I believe I fixed all flaws mentioned so far (see attachment).
Also I did a new benchmark to make sure that new patch makes PostgreSQL
work faster and doesn't cause performance degradation in some cases.
"usual pgbench" row corresponds to `pgbench -j 8 -c 8 -T 30 pgbench`
performed on a 4-core PC.
"N partitions" rows correspond to a benchmark described in a first
message of this thread performed on the same PC. N is and argument
given to gen.pl script i.e. number of partitions in generated
partitioned table.
Here are results (3 tests, TPS excluding connections establishing):
Test | Before | After | Delta avg
----------------|-----------|-----------|-------------
| 295.7 | 295.0 |
usual pgbench | 303.1 | 299.6 | ~ 0%
| 297.7 | 302.7 |
----------------|-----------|-----------|-------------
| 28022.3 | 27956.1 |
10 partitions | 27550.1 | 28916.9 | ~ 0%
| 28617.0 | 28022.9 |
----------------|-----------|-----------|-------------
| 3021.4 | 3184.0 |
100 partitions | 2949.1 | 3120.1 | 3% more TPS
| 2870.6 | 2825.2 |
----------------|-----------|-----------|-------------
| 106.7 | 158.6 |
1000 partitions | 105.2 | 168.4 | 53% more TPS
| 105.9 | 162.0 |
On Fri, 18 Dec 2015 13:39:01 -0500
Tom Lane <t...@sss.pgh.pa.us> wrote:
> Robert Haas <robertmh...@gmail.com> writes:
> > I don't know, I'm still not very comfortable with this. And Tom
> > didn't like dictating that hash_any() must be no-fail, though I'm
> > not sure why.
>
> What I definitely didn't like was assuming at a distance that it would
> be no-fail. If we're to depend on that, the patch had better attach
> a comment saying so to the header comments of the function(s) it's
> assuming that about. Otherwise, somebody could hack up hashfunc.c
> in a way that breaks the assumption, without any clue that some code
> in a very-far-away module is critically reliant on it.
>
> > Let's wait to see what others think.
>
> A few observations:
>
> * This bit is too cute by half, if not three-quarters:
>
> + uint32 itemsizelg:2; /* sizeof one
> item log 2 */
> + uint32 capacity:30; /* capacity of
> array */
>
> Is there a good reason to assume that the only things we'll ever store
> in these arrays are of size no more than 8 bytes? Are we so desperate
> to save space that we cannot spare two separate words for itemsize and
> capacity? (ISTM it's a good bet that the extra code for accessing
> these bitfields occupies more space than would be saved, considering
> how few ResourceOwners typically exist at one time.) Let's just make
> it a couple of ints and be done. Actually, maybe nitems and capacity
> should be size_t, just in case.
>
> * An alternative design would be to forget itemsizelg altogether and
> insist that everything stored in the resource arrays be a Datum,
> which could then be coerced to/from some form of integer or some form
> of pointer as appropriate. That would waste some space in the int
> case, but it would considerably simplify both the ResourceArray code
> and the APIs to it, which might be worth the price of assuming we'll
> never store anything bigger than 8 bytes. It also would make this
> look more like some existing APIs such as the on_exit callbacks.
>
> * A lot of the code churn comes from the insistence on defining
> callbacks, which I'm dubious that we need. We could instead have a
> function that is "get any convenient one of the array elements" and
> revise the loops in ResourceOwnerReleaseInternal to be like
>
> while ((item = getconvenientitem(resourcearray)))
> {
> drop item in exactly the same way as before
> }
>
> I find that preferable to the proposed ResourceArrayRemoveAll
>
> + while (resarr->nitems > 0)
> + {
> + releasecb(resarr->itemsarr, isCommit);
> + }
>
> which certainly looks like it's an infinite loop; it's assuming (again
> with no documentation) that the callback function will cause the array
> to get smaller somehow. With the existing coding, it's much more
> clear why we think the loops will terminate.
>
> * The reason that ResourceOwnerReleaseInternal was not horribly
> inefficient was that its notion of "any convenient one" of the items
> to be deleted next was in fact the one that the corresponding Forget
> function would examine first, thus avoiding an O(N^2) cost to
> re-identify the item to be dropped. I think we should make an effort
> to be more explicit about that connection in any rewrite. In
> particular, it looks to me like when a hash array is in use, things
> will get slower not faster because we'll be adding a hash lookup step
> to each forget operation. Maybe we should consider adjusting the
> APIs so that that can be avoided. Or possibly we could have internal
> state in the ResourceArrays that says "we expect this item to be
> dropped in a moment, check that before going to the trouble of a hash
> lookup".
>
> * Actually, I'm not convinced that the proposed reimplementation of
> ResourceArrayRemove isn't horribly slow much of the time. It sure
> looks like it could degrade to a linear search very easily.
>
> * I still say that the assumption embodied as
> RESOURCE_ARRAY_ZERO_ELEMENT (ie that no valid entry is all-zero-bits)
> is pretty unacceptable. It might work for pointers, but I don't like
> it for resources represented by integer indexes.
>
> regards, tom lane
>
>
diff --git a/src/backend/access/hash/hashfunc.c b/src/backend/access/hash/hashfunc.c
index 9ee654e..5a00a03 100644
--- a/src/backend/access/hash/hashfunc.c
+++ b/src/backend/access/hash/hashfunc.c
@@ -297,6 +297,9 @@ hashvarlena(PG_FUNCTION_ARGS)
* of 2. There is no need to do mod a prime (mod is sooo slow!).
* If you need less than 32 bits, use a bitmask.
*
+ * This procedure never fails. Its important. Some code notably ResourceOwner
+ * relies on this.
+ *
* Note: we could easily change this function to return a 64-bit hash value
* by using the final values of both b and c. b is perhaps a little less
* well mixed than c, however.
diff --git a/src/backend/utils/resowner/resowner.c b/src/backend/utils/resowner/resowner.c
index 0e7acbf..abed36c 100644
--- a/src/backend/utils/resowner/resowner.c
+++ b/src/backend/utils/resowner/resowner.c
@@ -29,6 +29,219 @@
#include "utils/snapmgr.h"
/*
+ * ResourceArray is a common structure for storing different types of resources.
+ *
+ * ResourceOwner can own `HeapTuple`s, `Relation`s, `Snapshot`s, etc. For
+ * each resource type there are procedures ResourceOwnerRemember* and
+ * ResourceOwnerForget*. There are also ResourceOwnerEnlarge* procedures
+ * which should be called before corresponding ResourceOwnerRemember* calls
+ * (see below). Internally each type of resource is stored in separate
+ * ResourceArray.
