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* Update copyright notices for year 2012.Bruce Momjian2012-01-01
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* Cleanup for pull-up-isReset patch.Tom Lane2011-05-24
| | | | | | | | Clear isReset before, not after, calling the context-specific alloc method, so as to preserve the option to do a tail call in MemoryContextAlloc (and also so this code isn't assuming that a failed alloc call won't have changed the context's state before failing). Fix missed direct invocation of reset method. Reformat a comment.
* Pull up isReset flag from AllocSetContext to MemoryContext struct. ThisHeikki Linnakangas2011-05-21
| | | | | | | | | avoids the overhead of one function call when calling MemoryContextReset(), and it seems like the isReset optimization would be applicable to any new memory context we might invent in the future anyway. This buys back the overhead I just added in previous patch to always call MemoryContextReset() in ExecScan, even when there's no quals or projections.
* Improve aset.c's space management in contexts with small maxBlockSize.Tom Lane2011-05-02
| | | | | | | | | | | | | | | | | The previous coding would allow requests up to half of maxBlockSize to be treated as "chunks", but when that actually did happen, we'd waste nearly half of the space in the malloc block containing the chunk, if no smaller requests came along to fill it. Avoid this scenario by limiting the maximum size of a chunk to 1/8th maxBlockSize, so that we can waste no more than 1/8th of the allocated space. This will not change the behavior at all for the default context size parameters (with large maxBlockSize), but it will change the behavior when using ALLOCSET_SMALL_MAXSIZE. In particular, there's no longer a need for spell.c to be overly concerned about the request size parameters it uses, so remove a rather unhelpful comment about that. Merlin Moncure, per an idea of Tom Lane's
* pgindent run before PG 9.1 beta 1.Bruce Momjian2011-04-10
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* Stamp copyrights for year 2011.Bruce Momjian2011-01-01
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* Remove cvs keywords from all files.Magnus Hagander2010-09-20
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* pgindent run for 9.0Bruce Momjian2010-02-26
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* Update copyright for the year 2010.Bruce Momjian2010-01-02
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* Silence compiler warning on 64-bit windows buildMagnus Hagander2010-01-01
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* Speed up AllocSetFreeIndex, which is a significant cost in palloc and pfree,Tom Lane2009-07-21
| | | | | | | | | | by using a lookup table instead of a naive shift-and-count loop. Based on code originally posted by Sean Eron Anderson at http://graphics.stanford.edu/%7eseander/bithacks.html. Greg Stark did the research and benchmarking to show that this is what we should use. Jeremy Kerr first noticed that this is a hotspot that could be optimized, though we ended up not using his suggestion of platform-specific bit-searching code.
* 8.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef listBruce Momjian2009-06-11
| | | | provided by Andrew.
* Update copyright for 2009.Bruce Momjian2009-01-01
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* Add some debug support code to try to catch future mistakes in the area ofTom Lane2008-04-11
| | | | | | | | | | input functions that include garbage bytes in their results. Provide a compile-time option RANDOMIZE_ALLOCATED_MEMORY to make palloc fill returned blocks with variable contents. This option also makes the parser perform conversions of literal constants twice and compare the results, emitting a WARNING if they don't match. (This is the code I used to catch the input function bugs fixed in the previous commit.) For the moment, I've set it to be activated automatically by --enable-cassert.
* Update copyrights in source tree to 2008.Bruce Momjian2008-01-01
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* pgindent run for 8.3.Bruce Momjian2007-11-15
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* Remove an "optimization" I installed in 2001, to make repalloc() attempt toTom Lane2007-08-12
| | | | | | | | | | | | enlarge the memory chunk in-place when it was feasible to do so. This turns out to not work well at all for scenarios involving repeated cycles of palloc/repalloc/pfree: the eventually freed chunks go into the wrong freelist for the next initial palloc request, and so we consume memory indefinitely. While that could be defended against, the number of cases where the optimization can still be applied drops significantly, and adjusting the initial sizes of StringInfo buffers makes it drop to almost nothing. Seems better to just remove the extra complexity. Per recent discussion and testing.
* Adjust the output of MemoryContextStats() so that the stats for aNeil Conway2007-08-07
| | | | | | child memory contexts is indented two spaces to the right of its parent context. This should make it easier to deduce the memory context hierarchy from the output of MemoryContextStats().
