SI messages now include the relevant database OID, so that operations
in one database do not cause useless cache flushes in backends attached
to other databases. Declare SI messages properly using a union, to
eliminate the former assumption that Oid is the same size as int or Index.
Rewrite the nearly-unreadable code in inval.c, and document it better.
Arrange for catcache flushes at end of command/transaction to happen before
relcache flushes do --- this avoids loading a new tuple into the catcache
while setting up new relcache entry, only to have it be flushed again
immediately.
Cygwin with the possible exception of mSQL-interface. Since I don't
have mSQL installed, I skipped this tool.
Except for dealing with a missing getopt.h (oid2name) and HUGE (seg),
the bulk of the patch uses the standard PostgreSQL approach to deal with
Windows DLL issues.
I tested the build aspect of this patch under Cygwin and Linux without
any ill affects. Note that I did not actually attempt to test the code
for functionality.
The procedure to apply the patch is as follows:
$ # save the attachment as /tmp/contrib.patch
$ # change directory to the top of the PostgreSQL source tree
$ patch -p0 </tmp/contrib.patch
Jason
detected sooner in backend startup, and is treated as an expected error
(it gives 'Sorry, too many clients already' now). This allows us not
to have to enforce the MaxBackends limit exactly in the postmaster.
Also, remove ProcRemove() and fold its functionality into ProcKill().
There's no good reason for a backend not to be responsible for removing
its PROC entry, and there are lots of good reasons for the postmaster
not to be touching shared-memory data structures.
directory (which can be made a symlink to put temp files on another disk).
Add code to delete leftover temp files during postmaster startup.
Bruce, with some kibitzing from Tom.
appropriate pin-count manipulation, and instead use ReleaseAndReadBuffer.
Make use of the fact that the passed-in buffer (if there is one) must
be pinned to avoid grabbing the bufmgr spinlock when we are able to
return this same buffer. Eliminate unnecessary 'previous tuple' and
'next tuple' fields of HeapScanDesc and IndexScanDesc, thereby removing
a whole lot of bookkeeping from heap_getnext() and related routines.
Python) to support shared extension modules, I have learned that Guido
prefers the style of the attached patch to solve the above problem.
I feel that this solution is particularly appropriate in this case
because the following:
PglargeType
PgType
PgQueryType
are already being handled in the way that I am proposing for PgSourceType.
Jason Tishler
it does not support 64bit integers. AFAIK that's the default data type for
OIDs, so I am not surprised that this does not work. Use gcc instead.
BTW., 7.1 does not compile as is with gcc either, I believed the
required patches made it into the 7.1.1 release but obviously I missed
the deadline.
Since the ports mailing list does not seem to be archived I have attached
a copy of the patch (for 7.1 and 7.1.1).
I've just performed a build of a Watcom compiled version and found a couple
of bugs in the watcom specific part of that patch. Please use the attached
version instead.
Tegge, Bernd
when we need to move to a new page; as long as we can insert the new
tuple on the same page as before, we only need LockBuffer and not the
expensive stuff. Also, twiddle bufmgr interfaces to avoid redundant
lseeks in RelationGetBufferForTuple and BufferAlloc. Successive inserts
now require one lseek per page added, rather than one per tuple with
several additional ones at each page boundary as happened before.
Lock contention when multiple backends are inserting in same table
is also greatly reduced.
not being consulted anywhere, so remove it and remove the _mdnblocks()
calls that were used to set it. Change smgrextend interface to pass in
the target block number (ie, current file length) --- the caller always
knows this already, having already done smgrnblocks(), so it's silly to
do it over again inside mdextend. Net result: extension of a file now
takes one lseek(SEEK_END) and a write(), not three lseeks and a write.
as six bytes not eight. This fixes a regression test failure but more
importantly avoids wasting four bytes of pad space in every tuple header.
Also add some commentary about what's going on.
* Store two past checkpoint locations, not just one, in pg_control.
On startup, we fall back to the older checkpoint if the newer one
is unreadable. Also, a physical copy of the newest checkpoint record
is kept in pg_control for possible use in disaster recovery (ie,
complete loss of pg_xlog). Also add a version number for pg_control
itself. Remove archdir from pg_control; it ought to be a GUC
parameter, not a special case (not that it's implemented yet anyway).