+ *
+ * There are two major reasons for using ResourceArray instead of, say,
+ * regular C arrays.
+ *
+ * Firstly we would like to prevent code duplication. For instance
+ * ResourceArray provides generic Remember/Forget/Enlarge procedures, so
+ * corresponding ResourceOwner* procedures are just a typesafe wrappers for
+ * these procedures.
+ *
+ * Secondly ResourceArray must be more efficient than regular C array.
+ * Current implementation in general could be considered a hash table. It has
+ * O(1) complexity of both Remember and Forget procedures.
+ */
+typedef struct ResourceArray
+{
+ Datum *itemsarr; /* buffer for storing values */
+ Datum invalidval; /* value that is considered invalid */
+ uint32 capacity; /* capacity of array */
+ uint32 nitems; /* how many items is stored in items array */
+ uint32 maxitems; /* precalculated RESARRAY_MAX_ITEMS(capacity) */
+ uint32 lastidx; /* index of last item returned by GetAny */
+} ResourceArray;
+
+/*
+ * This number is used as initial size of resource array. If given number of
+ * items is not enough, we double array size and reallocate memory.
+ *
+ * Should be power of two since we use (arrsize - 1) as mask for hash value.
+ *
+ */
+#define RESARRAY_INIT_SIZE 16
+
+/*
+ * How many items could be stored in a resource array of given capacity. If
+ * this number is reached we need to resize an array to prevent hash collisions.
+ *
+ * This computation actually costs only two additions and one binary shift.
+ */
+#define RESARRAY_MAX_ITEMS(capacity) ((capacity)*3/4)
+
+/*
+ * Initialize ResourceArray
+ */
+static void
+ResourceArrayInit(ResourceArray * resarr, Datum invalidval)
+{
+ Assert(resarr->itemsarr == NULL);
+ Assert(resarr->capacity == 0);
+ Assert(resarr->nitems == 0);
+ Assert(resarr->maxitems == 0);
+ Assert(resarr->invalidval == 0);
+ Assert(resarr->lastidx == 0);
+
+ resarr->invalidval = invalidval;
+}
+
+/*
+ * Add a resource to ResourceArray
+ *
+ * Caller must have previously done ResourceArrayEnlarge()
+ */
+static void
+ResourceArrayAdd(ResourceArray * resarr, Datum data)
+{
+ Datum idx;
+ Datum mask = resarr->capacity - 1;
+
+ Assert(resarr->maxitems > resarr->nitems);
+ Assert(resarr->capacity > 0);
+ Assert(resarr->itemsarr != NULL);
+ Assert(data != resarr->invalidval);
+
+ idx = hash_any((void *) &data, sizeof(data)) & mask;
+
+ while (true)
+ {
+ if (resarr->itemsarr[idx] == resarr->invalidval)
+ break;
+ idx = (idx + 1) & mask;
+ }
+
+ resarr->itemsarr[idx] = data;
+ resarr->nitems++;
+}
+
+/*
+ * Remove a resource from ResourceArray
+ *
+ * Returns true on success, false if resource was not found
+ */
+static bool
+ResourceArrayRemove(ResourceArray * resarr, Datum data)
+{
+ uint32 i;
+ Datum idx;
+ Datum mask = resarr->capacity - 1;
+
+ Assert(resarr->capacity > 0);
+ Assert(resarr->itemsarr != NULL);
+ Assert(data != resarr->invalidval);
+
+ idx = hash_any((void *) &data, sizeof(data)) & mask;
+ for (i = 0; i < resarr->capacity; i++)
+ {
+ if (resarr->itemsarr[idx] == data)
+ {
+ resarr->itemsarr[idx] = resarr->invalidval;
+ resarr->nitems--;
+ return true;
+ }
+ idx = (idx + 1) & mask;
+ }
+
+ return false;
+}
+
+/*
+ * Make sure there is a room for at least one more resource in an array.
+ *
+ * This is separate from actually inserting a resource because if we run out
+ * of memory, it's critical to do so *before* acquiring the resource.
+ */
+static void
+ResourceArrayEnlarge(ResourceArray * resarr)
+{
+ uint32 i,
+ oldcap;
+ Datum *olditemsarr;
+
+ if (resarr->nitems < resarr->maxitems)
+ return; /* nothing to do */
+
+ olditemsarr = resarr->itemsarr;
+ oldcap = resarr->capacity;
+
+ resarr->capacity = oldcap > 0 ? oldcap * 2 : RESARRAY_INIT_SIZE;
+ resarr->itemsarr = (Datum *)
+ MemoryContextAlloc(TopMemoryContext,
+ resarr->capacity * sizeof(Datum));
+ resarr->maxitems = RESARRAY_MAX_ITEMS(resarr->capacity);
+ resarr->nitems = 0;
+
+ for (i = 0; i < resarr->capacity; i++)
+ resarr->itemsarr[i] = resarr->invalidval;
+
+ if (olditemsarr != NULL)
+ {
+ while (oldcap > 0)
+ {
+ oldcap--;
+ if (olditemsarr[oldcap] != resarr->invalidval)
+ ResourceArrayAdd(resarr, olditemsarr[oldcap]);
+ }
+ pfree(olditemsarr);
+ }
+}
+
+/*
+ * Get any convenient element.
+ *
+ * Returns true on success, false on failure.
