this case is worth a special code path, but a special code path that gets
the boundary condition wrong is definitely no good. Per bug #4821 from
Andrew Gierth.
In passing, clean up some minor code formatting issues (excess parentheses
and blank lines in odd places).
Back-patch to 8.3, where the bug was introduced.
redirecting libxml's allocations into a Postgres context. Instead, just let
it use malloc directly, and add PG_TRY blocks as needed to be sure we release
libxml data structures in error recovery code paths. This is ugly but seems
much more likely to play nicely with third-party uses of libxml, as seen in
recent trouble reports about using Perl XML facilities in pl/perl and bug
#4774 about contrib/xml2.
I left the code for allocation redirection in place, but it's only
built/used if you #define USE_LIBXMLCONTEXT. This is because I found it
useful to corral libxml's allocations in a palloc context when hunting
for libxml memory leaks, and we're surely going to have more of those
in the future with this type of approach. But we don't want it turned on
in a normal build because it breaks exactly what we need to fix.
I have not re-indented most of the code sections that are now wrapped
by PG_TRY(); that's for ease of review. pg_indent will fix it.
This is a pre-existing bug in 8.3, but I don't dare back-patch this change
until it's gotten a reasonable amount of field testing.
xml_parse, all arising from the same sloppy usage of parse_xml_decl.
The original coding had that function returning its output string
parameters in the libxml context, which is long-lived, and all but one
of its callers neglected to free the strings afterwards. The easiest
and most bulletproof fix is to return the strings in the local palloc
context instead, since that's short-lived. This was only costing a
dozen or two bytes per function call, but that adds up fast if the
function is called repeatedly ...
Noted while poking at the more general problem of what to do with our
libxml memory allocation hooks. Back-patch to 8.3, which has the
identical coding.
a backend has done exit(0) or exit(1) without having disengaged itself
from shared memory. We are at risk for this whenever third-party code is
loaded into a backend, since such code might not know it's supposed to go
through proc_exit() instead. Also, it is reported that under Windows
there are ways to externally kill a process that cause the status code
returned to the postmaster to be indistinguishable from a voluntary exit
(thank you, Microsoft). If this does happen then the system is probably
hosed --- for instance, the dead session might still be holding locks.
So the best recovery method is to treat this like a backend crash.
The dead man switch is armed for a particular child process when it
acquires a regular PGPROC, and disarmed when the PGPROC is released;
these should be the first and last touches of shared memory resources
in a backend, or close enough anyway. This choice means there is no
coverage for auxiliary processes, but I doubt we need that, since they
shouldn't be executing any user-provided code anyway.
This patch also improves the management of the EXEC_BACKEND
ShmemBackendArray array a bit, by reducing search costs.
Although this problem is of long standing, the lack of field complaints
seems to mean it's not critical enough to risk back-patching; at least
not till we get some more testing of this mechanism.
error message if the installation directory layout is messed up (or at least,
something more useful than the behavior exhibited in bug #4787). During
postmaster startup, check that get_pkglib_path resolves as a readable
directory; and if ParseTzFile() fails to open the expected timezone
abbreviation file, check the possibility that the directory is missing rather
than just the specified file. In case of either failure, issue a hint
suggesting that the installation is broken. These two checks cover the lib/
and share/ trees of a full installation, which should take care of most
scenarios where a sysadmin decides to get cute.
part that rounds up to exactly 1.0 second. The previous coding rejected input
like "00:12:57.9999999999999999999999999999", with the exact number of nines
needed to cause failure varying depending on float-timestamp option and
possibly on platform. Obviously this should round up to the next integral
second, if we don't have enough precision to distinguish the value from that.
Per bug #4789 from Robert Kruus.
In passing, fix a missed check for fractional seconds in one copy of the
"is it greater than 24:00:00" code.
Broken all the way back, so patch all the way back.
any negative or positive number, not just -1 or 1. Fix comment on
varstr_cmp and citext test case accordingly.
As pointed out by Zdenek Kotala, and buildfarm member gothic moth.
documentation warnings against setting it nonzero unless active use of
prepared transactions is intended and a suitable transaction manager has been
installed. This should help to prevent the type of scenario we've seen
several times now where a prepared transaction is forgotten and eventually
causes severe maintenance problems (or even anti-wraparound shutdown).
The only real reason we had the default be nonzero in the first place was to
support regression testing of the feature. To still be able to do that,
tweak pg_regress to force a nonzero value during "make check". Since we
cannot force a nonzero value in "make installcheck", add a variant regression
test "expected" file that shows the results that will be obtained when
max_prepared_transactions is zero.
Also, extend the HINT messages for transaction wraparound warnings to mention
the possibility that old prepared transactions are causing the problem.
All per today's discussion.
