Natoli

$Header: -> $PostgreSQL Changes ...

to try additional addresses returned from getaddrinfo() if the first one
fails at the bind() or connect() steps.  Per yesterday's discussion.

they do not prevent the postmaster from deleting the shmem segment during
a post-backend-crash restart cycle.  Per recent discussion.

terms, add some clarifications, fix some untranslatable attempts at dynamic
message building.

by recent IPv6 changes, and since it's redundant with a kernel-level check
anyway, it seems not worth trying to fix it.  Per recent discussions.

search loop in pgstat_initstats.  Per report from Gavin Sherry.

was modified for IPv6.  Use a robust definition of struct sockaddr_storage,
do a proper configure test to see if ss_len exists, don't assume that
getnameinfo() will handle AF_UNIX sockets, don't trust getaddrinfo to
return the protocol we ask for, etc.  This incorporates several outstanding
patches from Kurt Roeckx, but I'm to blame for anything that doesn't
work ...

Along the way, fix some logic problems in pgstat_initstats, notably the
bogus assumption that malloc returns zeroed memory.

Kurt Roeckx
Andrew Dunstan