+ */
+static bool
+ResourceArrayGetAny(ResourceArray * resarr, Datum *out)
+{
+ uint32 mask;
+
+ if (resarr->nitems == 0)
+ return false;
+
+ Assert(resarr->capacity > 0);
+ mask = resarr->capacity - 1;
+
+ for (;;)
+ {
+ resarr->lastidx = resarr->lastidx & mask;
+ if (resarr->itemsarr[resarr->lastidx] != resarr->invalidval)
+ break;
+
+ resarr->lastidx++;
+ }
+
+ *out = resarr->itemsarr[resarr->lastidx];
+ return true;
+}
+
+/*
+ * Return ResourceArray to initial state
+ */
+static void
+ResourceArrayFree(ResourceArray * resarr)
+{
+ Assert(resarr->nitems == 0);
+
+ resarr->capacity = 0;
+ resarr->maxitems = 0;
+
+ if (!resarr->itemsarr)
+ return;
+
+ pfree(resarr->itemsarr);
+ resarr->itemsarr = NULL;
+}
+
+/*
* To speed up bulk releasing or reassigning locks from a resource owner to
* its parent, each resource owner has a small cache of locks it owns. The
* lock manager has the same information in its local lock hash table, and
@@ -56,53 +269,22 @@ typedef struct ResourceOwnerData
ResourceOwner nextchild; /* next child of same parent */
const char *name; /* name (just for debugging) */
- /* We have built-in support for remembering owned buffers */
- int nbuffers; /* number of owned buffer pins */
- Buffer *buffers; /* dynamically allocated array */
- int maxbuffers; /* currently allocated array size */
-
/* We can remember up to MAX_RESOWNER_LOCKS references to local locks. */
int nlocks; /* number of owned locks */
LOCALLOCK *locks[MAX_RESOWNER_LOCKS]; /* list of owned locks */
- /* We have built-in support for remembering catcache references */
- int ncatrefs; /* number of owned catcache pins */
- HeapTuple *catrefs; /* dynamically allocated array */
- int maxcatrefs; /* currently allocated array size */
-
- int ncatlistrefs; /* number of owned catcache-list pins */
- CatCList **catlistrefs; /* dynamically allocated array */
- int maxcatlistrefs; /* currently allocated array size */
-
- /* We have built-in support for remembering relcache references */
- int nrelrefs; /* number of owned relcache pins */
- Relation *relrefs; /* dynamically allocated array */
- int maxrelrefs; /* currently allocated array size */
-
- /* We have built-in support for remembering plancache references */
- int nplanrefs; /* number of owned plancache pins */
- CachedPlan **planrefs; /* dynamically allocated array */
- int maxplanrefs; /* currently allocated array size */
-
- /* We have built-in support for remembering tupdesc references */
- int ntupdescs; /* number of owned tupdesc references */
- TupleDesc *tupdescs; /* dynamically allocated array */
- int maxtupdescs; /* currently allocated array size */
-
- /* We have built-in support for remembering snapshot references */
- int nsnapshots; /* number of owned snapshot references */
- Snapshot *snapshots; /* dynamically allocated array */
- int maxsnapshots; /* currently allocated array size */
-
- /* We have built-in support for remembering open temporary files */
- int nfiles; /* number of owned temporary files */
- File *files; /* dynamically allocated array */
- int maxfiles; /* currently allocated array size */
-
- /* We have built-in support for remembering dynamic shmem segments */
- int ndsms; /* number of owned shmem segments */
- dsm_segment **dsms; /* dynamically allocated array */
- int maxdsms; /* currently allocated array size */
+ /* We have built-in support for remembering: */
+
+ ResourceArray catrefarr; /* `HeapTuple`s */
+ ResourceArray catlistrefarr; /* `ResourceOwner`s */
+ ResourceArray relrefarr; /* `Relation`s */
+ ResourceArray planrefarr; /* `CachedPlan*`s */
+ ResourceArray tupdescarr; /* `TupleDesc`s */
+ ResourceArray snapshotarr; /* `Snapshot`s */
+ ResourceArray dsmarr; /* `dsm_segment*`s */
+ ResourceArray bufferarr; /* `Buffer`s */
+ ResourceArray filearr; /* `File`s */
+
} ResourceOwnerData;
@@ -168,6 +350,16 @@ ResourceOwnerCreate(ResourceOwner parent, const char *name)
parent->firstchild = owner;
}
+ ResourceArrayInit(&(owner->catrefarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->catlistrefarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->relrefarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->planrefarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->tupdescarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->snapshotarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->dsmarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->bufferarr), (Datum) (InvalidBuffer));
+ ResourceArrayInit(&(owner->filearr), (Datum) (-1));
+
return owner;
}
@@ -229,6 +421,7 @@ ResourceOwnerReleaseInternal(ResourceOwner owner,
ResourceOwner child;
ResourceOwner save;
ResourceReleaseCallbackItem *item;
+ Datum foundres;
/* Recurse to handle descendants */
for (child = owner->firstchild; child != NULL; child = child->nextchild)
@@ -252,45 +445,34 @@ ResourceOwnerReleaseInternal(ResourceOwner owner,
* During a commit, there shouldn't be any remaining pins --- that
* would indicate failure to clean up the executor correctly --- so
* issue warnings. In the abort case, just clean up quietly.
- *
- * We are careful to do the releasing back-to-front, so as to avoid
- * O(N^2) behavior in ResourceOwnerForgetBuffer().
*/
- while (owner->nbuffers > 0)
+ while (ResourceArrayGetAny(&(owner->bufferarr), &foundres))
{
+ Buffer res = (Buffer) foundres;
+
if (isCommit)
- PrintBufferLeakWarning(owner->buffers[owner->nbuffers - 1]);
- ReleaseBuffer(owner->buffers[owner->nbuffers - 1]);
+ PrintBufferLeakWarning(res);
+ ReleaseBuffer(res);
}
- /*
- * Release relcache references. Note that RelationClose will remove
- * the relref entry from my list, so I just have to iterate till there
- * are none.
- *
- * As with buffer pins, warn if any are left at commit time, and
- * release back-to-front for speed.
- */
- while (owner->nrelrefs > 0)
+ /* Ditto for relcache references. */
+ while (ResourceArrayGetAny(&(owner->relrefarr), &foundres))
{
+ Relation res = (Relation) foundres;
+
if (isCommit)
- PrintRelCacheLeakWarning(owner->relrefs[owner->nrelrefs - 1]);
- RelationClose(owner->relrefs[owner->nrelrefs - 1]);
+ PrintRelCacheLeakWarning(res);
+ RelationClose(res);
}
- /*
- * Release dynamic shared memory segments. Note that dsm_detach()
- * will remove the segment from my list, so I just have to iterate
- * until there are none.
- *
- * As in the preceding cases, warn if there are leftover at commit
- * time.
- */
- while (owner->ndsms > 0)
+ /* Ditto for dynamic shared memory segments */
+ while (ResourceArrayGetAny(&(owner->dsmarr), &foundres))
{
+ dsm_segment *res = (dsm_segment *) foundres;
+
if (isCommit)
- PrintDSMLeakWarning(owner->dsms[owner->ndsms - 1]);
- dsm_detach(owner->dsms[owner->ndsms - 1]);
+ PrintDSMLeakWarning(res);
+ dsm_detach(res);
}
}
else if (phase == RESOURCE_RELEASE_LOCKS)
@@ -351,47 +533,63 @@ ResourceOwnerReleaseInternal(ResourceOwner owner,
* As with buffer pins, warn if any are left at commit time, and
* release back-to-front for speed.