Stefan Kaltenbrunner. The most reasonable behavior (at least for the near
term) seems to be to ignore the PlaceHolderVar and examine its argument
instead. In support of this, change the API of pull_var_clause() to allow
callers to request recursion into PlaceHolderVars. Currently
estimate_num_groups() is the only customer for that behavior, but where
there's one there may be others.
how this ought to behave for multi-dimensional arrays. Per discussion,
not having it at all seems better than having it with what might prove
to be the wrong behavior. We can always add it later when we have consensus
on the correct behavior.
already did that on Windows, but it's needed on other platforms too when
LC_CTYPE=C. With other locales, we enforce (or trust) that the codeset of
the locale matches the server encoding so we don't need to bind it
explicitly. It should do no harm in that case either, but I don't have
full faith in the PG encoding -> OS codeset mapping table yet. Per recent
discussion on pgsql-hackers.
alias for array_length(v,1). The efficiency gain here is doubtless
negligible --- what I'm interested in is making sure that if we have
second thoughts about the definition, we will not have to force a
post-beta initdb to change the implementation.
are individually labeled, rather than just grouped under an "InitPlan"
or "SubPlan" heading. This in turn makes it possible for decompilation of
a subplan reference to usefully identify which subplan it's referencing.
I also made InitPlans identify which parameter symbol(s) they compute,
so that references to those parameters elsewhere in the plan tree can
be connected to the initplan that will be executed. Per a gripe from
Robert Haas about EXPLAIN output of a WITH query being inadequate,
plus some longstanding pet peeves of my own.
interval_eq() considers equal. I'm not sure how that fundamental requirement
escaped us through multiple revisions of this hash function, but there it is;
it's been wrong since interval_hash was first written for PG 7.1.
Per bug #4748 from Roman Kononov.
Backpatch to all supported releases.
This patch changes the contents of hash indexes for interval columns. That's
no particular problem for PG 8.4, since we've broken on-disk compatibility
of hash indexes already; but it will require a migration warning note in
the next minor releases of all existing branches: "if you have any hash
indexes on columns of type interval, REINDEX them after updating".
conversion functions. This allows transaction rollback to revert to a
previous client_encoding setting without doing fresh catalog lookups.
I believe that this explains and fixes the recent report of "failed to commit
client_encoding" failures.
This bug is present in 8.3.x, but it doesn't seem prudent to back-patch
the fix, at least not till it's had some time for field testing in HEAD.
In passing, remove SetDefaultClientEncoding(), which was used nowhere.
we failed to assign, even in "can't happen" cases. Motivated by wondering
what's going on in a recent trouble report where "failed to commit" did
happen.
temp relations; this is no more expensive than before, now that we have
pg_class.relistemp. Insert tests into bufmgr.c to prevent attempting
to fetch pages from nonlocal temp relations. This provides a low-level
defense against bugs-of-omission allowing temp pages to be loaded into shared
buffers, as in the contrib/pgstattuple problem reported by Stuart Bishop.
While at it, tweak a bunch of places to use new relcache tests (instead of
expensive probes into pg_namespace) to detect local or nonlocal temp tables.
relations (including a temp table's indexes and toast table/index), and
false for normal relations. For ease of checking, this commit just adds
the column and fills it correctly --- revising the relation access machinery
to use it will come separately.
mode while callers hold pointers to in-memory tuples. I reported this for
the case of nodeWindowAgg's primary scan tuple, but inspection of the code
shows that all of the calls in nodeWindowAgg and nodeCtescan are at risk.
For the moment, fix it with a rather brute-force approach of copying
whenever one of the at-risk callers requests a tuple. Later we might
think of some sort of reference-count approach to reduce tuple copying.
method to pass extra data to the consistent() and comparePartial() methods.
This is the core infrastructure needed to support the soon-to-appear
contrib/btree_gin module. The APIs are still upward compatible with the
definitions used in 8.3 and before, although *not* with the previous 8.4devel
function definitions.
catversion bump for changes in pg_proc entries (although these are just
cosmetic, since GIN doesn't actually look at the function signature before
calling it...)
Teodor Sigaev and Oleg Bartunov
probes --- the BUFFER_READ_DONE probe provides the same information and more
besides. Expand the LOCK_WAIT_START/DONE probe arguments so that there's
actually some chance of telling what is being waited for. Update and
clean up the documentation.
DTrace probes, so that ordinary reads can be distinguished from relation
extension operations. Move buffer_read_start probe to before the
smgrnblocks() call that's needed in the isExtend case, since really that step
should be charged as part of the time needed for the extension operation.
(This makes it slightly harder to match the read_start with the associated
read_done, since now you can't match them on blockNumber, but it should still
be possible since isExtend operations on the same relation can never be
interleaved.) Per recent discussion.
In passing, add the page identity (forkNum/blockNum) to the parameters of the
buffer_flush_start/buffer_flush_done probes, which were unaccountably lacking
the info.
noise words for the last twelve years, for compatibility with Berkeley-era
output formatting of the special INVALID values for those datatypes.
Considering that the datatypes themselves have been deprecated for awhile,
this is taking backwards compatibility a little far. Per gripe from Josh
Berkus.