* Marginal performance hack: remove the loop that used to be needed toTom Lane2007-04-30
| | | | | | | | | | | look through a freelist for a chunk of adequate size. For a long time now, all elements of a given freelist have been exactly the same allocated size, so we don't need a loop. Since the loop never iterated more than once, you'd think this wouldn't matter much, but it makes a noticeable savings in a simple test --- perhaps because the compiler isn't optimizing on a mistaken assumption that the loop would repeat. AllocSetAlloc is called often enough that saving even a couple of instructions is worthwhile.
* Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian2007-01-05
| | | | back-stamped for this.
* Improve memory management code to avoid inefficient behavior when a contextTom Lane2006-12-27
| | | | | | | | | | | | | | | has a small maxBlockSize: the maximum request size that we will treat as a "chunk" needs to be limited to fit in maxBlockSize. Otherwise we will round up the request size to the next power of 2, wasting space, which is a bit pointless if we aren't going to make the blocks big enough to fit additional stuff in them. The example motivating this is local buffer management, which makes repeated allocations of 8K (one BLCKSZ buffer) in TopMemoryContext, which has maxBlockSize = 8K because for the most part allocations there are small. This leads to each local buffer actually eating 16K of space, which adds up when there are thousands of them. I intend to change localbuf.c to aggregate its requests, which will prevent this particular misbehavior, but it seems likely that similar scenarios could arise elsewhere, so fixing the core problem seems wise as well.
* Modify aset.c to track the next intended block allocation size explicitly.Tom Lane2006-11-08
| | | | | | | | The former coding relied on the actual allocated size of the last block, which made it behave strangely if the first allocation in a context was larger than ALLOC_CHUNK_LIMIT: subsequent allocations would be referenced to that and not to the intended series of block sizes. Noted while studying a memory wastage gripe from Tatsuo.
* pgindent run for 8.2.Bruce Momjian2006-10-04
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* Fix typo in comment.Neil Conway2006-06-28
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* Update copyright for 2006. Update scripts.Bruce Momjian2006-03-05
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* AllocSetStats should probably be using unsigned format to show space totals.Tom Lane2006-02-14
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* Standard pgindent run for 8.1.Bruce Momjian2005-10-15
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* Short-circuit AllocSetReset if nothing has been palloc'd in the memoryTom Lane2005-09-01
| | | | | context since the previous AllocSetReset. Original patch by Atsushi Ogawa, editorialized on a little bit by Tom Lane.
* Back out patch:Bruce Momjian2005-06-04
| | | | | | | | | | | | | | | | | | | | --------------------------------------------------------------------------- Tom Lane <tgl@sss.pgh.pa.us> writes: > a_ogawa <a_ogawa@hi-ho.ne.jp> writes: > > It is a reasonable idea. However, the majority part of MemSet was not > > able to be avoided by this idea. Because the per-tuple contexts are used > > at the early stage of executor. > > Drat. Well, what about changing that? We could introduce additional > contexts or change the startup behavior so that the ones that are > frequently reset don't have any data in them unless you are working > with pass-by-ref values inside the inner loop. That might be possible. However, I think that we should change only aset.c about this article. I thought further: We can check whether context was used from the last reset even when blocks list is not empty. Please see attached patch.
* Tom Lane <tgl@sss.pgh.pa.us> writes:Bruce Momjian2005-06-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | > a_ogawa <a_ogawa@hi-ho.ne.jp> writes: > > It is a reasonable idea. However, the majority part of MemSet was not > > able to be avoided by this idea. Because the per-tuple contexts are used > > at the early stage of executor. > > Drat. Well, what about changing that? We could introduce additional > contexts or change the startup behavior so that the ones that are > frequently reset don't have any data in them unless you are working > with pass-by-ref values inside the inner loop. That might be possible. However, I think that we should change only aset.c about this article. I thought further: We can check whether context was used from the last reset even when blocks list is not empty. Please see attached patch. The effect of the patch that I measured is as follows: o Execution time that executed the SQL ten times. (1)Linux(CPU: Pentium III, Compiler option: -O2) - original: 24.960s - patched : 23.114s (2)Linux(CPU: Pentium 4, Compiler option: -O2) - original: 8.730s - patched : 7.962s (3)Solaris(CPU: Ultra SPARC III, Compiler option: -O2) - original: 37.0s - patched : 33.7s Atsushi Ogawa (a_ogawa)
* Minor speed hacks in AllocSetReset: avoid clearing the freelist headersTom Lane2005-05-14
| | | | | | | | | when the blocks list is empty (there can surely be no freelist items if the context contains no memory), and use MemSetAligned not MemSet to clear the headers (we assume alignof(pointer) >= alignof(int32)). Per discussion with Atsushi Ogawa. He proposes some further hacking that I'm not yet sold on, but these two changes are unconditional wins since there is no case in which they make things slower.