*/
- while (owner->ncatrefs > 0)
+ while (ResourceArrayGetAny(&(owner->catrefarr), &foundres))
{
+ HeapTuple res = (HeapTuple) foundres;
+
if (isCommit)
- PrintCatCacheLeakWarning(owner->catrefs[owner->ncatrefs - 1]);
- ReleaseCatCache(owner->catrefs[owner->ncatrefs - 1]);
+ PrintCatCacheLeakWarning(res);
+ ReleaseCatCache(res);
}
+
/* Ditto for catcache lists */
- while (owner->ncatlistrefs > 0)
+ while (ResourceArrayGetAny(&(owner->catlistrefarr), &foundres))
{
+ CatCList *res = (CatCList *) foundres;
+
if (isCommit)
- PrintCatCacheListLeakWarning(owner->catlistrefs[owner->ncatlistrefs - 1]);
- ReleaseCatCacheList(owner->catlistrefs[owner->ncatlistrefs - 1]);
+ PrintCatCacheListLeakWarning(res);
+ ReleaseCatCacheList(res);
}
+
/* Ditto for plancache references */
- while (owner->nplanrefs > 0)
+ while (ResourceArrayGetAny(&(owner->planrefarr), &foundres))
{
+ CachedPlan *res = (CachedPlan *) foundres;
+
if (isCommit)
- PrintPlanCacheLeakWarning(owner->planrefs[owner->nplanrefs - 1]);
- ReleaseCachedPlan(owner->planrefs[owner->nplanrefs - 1], true);
+ PrintPlanCacheLeakWarning(res);
+ ReleaseCachedPlan(res, true);
}
+
/* Ditto for tupdesc references */
- while (owner->ntupdescs > 0)
+ while (ResourceArrayGetAny(&(owner->tupdescarr), &foundres))
{
+ TupleDesc res = (TupleDesc) foundres;
+
if (isCommit)
- PrintTupleDescLeakWarning(owner->tupdescs[owner->ntupdescs - 1]);
- DecrTupleDescRefCount(owner->tupdescs[owner->ntupdescs - 1]);
+ PrintTupleDescLeakWarning(res);
+ DecrTupleDescRefCount(res);
}
+
/* Ditto for snapshot references */
- while (owner->nsnapshots > 0)
+ while (ResourceArrayGetAny(&(owner->snapshotarr), &foundres))
{
+ Snapshot res = (Snapshot) foundres;
+
if (isCommit)
- PrintSnapshotLeakWarning(owner->snapshots[owner->nsnapshots - 1]);
- UnregisterSnapshot(owner->snapshots[owner->nsnapshots - 1]);
+ PrintSnapshotLeakWarning(res);
+ UnregisterSnapshot(res);
}
/* Ditto for temporary files */
- while (owner->nfiles > 0)
+ while (ResourceArrayGetAny(&(owner->filearr), &foundres))
{
+ File res = (File) foundres;
+
if (isCommit)
- PrintFileLeakWarning(owner->files[owner->nfiles - 1]);
- FileClose(owner->files[owner->nfiles - 1]);
+ PrintFileLeakWarning(res);
+ FileClose(res);
}
/* Clean up index scans too */
@@ -418,16 +616,7 @@ ResourceOwnerDelete(ResourceOwner owner)
Assert(owner != CurrentResourceOwner);
/* And it better not own any resources, either */
- Assert(owner->nbuffers == 0);
Assert(owner->nlocks == 0 || owner->nlocks == MAX_RESOWNER_LOCKS + 1);
- Assert(owner->ncatrefs == 0);
- Assert(owner->ncatlistrefs == 0);
- Assert(owner->nrelrefs == 0);
- Assert(owner->ndsms == 0);
- Assert(owner->nplanrefs == 0);
- Assert(owner->ntupdescs == 0);
- Assert(owner->nsnapshots == 0);
- Assert(owner->nfiles == 0);
/*
* Delete children. The recursive call will delink the child from me, so
@@ -444,25 +633,15 @@ ResourceOwnerDelete(ResourceOwner owner)
ResourceOwnerNewParent(owner, NULL);
/* And free the object. */
- if (owner->buffers)
- pfree(owner->buffers);
- if (owner->catrefs)
- pfree(owner->catrefs);
- if (owner->catlistrefs)
- pfree(owner->catlistrefs);
- if (owner->relrefs)
- pfree(owner->relrefs);
- if (owner->planrefs)
- pfree(owner->planrefs);
- if (owner->tupdescs)
- pfree(owner->tupdescs);
- if (owner->snapshots)
- pfree(owner->snapshots);
- if (owner->files)
- pfree(owner->files);
- if (owner->dsms)
- pfree(owner->dsms);
-
+ ResourceArrayFree(&(owner->catrefarr));
+ ResourceArrayFree(&(owner->catlistrefarr));
+ ResourceArrayFree(&(owner->relrefarr));
+ ResourceArrayFree(&(owner->planrefarr));
+ ResourceArrayFree(&(owner->tupdescarr));
+ ResourceArrayFree(&(owner->snapshotarr));
+ ResourceArrayFree(&(owner->dsmarr));
+ ResourceArrayFree(&(owner->bufferarr));
+ ResourceArrayFree(&(owner->filearr));
pfree(owner);
}
@@ -575,26 +754,9 @@ UnregisterResourceReleaseCallback(ResourceReleaseCallback callback, void *arg)
void
ResourceOwnerEnlargeBuffers(ResourceOwner owner)
{
- int newmax;
-
- if (owner == NULL ||
- owner->nbuffers < owner->maxbuffers)
- return; /* nothing to do */
-
- if (owner->buffers == NULL)
- {
- newmax = 16;
- owner->buffers = (Buffer *)
- MemoryContextAlloc(TopMemoryContext, newmax * sizeof(Buffer));
- owner->maxbuffers = newmax;
- }
- else
- {
- newmax = owner->maxbuffers * 2;
- owner->buffers = (Buffer *)
- repalloc(owner->buffers, newmax * sizeof(Buffer));
- owner->maxbuffers = newmax;
- }
+ if (owner == NULL)
+ return;
+ ResourceArrayEnlarge(&(owner->bufferarr));
}
/*
@@ -608,12 +770,9 @@ ResourceOwnerEnlargeBuffers(ResourceOwner owner)
void
ResourceOwnerRememberBuffer(ResourceOwner owner, Buffer buffer)
{
- if (owner != NULL)
- {
- Assert(owner->nbuffers < owner->maxbuffers);
- owner->buffers[owner->nbuffers] = buffer;
- owner->nbuffers++;
- }
+ if (owner == NULL)
+ return;
+ ResourceArrayAdd(&(owner->bufferarr), (Datum) buffer);
}
/*
@@ -625,33 +784,15 @@ ResourceOwnerRememberBuffer(ResourceOwner owner, Buffer buffer)
void
ResourceOwnerForgetBuffer(ResourceOwner owner, Buffer buffer)
{
- if (owner != NULL)
- {
- Buffer *buffers = owner->buffers;
- int nb1 = owner->nbuffers - 1;
- int i;
+ bool res;
- /*
- * Scan back-to-front because it's more likely we are releasing a
- * recently pinned buffer. This isn't always the case of course, but
- * it's the way to bet.