* Suppress successive checkpoint records when nothing has been entered
in the WAL log since the last one. This is not so much to avoid I/O
as to make it actually useful to keep track of the last two
checkpoints. If the things are right next to each other then there's
not a lot of redundancy gained...
* Change CRC scheme to a true 64-bit CRC, not a pair of 32-bit CRCs
on alternate bytes. Polynomial borrowed from ECMA DLT1 standard.
* Fix XLOG record length handling so that it will work at BLCKSZ = 32k.
* Change XID allocation to work more like OID allocation. (This is of
dubious necessity, but I think it's a good idea anyway.)
* Fix a number of minor bugs, such as off-by-one logic for XLOG file
wraparound at the 4 gig mark.
* Add documentation and clean up some coding infelicities; move file
format declarations out to include files where planned contrib
utilities can get at them.
* Checkpoint will now occur every CHECKPOINT_SEGMENTS log segments or
every CHECKPOINT_TIMEOUT seconds, whichever comes first. It is also
possible to force a checkpoint by sending SIGUSR1 to the postmaster
(undocumented feature...)
* Defend against kill -9 postmaster by storing shmem block's key and ID
in postmaster.pid lockfile, and checking at startup to ensure that no
processes are still connected to old shmem block (if it still exists).
* Switch backends to accept SIGQUIT rather than SIGUSR1 for emergency
stop, for symmetry with postmaster and xlog utilities. Clean up signal
handling in bootstrap.c so that xlog utilities launched by postmaster
will react to signals better.
* Standalone bootstrap now grabs lockfile in target directory, as added
insurance against running it in parallel with live postmaster.
only if at least N other backends currently have open transactions. This
is not a great deal of intelligence about whether a delay might be
profitable ... but it beats no intelligence at all. Note that the default
COMMIT_DELAY is still zero --- this new code does nothing unless that
setting is changed.
Also, mark ENABLEFSYNC as a system-wide setting. It's no longer safe to
allow that to be set per-backend, since we may be relying on some other
backend's fsync to have synced the WAL log.
> Is there one LOCKMETHODCTL for every backend? I thought there was only
> one of them.
>>
>> You're right, that line is erroneous; it should read
>>
>> size += MAX_LOCK_METHODS * MAXALIGN(sizeof(LOCKMETHODCTL));
>>
>> Not a significant error but it should be changed for clarity ...
waste of cycles on single-CPU machines, and of dubious utility on multi-CPU
machines too.
Tweak s_lock_stuck so that caller can specify timeout interval, and
increase interval before declaring stuck spinlock for buffer locks and XLOG
locks.
On systems that have fdatasync(), use that rather than fsync() to sync WAL
log writes. Ensure that WAL file is entirely allocated during XLogFileInit.
are now separate files "postgres.h" and "postgres_fe.h", which are meant
to be the primary include files for backend .c files and frontend .c files
respectively. By default, only include files meant for frontend use are
installed into the installation include directory. There is a new make
target 'make install-all-headers' that adds the whole content of the
src/include tree to the installed fileset, for use by people who want to
develop server-side code without keeping the complete source tree on hand.
Cleaned up a whole lot of crufty and inconsistent header inclusions.
rewrite of deadlock checking. Lock holder objects are now reachable from
the associated LOCK as well as from the owning PROC. This makes it
practical to find all the processes holding a lock, as well as all those
waiting on the lock. Also, clean up some of the grottier aspects of the
SHMQueue API, and cause the waitProcs list to be stored in the intuitive
direction instead of the nonintuitive one. (Bet you didn't know that
the code followed the 'prev' link to get to the next waiting process,
instead of the 'next' link. It doesn't do that anymore.)
whitespace is unimportant in assembly code. Also, move VAX definition
of typedef slock_t to port header files to be like all the other ports.
Note that netbsd.h and openbsd.h are now identical, and I rather think
that freebsd.h is broken in the places where it doesn't agree --- but
I'll leave it to the freebsders to look at that.
are treated more like 'cancel' interrupts: the signal handler sets a
flag that is examined at well-defined spots, rather than trying to cope
with an interrupt that might happen anywhere. See pghackers discussion
of 1/12/01.
for Alpha gcc case. For Alpha non-gcc case, replace use of
__INTERLOCKED_TESTBITSS_QUAD builtin with __LOCK_LONG_RETRY and
__UNLOCK_LONG. The former does not execute an MB instruction and
therefore was guaranteed not to work on multiprocessor machines.
