indexes when the index column type (the opclass opckeytype) is different from
the expression's datatype. When coded, this limitation wasn't worth worrying
about because we had no intelligence to speak of in stats collection for the
datatypes used by such opclasses. However, now that there's non-toy
estimation capability for tsvector queries, it amounts to a bug that ANALYZE
fails to do this.
The fix changes struct VacAttrStats, and therefore constitutes an API break
for custom typanalyze functions. Therefore we can't back-patch it into
released branches, but it was agreed that 9.0 isn't yet frozen hard enough
to make such a change unacceptable. Ergo, back-patch to 9.0 but no further.
The API break had better be mentioned in 9.0 release notes.
Although the key-combining code claimed to work correctly if its input
contained both lossy and exact pointers for a single page in a single TID
stream, in fact this did not work, and could not work without pretty
fundamental redesign. Modify keyGetItem so that it will not return such a
stream, by handling lossy-pointer cases a bit more explicitly than we did
before.
Per followup investigation of a gripe from Artur Dabrowski.
An example of a query that failed given his data set is
select count(*) from search_tab where
(to_tsvector('german', keywords ) @@ to_tsquery('german', 'ee:* | dd:*')) and
(to_tsvector('german', keywords ) @@ to_tsquery('german', 'aa:*'));
Back-patch to 8.4 where the lossy pointer code was introduced.
struct representing a tree entry, rather than being a separately allocated
piece of storage. This API is at least as clean as the old one (if not
more so --- there were some bizarre choices in there) and it permits a
very substantial memory savings, on the order of 2X in ginbulk.c's usage.
Also, fix minor memory leaks in code called by ginEntryInsert, in
particular in ginInsertValue and entryFillRoot, as well as ginEntryInsert
itself. These leaks resulted in the GIN index build context continuing
to bloat even after we'd filled it to maintenance_work_mem and started
to dump data out to the index.
In combination these fixes restore the GIN index build code to honoring
the maintenance_work_mem limit about as well as it did in 8.4. Speed
seems on par with 8.4 too, maybe even a bit faster, for a non-pathological
case in which HEAD was formerly slower.
Back-patch to 9.0 so we don't have a performance regression from 8.4.
routines to make them behave better in the presence of "lossy" index pointers.
The previous coding was outright incorrect for some cases, as recently
reported by Artur Dabrowski: scanGetItem would fail to return index entries in
cases where one index key had multiple exact pointers on the same page as
another key had a lossy pointer. Also, keyGetItem was extremely inefficient
for cases where a single index key generates multiple "entry" streams, such as
an @@ operator with a multiple-clause tsquery. The presence of a lossy page
pointer in any one stream defeated its ability to use the opclass
consistentFn, resulting in probing many heap pages that didn't really need to
be visited. In Artur's example case, a query like
WHERE tsvector @@ to_tsquery('a & b')
was about 50X slower than the theoretically equivalent
WHERE tsvector @@ to_tsquery('a') AND tsvector @@ to_tsquery('b')
The way that I chose to fix this was to have GIN call the consistentFn
twice with both TRUE and FALSE values for the in-doubt entry stream,
returning a hit if either call produces TRUE, but not if they both return
FALSE. The code handles this for the case of a single in-doubt entry stream,
but punts (falling back to the stupid behavior) if there's more than one lossy
reference to the same page. The idea could be scaled up to deal with multiple
lossy references, but I think that would probably be wasted complexity. At
least to judge by Artur's example, such cases don't occur often enough to be
worth trying to optimize.
Back-patch to 8.4. 8.3 did not have lossy GIN index pointers, so not
subject to these problems.
look through join alias Vars to avoid breaking join queries, and
move the test to someplace where it will catch more possible ways
of calling a function. We still ought to throw away the whole thing
in favor of a data-type-based solution, but that's not feasible in
the back branches.