- */
- for (i = nb1; i >= 0; i--)
- {
- if (buffers[i] == buffer)
- {
- while (i < nb1)
- {
- buffers[i] = buffers[i + 1];
- i++;
- }
- owner->nbuffers = nb1;
- return;
- }
- }
+ if (owner == NULL)
+ return;
+
+ res = ResourceArrayRemove(&(owner->bufferarr), (Datum) buffer);
+ if (!res)
elog(ERROR, "buffer %d is not owned by resource owner %s",
buffer, owner->name);
- }
}
/*
@@ -667,6 +808,8 @@ ResourceOwnerForgetBuffer(ResourceOwner owner, Buffer buffer)
void
ResourceOwnerRememberLock(ResourceOwner owner, LOCALLOCK *locallock)
{
+ Assert(locallock != NULL);
+
if (owner->nlocks > MAX_RESOWNER_LOCKS)
return; /* we have already overflowed */
@@ -714,25 +857,7 @@ ResourceOwnerForgetLock(ResourceOwner owner, LOCALLOCK *locallock)
void
ResourceOwnerEnlargeCatCacheRefs(ResourceOwner owner)
{
- int newmax;
-
- if (owner->ncatrefs < owner->maxcatrefs)
- return; /* nothing to do */
-
- if (owner->catrefs == NULL)
- {
- newmax = 16;
- owner->catrefs = (HeapTuple *)
- MemoryContextAlloc(TopMemoryContext, newmax * sizeof(HeapTuple));
- owner->maxcatrefs = newmax;
- }
- else
- {
- newmax = owner->maxcatrefs * 2;
- owner->catrefs = (HeapTuple *)
- repalloc(owner->catrefs, newmax * sizeof(HeapTuple));
- owner->maxcatrefs = newmax;
- }
+ ResourceArrayEnlarge(&(owner->catrefarr));
}
/*
@@ -743,9 +868,7 @@ ResourceOwnerEnlargeCatCacheRefs(ResourceOwner owner)
void
ResourceOwnerRememberCatCacheRef(ResourceOwner owner, HeapTuple tuple)
{
- Assert(owner->ncatrefs < owner->maxcatrefs);
- owner->catrefs[owner->ncatrefs] = tuple;
- owner->ncatrefs++;
+ ResourceArrayAdd(&(owner->catrefarr), (Datum) tuple);
}
/*
@@ -754,25 +877,12 @@ ResourceOwnerRememberCatCacheRef(ResourceOwner owner, HeapTuple tuple)
void
ResourceOwnerForgetCatCacheRef(ResourceOwner owner, HeapTuple tuple)
{
- HeapTuple *catrefs = owner->catrefs;
- int nc1 = owner->ncatrefs - 1;
- int i;
+ bool res = ResourceArrayRemove(&(owner->catrefarr),
+ (Datum) tuple);
- for (i = nc1; i >= 0; i--)
- {
- if (catrefs[i] == tuple)
- {
- while (i < nc1)
- {
- catrefs[i] = catrefs[i + 1];
- i++;
- }
- owner->ncatrefs = nc1;
- return;
- }
- }
- elog(ERROR, "catcache reference %p is not owned by resource owner %s",
- tuple, owner->name);
+ if (!res)
+ elog(ERROR, "catcache reference %p is not owned by resource owner %s",
+ tuple, owner->name);
}
/*
@@ -785,25 +895,7 @@ ResourceOwnerForgetCatCacheRef(ResourceOwner owner, HeapTuple tuple)
void
ResourceOwnerEnlargeCatCacheListRefs(ResourceOwner owner)
{
- int newmax;
-
- if (owner->ncatlistrefs < owner->maxcatlistrefs)
- return; /* nothing to do */
-
- if (owner->catlistrefs == NULL)
- {
- newmax = 16;
- owner->catlistrefs = (CatCList **)
- MemoryContextAlloc(TopMemoryContext, newmax * sizeof(CatCList *));
- owner->maxcatlistrefs = newmax;
- }
- else
- {
- newmax = owner->maxcatlistrefs * 2;
- owner->catlistrefs = (CatCList **)
- repalloc(owner->catlistrefs, newmax * sizeof(CatCList *));
- owner->maxcatlistrefs = newmax;
- }
+ ResourceArrayEnlarge(&(owner->catlistrefarr));
}
/*
@@ -814,9 +906,7 @@ ResourceOwnerEnlargeCatCacheListRefs(ResourceOwner owner)
void
ResourceOwnerRememberCatCacheListRef(ResourceOwner owner, CatCList *list)
{
- Assert(owner->ncatlistrefs < owner->maxcatlistrefs);
- owner->catlistrefs[owner->ncatlistrefs] = list;
- owner->ncatlistrefs++;
+ ResourceArrayAdd(&(owner->catlistrefarr), (Datum) list);
}
/*
@@ -825,25 +915,12 @@ ResourceOwnerRememberCatCacheListRef(ResourceOwner owner, CatCList *list)
void
ResourceOwnerForgetCatCacheListRef(ResourceOwner owner, CatCList *list)
{
- CatCList **catlistrefs = owner->catlistrefs;
- int nc1 = owner->ncatlistrefs - 1;
- int i;
+ bool res = ResourceArrayRemove(&(owner->catlistrefarr),
+ (Datum) list);
- for (i = nc1; i >= 0; i--)
- {
- if (catlistrefs[i] == list)
- {
- while (i < nc1)
- {
- catlistrefs[i] = catlistrefs[i + 1];
- i++;
- }
- owner->ncatlistrefs = nc1;
- return;
- }
- }
- elog(ERROR, "catcache list reference %p is not owned by resource owner %s",
- list, owner->name);
+ if (!res)
+ elog(ERROR, "catcache list reference %p is not owned by resource owner %s",
+ list, owner->name);
}
/*
@@ -856,25 +933,7 @@ ResourceOwnerForgetCatCacheListRef(ResourceOwner owner, CatCList *list)
void
ResourceOwnerEnlargeRelationRefs(ResourceOwner owner)
{
- int newmax;
-
- if (owner->nrelrefs < owner->maxrelrefs)
- return; /* nothing to do */
-
- if (owner->relrefs == NULL)
- {
- newmax = 16;
- owner->relrefs = (Relation *)
- MemoryContextAlloc(TopMemoryContext, newmax * sizeof(Relation));
- owner->maxrelrefs = newmax;
- }
- else
- {
- newmax = owner->maxrelrefs * 2;
- owner->relrefs = (Relation *)
- repalloc(owner->relrefs, newmax * sizeof(Relation));
- owner->maxrelrefs = newmax;
- }
+ ResourceArrayEnlarge(&(owner->relrefarr));
}
/*