The LOCK_LONG builtins produce code that is the same in all essential
details as the gcc assembler code.
assume that TAS() will always succeed the first time, even if the lock
is known to be free. Also, make sure that code will eventually time out
and report a stuck spinlock, rather than looping forever. Small cleanups
in s_lock.h, too.
level" locks. A session lock is not released at transaction commit (but it
is released on transaction abort, to ensure recovery after an elog(ERROR)).
In VACUUM, use a session lock to protect the master table while vacuuming a
TOAST table, so that the TOAST table can be done in an independent
transaction.
I also took this opportunity to do some cleanup and renaming in the lock
code. The previously noted bug in ProcLockWakeup, that it couldn't wake up
any waiters beyond the first non-wakeable waiter, is now fixed. Also found
a previously unknown bug of the same kind (failure to scan all members of
a lock queue in some cases) in DeadLockCheck. This might have led to failure
to detect a deadlock condition, resulting in indefinite waits, but it's
difficult to characterize the conditions required to trigger a failure.
to ensure that we have released buffer refcounts and so forth, rather than
putting ad-hoc operations before (some of the calls to) proc_exit. Add
commentary to discourage future hackers from repeating that mistake.
included by everything that includes bufmgr.h --- it's supposed to be
internals, after all, not part of the API! This fixes the conflict
against FreeBSD headers reported by Rosenman, by making it unnecessary
for s_lock.h to be included by plperl.c.
IPC key assignment will now work correctly even when multiple postmasters
are using same logical port number (which is possible given -k switch).
There is only one shared-mem segment per postmaster now, not 3.
Rip out broken code for non-TAS case in bufmgr and xlog, substitute a
complete S_LOCK emulation using semaphores in spin.c. TAS and non-TAS
logic is now exactly the same.
When deadlock is detected, "Deadlock detected" is now the elog(ERROR)
message, rather than a NOTICE that comes out before an unhelpful ERROR.
that search loops only have to scan that far and not through all maxBackends
entries. This eliminates a performance penalty for setting maxBackends
much higher than the average number of active backends. Also, eliminate
no-longer-used 'backend tag' concept. Remove setting of environment
variables at backend start (except for CYR_RECODE), since none of them
are being examined by the backend any longer.
(WAL logging for this is not done yet, however.) Clean up a number of really
crufty things that are no longer needed now that DROP behaves nicely. Make
temp table mapper do the right things when drop or rename affecting a temp
table is rolled back. Also, remove "relation modified while in use" error
check, in favor of locking tables at first reference and holding that lock
throughout the statement.
as full as possible, seems better to use a tuple size around BLCKSZ/4
so that less space is wasted when a LO tuple is updated. Also, this
lets us use a logical page size that's an exact power of two, avoiding
partial-page writes when client is sending us stuff in power-of-2
buffer chunks.
kibitzing from Tom Lane. Large objects are now all stored in a single
system relation "pg_largeobject" --- no more xinv or xinx files, no more
relkind 'l'. This should offer substantial performance improvement for
large numbers of LOs, since there won't be directory bloat anymore.
It'll also fix problems like running out of locktable space when you
access thousands of LOs in one transaction.
Also clean up cruft in read/write routines. LOs with "holes" in them
(never-written byte ranges) now work just like Unix files with holes do:
a hole reads as zeroes but doesn't occupy storage space.
INITDB forced!
from bufmgr - it would be nice to have separate hash in smgr
for node <--> fd mappings, but for the moment it's easy to
add new hash to relcache.
Fixed small bug in xlog.c:ReadRecord.
* Makefile: Add more standard targets. Improve shell redirection in GNU
make detection.
* src/backend/access/transam/rmgr.c: Fix incorrect(?) C.
* src/backend/libpq/pqcomm.c (StreamConnection): Work around accept() bug.
* src/include/port/unixware.h: ...with help from here.
* src/backend/nodes/print.c (plannode_type): Remove some "break"s after
"return"s.
* src/backend/tcop/dest.c (DestToFunction): ditto.
* src/backend/nodes/readfuncs.c: Add proper prototypes.
* src/backend/utils/adt/numutils.c (pg_atoi): Cope specially with strtol()
setting EINVAL. This saves us from creating an extra set of regression test
output for the affected systems.
* src/include/storage/s_lock.h (tas): Correct prototype.