This needs to be back-patched further than 9.0, but I don't have time
to do so today. Committing now so that the fix gets into 9.0beta4.
related functions. Per today's discussion, we will henceforth assume
that datatype I/O functions are either stable or immutable, never volatile.
(This implies in particular that domain CHECK constraint expressions shouldn't
be volatile, since domain_in executes them.) In turn, functions that execute
the I/O functions of arbitrary datatypes should always be labeled stable.
This affects the labeling of array_to_string, which was unsafely marked
immutable, and record_in, record_out, record_recv, record_send,
domain_in, domain_recv, which were over-conservatively marked volatile.
The array I/O functions were already marked stable, which is correct
per this policy but would have been wrong if we maintained domain_in
as volatile.
Back-patch to 9.0, along with an earlier fix to correctly mark cash_in
and cash_out as stable not immutable (since they depend on lc_monetary).
No catversion bump --- the implications of this are not currently
severe enough to justify a forced initdb.
a pass-by-reference datatype with a nontrivial projection step.
We were using the same memory context for the projection operation as for
the temporary context used by the hashtable routines in execGrouping.c.
However, the hashtable routines feel free to reset their temp context at
any time, which'd lead to destroying input data that was still needed.
Report and diagnosis by Tao Ma.
Back-patch to 8.1, where the problem was introduced by the changes that
allowed us to work with "virtual" tuples instead of materializing intermediate
tuple values everywhere. The earlier code looks quite similar, but it doesn't
suffer the problem because the data gets copied into another context as a
result of having to materialize ExecProject's output tuple.
being used in a PL/pgSQL FOR loop is closed was inadequate, as Tom Lane
pointed out. The bug affects FOR statement variants too, because you can
close an implicitly created cursor too by guessing the "<unnamed portal X>"
name created for it.
To fix that, "pin" the portal to prevent it from being dropped while it's
being used in a PL/pgSQL FOR loop. Backpatch all the way to 7.4 which is
the oldest supported version.
max_standby_streaming_delay, and revise the implementation to avoid assuming
that timestamps found in WAL records can meaningfully be compared to clock
time on the standby server. Instead, the delay limits are compared to the
elapsed time since we last obtained a new WAL segment from archive or since
we were last "caught up" to WAL data arriving via streaming replication.
This avoids problems with clock skew between primary and standby, as well
as other corner cases that the original coding would misbehave in, such
as the primary server having significant idle time between transactions.
Per my complaint some time ago and considerable ensuing discussion.
Do some desultory editing on the hot standby documentation, too.
Backpatch to 8.3, which is as far back as we have opfamilies.
The opclass portion could probably be backpatched to 8.2, when
REASSIGN OWNED was added, but for now I have not done that.
Asko Tiidumaa, with minor adjustments by me.
master. Otherwise a subsequent crash could cause the master to lose WAL that
has already been applied on the slave, resulting in the slave being out of
sync and soon corrupt. Per recent discussion and an example from Robert Haas.
Fujii Masao
description for vacuum_defer_cleanup_age to the correct category.
Sections in postgresql.conf are also sorted in the same order with docs.
Per gripe by Fujii Masao, suggestion by Heikki Linnakangas, and patch by me.
and current server clock time to SR data messages. These are not currently
used on the slave side but seem likely to be useful in future, and it'd be
better not to change the SR protocol after release. Per discussion.
Also do some minor code review and cleanup on walsender.c, and improve the
protocol documentation.
immutable, but that is wrong in general because the cast from the polymorphic
argument to text could be stable or even volatile. Mark them volatile for
safety. In the typical case where the cast isn't volatile, the planner will
deduce the correct expression volatility after inlining the function, so
performance is not lost. The just-committed fix in CREATE INDEX also ensures
this won't break any indexing cases that ought to be allowed.
Per discussion, I'm not bumping catversion for this change, as it doesn't
seem critical enough to force an initdb on beta testers.