@@ -885,9 +944,7 @@ ResourceOwnerEnlargeRelationRefs(ResourceOwner owner)
void
ResourceOwnerRememberRelationRef(ResourceOwner owner, Relation rel)
{
- Assert(owner->nrelrefs < owner->maxrelrefs);
- owner->relrefs[owner->nrelrefs] = rel;
- owner->nrelrefs++;
+ ResourceArrayAdd(&(owner->relrefarr), (Datum) rel);
}
/*
@@ -896,25 +953,12 @@ ResourceOwnerRememberRelationRef(ResourceOwner owner, Relation rel)
void
ResourceOwnerForgetRelationRef(ResourceOwner owner, Relation rel)
{
- Relation *relrefs = owner->relrefs;
- int nr1 = owner->nrelrefs - 1;
- int i;
+ bool res = ResourceArrayRemove(&(owner->relrefarr),
+ (Datum) rel);
- for (i = nr1; i >= 0; i--)
- {
- if (relrefs[i] == rel)
- {
- while (i < nr1)
- {
- relrefs[i] = relrefs[i + 1];
- i++;
- }
- owner->nrelrefs = nr1;
- return;
- }
- }
- elog(ERROR, "relcache reference %s is not owned by resource owner %s",
- RelationGetRelationName(rel), owner->name);
+ if (!res)
+ elog(ERROR, "relcache reference %s is not owned by resource owner %s",
+ RelationGetRelationName(rel), owner->name);
}
/*
@@ -937,25 +981,7 @@ PrintRelCacheLeakWarning(Relation rel)
void
ResourceOwnerEnlargePlanCacheRefs(ResourceOwner owner)
{
- int newmax;
-
- if (owner->nplanrefs < owner->maxplanrefs)
- return; /* nothing to do */
-
- if (owner->planrefs == NULL)
- {
- newmax = 16;
- owner->planrefs = (CachedPlan **)
- MemoryContextAlloc(TopMemoryContext, newmax * sizeof(CachedPlan *));
- owner->maxplanrefs = newmax;
- }
- else
- {
- newmax = owner->maxplanrefs * 2;
- owner->planrefs = (CachedPlan **)
- repalloc(owner->planrefs, newmax * sizeof(CachedPlan *));
- owner->maxplanrefs = newmax;
- }
+ ResourceArrayEnlarge(&(owner->planrefarr));
}
/*
@@ -966,9 +992,7 @@ ResourceOwnerEnlargePlanCacheRefs(ResourceOwner owner)
void
ResourceOwnerRememberPlanCacheRef(ResourceOwner owner, CachedPlan *plan)
{
- Assert(owner->nplanrefs < owner->maxplanrefs);
- owner->planrefs[owner->nplanrefs] = plan;
- owner->nplanrefs++;
+ ResourceArrayAdd(&(owner->planrefarr), (Datum) plan);
}
/*
@@ -977,25 +1001,12 @@ ResourceOwnerRememberPlanCacheRef(ResourceOwner owner, CachedPlan *plan)
void
ResourceOwnerForgetPlanCacheRef(ResourceOwner owner, CachedPlan *plan)
{
- CachedPlan **planrefs = owner->planrefs;
- int np1 = owner->nplanrefs - 1;
- int i;
+ bool res = ResourceArrayRemove(&(owner->planrefarr),
+ (Datum) plan);
- for (i = np1; i >= 0; i--)
- {
- if (planrefs[i] == plan)
- {
- while (i < np1)
- {
- planrefs[i] = planrefs[i + 1];
- i++;
- }
- owner->nplanrefs = np1;
- return;
- }
- }
- elog(ERROR, "plancache reference %p is not owned by resource owner %s",
- plan, owner->name);
+ if (!res)
+ elog(ERROR, "plancache reference %p is not owned by resource owner %s",
+ plan, owner->name);
}
/*
@@ -1017,25 +1028,7 @@ PrintPlanCacheLeakWarning(CachedPlan *plan)
void
ResourceOwnerEnlargeTupleDescs(ResourceOwner owner)
{
- int newmax;
-
- if (owner->ntupdescs < owner->maxtupdescs)
- return; /* nothing to do */
-
- if (owner->tupdescs == NULL)
- {
- newmax = 16;
- owner->tupdescs = (TupleDesc *)
- MemoryContextAlloc(TopMemoryContext, newmax * sizeof(TupleDesc));
- owner->maxtupdescs = newmax;
- }
- else
- {
- newmax = owner->maxtupdescs * 2;
- owner->tupdescs = (TupleDesc *)
- repalloc(owner->tupdescs, newmax * sizeof(TupleDesc));
- owner->maxtupdescs = newmax;
- }
+ ResourceArrayEnlarge(&(owner->tupdescarr));
}
/*
@@ -1046,9 +1039,7 @@ ResourceOwnerEnlargeTupleDescs(ResourceOwner owner)
void
ResourceOwnerRememberTupleDesc(ResourceOwner owner, TupleDesc tupdesc)
{
- Assert(owner->ntupdescs < owner->maxtupdescs);
- owner->tupdescs[owner->ntupdescs] = tupdesc;
- owner->ntupdescs++;
+ ResourceArrayAdd(&(owner->tupdescarr), (Datum) tupdesc);
}
/*
@@ -1057,25 +1048,12 @@ ResourceOwnerRememberTupleDesc(ResourceOwner owner, TupleDesc tupdesc)
void
ResourceOwnerForgetTupleDesc(ResourceOwner owner, TupleDesc tupdesc)
{
- TupleDesc *tupdescs = owner->tupdescs;
- int nt1 = owner->ntupdescs - 1;
- int i;
+ bool res = ResourceArrayRemove(&(owner->tupdescarr),
+ (Datum) tupdesc);
- for (i = nt1; i >= 0; i--)
- {
- if (tupdescs[i] == tupdesc)
- {
- while (i < nt1)
- {
- tupdescs[i] = tupdescs[i + 1];
- i++;
- }
- owner->ntupdescs = nt1;
- return;
- }
- }
- elog(ERROR, "tupdesc reference %p is not owned by resource owner %s",
- tupdesc, owner->name);
+ if (!res)
+ elog(ERROR, "tupdesc reference %p is not owned by resource owner %s",
+ tupdesc, owner->name);
}
/*
@@ -1099,25 +1077,7 @@ PrintTupleDescLeakWarning(TupleDesc tupdesc)
void
ResourceOwnerEnlargeSnapshots(ResourceOwner owner)
{
- int newmax;
-
- if (owner->nsnapshots < owner->maxsnapshots)
- return; /* nothing to do */
-
- if (owner->snapshots == NULL)
- {
- newmax = 16;
- owner->snapshots = (Snapshot *)
- MemoryContextAlloc(TopMemoryContext, newmax * sizeof(Snapshot));