* src/interfaces/libpq/fe-connect.c (parseServiceInfo): Don't use variable
as dimension in array definition.
* src/makefiles/Makefile.unixware: Add support for GCC.
* src/template/unixware: same here
* src/test/regress/expected/abstime-solaris-1947.out: Adjust whitespace.
* src/test/regress/expected/horology-solaris-1947.out: Part of this file
was evidently missing.
* src/test/regress/pg_regress.sh: Fix shell. mkdir -p returns non-zero if
the directory exists.
* src/test/regress/resultmap: Add entries for Unixware.
> Regression tests opr_sanity and sanity_check are now failing.
Um, Bruce, I've said several times that I didn't think Perchine's large
object changes should be applied until someone had actually reviewed
them.
I tested it restoring my database with > 100000 BLOBS, and dumping it out.
But unfortunatly I can not restore it back due to problems in pg_dump.
--
Sincerely Yours,
Denis Perchine
> > For a while I though it might be because we are using an alpha TAS in
> > the spinlock rather than the old semaphore. I replaced our spinlock
> > with the standard one and it made no difference. We have been running
> > with our spinlock implementation for nearly 2 months on a production
> > database now without a hitch, so I think it is ok. Did I ever submit
> > any patches for the Alpha spinlock?
>
> Not that I recall. We did get some advice from some Alpha gurus at DEC
> who seemed to think the existing TAS code is OK. What was it that you
> felt needed to be improved?
The current code uses semaphores, which has the advantage that it works
well even on multi-processor machines, but the disadvantage that it is not
the fastest way possible. Writing a spinlock on Alpha for SMP machines is
very difficult, as you need to deal with memory barriers. A real mess. But
then one of the people at Compaq pointed out to us that there is a
ready-made routine on Alpha. We implemented it with the two patches below.
I ran tests with lots of parallel back-ends and got around a 10% speed
increase. I include the two patches. Perhaps some of the other people
running Tru64 can have a look at these as well.
Cheers,
Adriaan Joubert
> this is patch v 0.4 to support transactions with BLOBs.
> All BLOBs are in one table. You need to make initdb.
>
> --
> Sincerely Yours,
> Denis Perchine
after that dynamic loading isn't working and shared memory handling is
broken.
Attached with this message, there is a Zip file which contain :
* beos.diff = patch file generated with difforig
* beos = folder with beos support files which need to be moved in /
src/backend/port
* expected = foler with three file for message and precision
difference in regression test
* regression.diff = rule problem (need to kill the backend manualy)
* dynloader = dynloader files (they are also in the pacth files,
but there is so much modification that I have join full files)
Everything works except a problem in 'rules' Is there some problems
with rules in the current tree ? It used to works with last week tree.
Cyril VELTER
working on the VERY latest version of BeOS. I'm sure there will be
alot of comments, but then if there weren't I'd be disappointed!
Thanks for your continuing efforts to get this into your tree.
Haven't bothered with the new files as they haven't changed.
BTW Peter, the compiler is "broken" about the bool define and so on.
I'm filing a bug report to try and get it addressed. Hopefully then we
can tidy up the code a bit.
I await the replies with interest :)
David Reid
problems with some bits of it, but when all the patches are in it'll build
and we can fix it from there :) I've got a version that builds and runs and
that is the basis for these patches.
The first file has the new additional files that are required,
template/beos
backend/port/dynloader/beos.c
backend/port/dynloader/beos.h
include/port/beos.h
makefiles/Makefile.beos
The second is a tarball of diffs against a few files. I've added sys/ipc.h
to configure and config.h via configure.in and config.h.in and then started
adding the check as this file isn't needed on BeOS and having loads of
#ifdef BEOS isn't as obvious as #ifdef HAVE_SYS_IPC_H and isn't as
autconf'ish :)
Files touched are
include/c.h
configure.in
include/config.h.in
include/storage/ipc.h
include/utils/int8.h
Let me know how these go. I'll await a response before submitting any more.
Any problems just get in touch.
David Reid
as MaxHeapAttributeNumber. Increase MaxAttrSize to something more
reasonable (given what it's used for, namely checking char(n) declarations,
I didn't make it the full 1G that it could theoretically be --- 10Mb
seemed a more reasonable number). Improve calculation of MaxTupleSize.
duplicate keys by letting search go to the left rather than right when an
equal key is seen at an upper tree level. Fix poor choice of page split
point (leading to insertion failures) that was forced by chaining logic.