* Tag appropriate files for rc3PostgreSQL Daemon2004-12-31
| | | | | | | | Also performed an initial run through of upgrading our Copyright date to extend to 2005 ... first run here was very simple ... change everything where: grep 1996-2004 && the word 'Copyright' ... scanned through the generated list with 'less' first, and after, to make sure that I only picked up the right entries ...
* Add some marginal tweaks to eliminate memory leakages associated withTom Lane2004-09-16
| | | | | subtransactions. Trivial subxacts (such as a plpgsql exception block containing no database access) now demonstrably leak zero bytes.
* Pgindent run for 8.0.Bruce Momjian2004-08-29
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* Update copyright to 2004.Bruce Momjian2004-08-29
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* Reduce the minimum allocable chunk size to 8 bytes (from 16). Now thatTom Lane2004-05-26
| | | | | | | ListCells are only 8 bytes instead of 12 (on 4-byte-pointer machines anyway), it's worth maintaining a separate freelist for 8-byte objects. Remembering that alloc chunks carry 8 bytes of overhead, this should reduce the net storage requirement for a long List by about a third.
* $Header: -> $PostgreSQL Changes ...PostgreSQL Daemon2003-11-29
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* Avoid corner cases where aset.c would unnecessarily make malloc()Tom Lane2003-09-13
| | | | | requests of sizes that aren't powers of 2. Per observation from David Schultz, 28-Aug.
* Update copyrights to 2003.Bruce Momjian2003-08-04
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* pgindent run.Bruce Momjian2003-08-04
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* Error message editing in backend/utils (except /adt).Tom Lane2003-07-25
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* Tweak default memory context allocation policy so that a context is notTom Lane2002-12-15
| | | | | | | | | given any malloc block until something is first allocated in it; but thereafter, MemoryContextReset won't release that first malloc block. This preserves the quick-reset property of the original policy, without forcing 8K to be allocated to every context whether any of it is ever used or not. Also, remove some more no-longer-needed explicit freeing during ExecEndPlan.
* pgindent run.Bruce Momjian2002-09-04
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* Change memory-space accounting mechanism in tuplesort.c and tuplestore.cTom Lane2002-08-12
| | | | | | | | to make a reasonable attempt at accounting for palloc overhead, not just the requested size of each memory chunk. Since in many scenarios this will make for a significant reduction in the amount of space acquired, partially compensate by doubling the default value of SORT_MEM to 1Mb. Per discussion in pgsql-general around 9-Jun-2002..
* Update copyright to 2002.Bruce Momjian2002-06-20
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* Change made to elog:Bruce Momjian2002-03-06
| | | | | | | | | | | | | | | | | | | o Change all current CVS messages of NOTICE to WARNING. We were going to do this just before 7.3 beta but it has to be done now, as you will see below. o Change current INFO messages that should be controlled by client_min_messages to NOTICE. o Force remaining INFO messages, like from EXPLAIN, VACUUM VERBOSE, etc. to always go to the client. o Remove INFO from the client_min_messages options and add NOTICE. Seems we do need three non-ERROR elog levels to handle the various behaviors we need for these messages. Regression passed.
* New pgindent run with fixes suggested by Tom. Patch manually reviewed,Bruce Momjian2001-11-05
| | | | initdb/regression tests pass.
* Another pgindent run. Fixes enum indenting, and improves #endifBruce Momjian2001-10-28
| | | | spacing. Also adds space for one-line comments.
* pgindent run on all C files. Java run to follow. initdb/regressionBruce Momjian2001-10-25
| | | | tests pass.
* pgindent run. Make it all clean.Bruce Momjian2001-03-22
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