- owner->maxsnapshots = newmax;
- }
- else
- {
- newmax = owner->maxsnapshots * 2;
- owner->snapshots = (Snapshot *)
- repalloc(owner->snapshots, newmax * sizeof(Snapshot));
- owner->maxsnapshots = newmax;
- }
+ ResourceArrayEnlarge(&(owner->snapshotarr));
}
/*
@@ -1128,9 +1088,7 @@ ResourceOwnerEnlargeSnapshots(ResourceOwner owner)
void
ResourceOwnerRememberSnapshot(ResourceOwner owner, Snapshot snapshot)
{
- Assert(owner->nsnapshots < owner->maxsnapshots);
- owner->snapshots[owner->nsnapshots] = snapshot;
- owner->nsnapshots++;
+ ResourceArrayAdd(&(owner->snapshotarr), (Datum) snapshot);
}
/*
@@ -1139,25 +1097,12 @@ ResourceOwnerRememberSnapshot(ResourceOwner owner, Snapshot snapshot)
void
ResourceOwnerForgetSnapshot(ResourceOwner owner, Snapshot snapshot)
{
- Snapshot *snapshots = owner->snapshots;
- int ns1 = owner->nsnapshots - 1;
- int i;
+ bool res = ResourceArrayRemove(&(owner->snapshotarr),
+ (Datum) snapshot);
- for (i = ns1; i >= 0; i--)
- {
- if (snapshots[i] == snapshot)
- {
- while (i < ns1)
- {
- snapshots[i] = snapshots[i + 1];
- i++;
- }
- owner->nsnapshots = ns1;
- return;
- }
- }
- elog(ERROR, "snapshot reference %p is not owned by resource owner %s",
- snapshot, owner->name);
+ if (!res)
+ elog(ERROR, "snapshot reference %p is not owned by resource owner %s",
+ snapshot, owner->name);
}
/*
@@ -1182,25 +1127,7 @@ PrintSnapshotLeakWarning(Snapshot snapshot)
void
ResourceOwnerEnlargeFiles(ResourceOwner owner)
{
- int newmax;
-
- if (owner->nfiles < owner->maxfiles)
- return; /* nothing to do */
-
- if (owner->files == NULL)
- {
- newmax = 16;
- owner->files = (File *)
- MemoryContextAlloc(TopMemoryContext, newmax * sizeof(File));
- owner->maxfiles = newmax;
- }
- else
- {
- newmax = owner->maxfiles * 2;
- owner->files = (File *)
- repalloc(owner->files, newmax * sizeof(File));
- owner->maxfiles = newmax;
- }
+ ResourceArrayEnlarge(&(owner->filearr));
}
/*
@@ -1211,9 +1138,7 @@ ResourceOwnerEnlargeFiles(ResourceOwner owner)
void
ResourceOwnerRememberFile(ResourceOwner owner, File file)
{
- Assert(owner->nfiles < owner->maxfiles);
- owner->files[owner->nfiles] = file;
- owner->nfiles++;
+ ResourceArrayAdd(&(owner->filearr), (Datum) file);
}
/*
@@ -1222,25 +1147,12 @@ ResourceOwnerRememberFile(ResourceOwner owner, File file)
void
ResourceOwnerForgetFile(ResourceOwner owner, File file)
{
- File *files = owner->files;
- int ns1 = owner->nfiles - 1;
- int i;
+ bool res = ResourceArrayRemove(&(owner->filearr),
+ (Datum) file);
- for (i = ns1; i >= 0; i--)
- {
- if (files[i] == file)
- {
- while (i < ns1)
- {
- files[i] = files[i + 1];
- i++;
- }
- owner->nfiles = ns1;
- return;
- }
- }
- elog(ERROR, "temporery file %d is not owned by resource owner %s",
- file, owner->name);
+ if (!res)
+ elog(ERROR, "temporary file %d is not owned by resource owner %s",
+ file, owner->name);
}
@@ -1265,26 +1177,7 @@ PrintFileLeakWarning(File file)
void
ResourceOwnerEnlargeDSMs(ResourceOwner owner)
{
- int newmax;
-
- if (owner->ndsms < owner->maxdsms)
- return; /* nothing to do */
-
- if (owner->dsms == NULL)
- {
- newmax = 16;
- owner->dsms = (dsm_segment **)
- MemoryContextAlloc(TopMemoryContext,
- newmax * sizeof(dsm_segment *));
- owner->maxdsms = newmax;
- }
- else
- {
- newmax = owner->maxdsms * 2;
- owner->dsms = (dsm_segment **)
- repalloc(owner->dsms, newmax * sizeof(dsm_segment *));
- owner->maxdsms = newmax;
- }
+ ResourceArrayEnlarge(&(owner->dsmarr));
}
/*
@@ -1295,9 +1188,7 @@ ResourceOwnerEnlargeDSMs(ResourceOwner owner)
void
ResourceOwnerRememberDSM(ResourceOwner owner, dsm_segment *seg)
{
- Assert(owner->ndsms < owner->maxdsms);
- owner->dsms[owner->ndsms] = seg;
- owner->ndsms++;
+ ResourceArrayAdd(&(owner->dsmarr), (Datum) seg);
}
/*
@@ -1306,26 +1197,12 @@ ResourceOwnerRememberDSM(ResourceOwner owner, dsm_segment *seg)
void
ResourceOwnerForgetDSM(ResourceOwner owner, dsm_segment *seg)
{
- dsm_segment **dsms = owner->dsms;
- int ns1 = owner->ndsms - 1;
- int i;
+ bool res = ResourceArrayRemove(&(owner->dsmarr),
+ (Datum) seg);
- for (i = ns1; i >= 0; i--)
- {
- if (dsms[i] == seg)
- {
- while (i < ns1)
- {
- dsms[i] = dsms[i + 1];
- i++;
- }
- owner->ndsms = ns1;
- return;
- }
- }
- elog(ERROR,
- "dynamic shared memory segment %u is not owned by resource owner %s",
- dsm_segment_handle(seg), owner->name);
+ if (!res)
+ elog(ERROR, "dynamic shared memory segment %u is not owned by resource"
+ " owner %s", dsm_segment_handle(seg), owner->name);
}
diff --git a/src/backend/access/hash/hashfunc.c b/src/backend/access/hash/hashfunc.c
index 9ee654e..5a00a03 100644
--- a/src/backend/access/hash/hashfunc.c
+++ b/src/backend/access/hash/hashfunc.c
@@ -297,6 +297,9 @@ hashvarlena(PG_FUNCTION_ARGS)
* of 2. There is no need to do mod a prime (mod is sooo slow!).