Don't store leftmost key in non-leaf pages, since it's not necessary.
Don't create root page until something is first stored in the index, so an
unused index is now 8K not 16K. (Doesn't seem to be as easy to get rid of
the metadata page, unfortunately.) Massive cleanup of unreadable code,
fix poor, obsolete, and just plain wrong documentation and comments.
See src/backend/access/nbtree/README for the gory details.
There's now only one transition value and transition function.
NULL handling in aggregates is a lot cleaner. Also, use Numeric
accumulators instead of integer accumulators for sum/avg on integer
datatypes --- this avoids overflow at the cost of being a little slower.
Implement VARIANCE() and STDDEV() aggregates in the standard backend.
Also, enable new LIKE selectivity estimators by default. Unrelated
change, but as long as I had to force initdb anyway...
PostgreSQL-7.0.2 run on Linux for the Intel-IA64 architecture. It also
fixes a bug in the configure scripts that caused configure to fail on
the fcntl(F_SETLK) test.
This fix triggered a bug in the fcntl(F_SETLK) code of the Linux
kernel when used on unix domain sockets resulting in postmaster to
segfault immediately after startup. There is a fix available and
included in the kernel that will be on SuSE Linux 7.0, but kernels <=
2.2.16 still have this bug.
Reinhard Max
for details). It doesn't really do that much yet, since there are no
short-term memory contexts in the executor, but the infrastructure is
in place and long-term contexts are handled reasonably. A few long-
standing bugs have been fixed, such as 'VACUUM; anything' in a single
query string crashing. Also, out-of-memory is now considered a
recoverable ERROR, not FATAL.
Eliminate a large amount of crufty, now-dead code in and around
memory management.
Fix problem with holding off SIGTRAP, SIGSEGV, etc in postmaster and
backend startup.
inputs have been converted to newstyle. This should go a long way towards
fixing our portability problems with platforms where char and short
parameters are passed differently from int-width parameters. Still
more to do for the Alpha port however.
it will close VFDs if necessary to surmount ENFILE or EMFILE failures.
Make use of this in md.c, xlog.c, and user.c routines that were
formerly vulnerable to these failures. In particular, this should
handle failures of mdblindwrt() that have been observed under heavy
load conditions. (By golly, every other process on the system may
crash after Postgres eats up all the kernel FDs, but Postgres will
keep going!)
That means you can now set your options in either or all of $PGDATA/configuration,
some postmaster option (--enable-fsync=off), or set a SET command. The list of
options is in backend/utils/misc/guc.c, documentation will be written post haste.
pg_options is gone, so is that pq_geqo config file. Also removed were backend -K,
-Q, and -T options (no longer applicable, although -d0 does the same as -Q).
Added to configure an --enable-syslog option.
changed all callers from TPRINTF to elog(DEBUG)
Hiroshi. ReleaseRelationBuffers now removes rel's buffers from pool,
instead of merely marking them nondirty. The old code would leave valid
buffers for a deleted relation, which didn't cause any known problems
but can't possibly be a good idea. There were several places which called
ReleaseRelationBuffers *and* FlushRelationBuffers, which is now
unnecessary; but there were others that did not. FlushRelationBuffers
no longer emits a warning notice if it finds dirty buffers to flush,
because with the current bufmgr behavior that's not an unexpected
condition. Also, FlushRelationBuffers will flush out all dirty buffers
for the relation regardless of block number. This ensures that
pg_upgrade's expectations are met about tuple on-row status bits being
up-to-date on disk. Lastly, tweak BufTableDelete() to clear the
buffer's tag so that no one can mistake it for being a still-valid
buffer for the page it once held. Formerly, the buffer would not be
found by buffer hashtable searches after BufTableDelete(), but it would
still be thought to belong to its old relation by the routines that
sequentially scan the shared-buffer array. Again I know of no bugs
caused by that, but it still can't be a good idea.
whether to do fsync or not, and if so (which should be seldom) just
do the fsync immediately. This way we need not build data structures
in md.c/fd.c for blind writes.
as a shared dirtybit for each shared buffer. The shared dirtybit still
controls writing the buffer, but the local bit controls whether we need
to fsync the buffer's file. This arrangement fixes a bug that allowed
some required fsyncs to be missed, and should improve performance as well.
For more info see my post of same date on pghackers.