During Hot Standby we need to check for buffer pin deadlocks when the
Startup process begins to wait, in case it never wakes up again. We
previously made the deadlock check immediately on the basis it was
cheap, though clearer thinking and prima facie evidence shows that
was too simple. Refactor existing code to make it easy to add in
deferral of deadlock check until deadlock_timeout allowing a good
reduction in deadlock checks since far few buffer pins are held for
that duration. It's worth doing anyway, though major goal is to
prevent further reports of context switching with high numbers of
users on occasional tests.
of requirements and documentation on LogStandbySnapshot(). Fixes
two minor bugs reported by Tom Lane that would lead to an incorrect
snapshot after transaction wraparound. Also fix two other problems
discovered that would give incorrect snapshots in certain cases.
ProcArrayApplyRecoveryInfo() substantially rewritten. Some minor
refactoring of xact_redo_apply() and ExpireTreeKnownAssignedTransactionIds().
confusion with streaming-replication settings. Also, change its default
value to "off", because of concern about executing new and poorly-tested
code during ordinary non-replicating operation. Per discussion.
In passing do some minor editing of related documentation.
archival or hot standby should be WAL-logged, instead of deducing that from
other options like archive_mode. This replaces recovery_connections GUC in
the primary, where it now has no effect, but it's still used in the standby
to enable/disable hot standby.
Remove the WAL-logging of "unlogged operations", like creating an index
without WAL-logging and fsyncing it at the end. Instead, we keep a copy of
the wal_mode setting and the settings that affect how much shared memory a
hot standby server needs to track master transactions (max_connections,
max_prepared_xacts, max_locks_per_xact) in pg_control. Whenever the settings
change, at server restart, write a WAL record noting the new settings and
update pg_control. This allows us to notice the change in those settings in
the standby at the right moment, they used to be included in checkpoint
records, but that meant that a changed value was not reflected in the
standby until the first checkpoint after the change.
Bump PG_CONTROL_VERSION and XLOG_PAGE_MAGIC. Whack XLOG_PAGE_MAGIC back to
the sequence it used to follow, before hot standby and subsequent patches
changed it to 0x9003.
of parameters. Fix bug report by Robert Haas that error message and
hint was incorrect if wrong mode parameters specified on master.
Internal changes only. Proposals for parameter simplification on
master/primary still under way.
vacuum_log_cleanup_info() now generates log records with a valid
latestRemovedXid set in all cases. Also be careful not to zero the
value when we do a round of vacuuming part-way through lazy_scan_heap().
Incidentally, this reduces frequency of conflicts in Hot Standby.
database to connect to. This is necessary for the walsender code to work
properly (it was previously using an untenable assumption that template1 would
always be available to connect to). This also gets rid of a small security
shortcoming that was introduced in the original patch to eliminate the flat
authentication files: before, you could find out whether or not the requested
database existed even if you couldn't pass the authentication checks.
The changes needed to support this are mainly just to treat pg_authid and
pg_auth_members as nailed relations, so that we can read them without having
to be able to locate real pg_class entries for them. This mechanism was
already debugged for pg_database, but we hadn't recognized the value of
applying it to those catalogs too.
Since the current code doesn't have support for accessing toast tables before
we've brought up all of the relcache, remove pg_authid's toast table to ensure
that no one can store an out-of-line toasted value of rolpassword. The case
seems quite unlikely to occur in practice, and was effectively unsupported
anyway in the old "flatfiles" implementation.
Update genbki.pl to actually implement the same rules as bootstrap.c does for
not-nullability of catalog columns. The previous coding was a bit cheesy but
worked all right for the previous set of bootstrap catalogs. It does not work
for pg_authid, where rolvaliduntil needs to be nullable.
Initdb forced due to minor catalog changes (mainly the toast table removal).
Also, make the name of the GUC and the name of the backing variable match.
Alnong the way, clean up a couple of slight typographical errors in the
related docs.