* If you need less than 32 bits, use a bitmask.
*
+ * This procedure never fails. Its important. Some code notably ResourceOwner
+ * relies on this.
+ *
* Note: we could easily change this function to return a 64-bit hash value
* by using the final values of both b and c. b is perhaps a little less
* well mixed than c, however.
diff --git a/src/backend/utils/resowner/resowner.c b/src/backend/utils/resowner/resowner.c
index 3330c8d..abed36c 100644
--- a/src/backend/utils/resowner/resowner.c
+++ b/src/backend/utils/resowner/resowner.c
@@ -37,29 +37,60 @@
* which should be called before corresponding ResourceOwnerRemember* calls
* (see below). Internally each type of resource is stored in separate
* ResourceArray.
+ *
+ * There are two major reasons for using ResourceArray instead of, say,
+ * regular C arrays.
+ *
+ * Firstly we would like to prevent code duplication. For instance
+ * ResourceArray provides generic Remember/Forget/Enlarge procedures, so
+ * corresponding ResourceOwner* procedures are just a typesafe wrappers for
+ * these procedures.
+ *
+ * Secondly ResourceArray must be more efficient than regular C array.
+ * Current implementation in general could be considered a hash table. It has
+ * O(1) complexity of both Remember and Forget procedures.
*/
typedef struct ResourceArray
{
Datum *itemsarr; /* buffer for storing values */
+ Datum invalidval; /* value that is considered invalid */
uint32 capacity; /* capacity of array */
uint32 nitems; /* how many items is stored in items array */
+ uint32 maxitems; /* precalculated RESARRAY_MAX_ITEMS(capacity) */
+ uint32 lastidx; /* index of last item returned by GetAny */
} ResourceArray;
/*
* This number is used as initial size of resource array. If given number of
* items is not enough, we double array size and reallocate memory.
+ *
+ * Should be power of two since we use (arrsize - 1) as mask for hash value.
+ *
*/
#define RESARRAY_INIT_SIZE 16
/*
+ * How many items could be stored in a resource array of given capacity. If
+ * this number is reached we need to resize an array to prevent hash collisions.
+ *
+ * This computation actually costs only two additions and one binary shift.
+ */
+#define RESARRAY_MAX_ITEMS(capacity) ((capacity)*3/4)
+
+/*
* Initialize ResourceArray
*/
static void
-ResourceArrayInit(ResourceArray * resarr)
+ResourceArrayInit(ResourceArray * resarr, Datum invalidval)
{
Assert(resarr->itemsarr == NULL);
Assert(resarr->capacity == 0);
Assert(resarr->nitems == 0);
+ Assert(resarr->maxitems == 0);
+ Assert(resarr->invalidval == 0);
+ Assert(resarr->lastidx == 0);
+
+ resarr->invalidval = invalidval;
}
/*
@@ -70,11 +101,24 @@ ResourceArrayInit(ResourceArray * resarr)
static void
ResourceArrayAdd(ResourceArray * resarr, Datum data)
{
+ Datum idx;
+ Datum mask = resarr->capacity - 1;
+
+ Assert(resarr->maxitems > resarr->nitems);
Assert(resarr->capacity > 0);
Assert(resarr->itemsarr != NULL);
- Assert(resarr->nitems < resarr->capacity);
+ Assert(data != resarr->invalidval);
+
+ idx = hash_any((void *) &data, sizeof(data)) & mask;
+
+ while (true)
+ {
+ if (resarr->itemsarr[idx] == resarr->invalidval)
+ break;
+ idx = (idx + 1) & mask;
+ }
- resarr->itemsarr[resarr->nitems] = data;
+ resarr->itemsarr[idx] = data;
resarr->nitems++;
}
@@ -86,24 +130,24 @@ ResourceArrayAdd(ResourceArray * resarr, Datum data)
static bool
ResourceArrayRemove(ResourceArray * resarr, Datum data)
{
- int i,
- j,
- lastidx;
+ uint32 i;
+ Datum idx;
+ Datum mask = resarr->capacity - 1;
Assert(resarr->capacity > 0);
Assert(resarr->itemsarr != NULL);
+ Assert(data != resarr->invalidval);
- lastidx = ((int) resarr->nitems) - 1;
-
- for (i = lastidx; i >= 0; i--)
+ idx = hash_any((void *) &data, sizeof(data)) & mask;
+ for (i = 0; i < resarr->capacity; i++)
{
- if (resarr->itemsarr[i] == data)
+ if (resarr->itemsarr[idx] == data)
{
- for (j = i; j < lastidx; j++)
- resarr->itemsarr[j] = resarr->itemsarr[j + 1];
+ resarr->itemsarr[idx] = resarr->invalidval;
resarr->nitems--;
return true;
}
+ idx = (idx + 1) & mask;
}
return false;
@@ -119,27 +163,33 @@ static void
ResourceArrayEnlarge(ResourceArray * resarr)
{
uint32 i,
- oldcap,
- oldnitems;
+ oldcap;
Datum *olditemsarr;
- if (resarr->nitems < resarr->capacity)
+ if (resarr->nitems < resarr->maxitems)
return; /* nothing to do */
olditemsarr = resarr->itemsarr;
oldcap = resarr->capacity;
- oldnitems = resarr->nitems;
resarr->capacity = oldcap > 0 ? oldcap * 2 : RESARRAY_INIT_SIZE;
resarr->itemsarr = (Datum *)
MemoryContextAlloc(TopMemoryContext,
resarr->capacity * sizeof(Datum));
+ resarr->maxitems = RESARRAY_MAX_ITEMS(resarr->capacity);
resarr->nitems = 0;
+ for (i = 0; i < resarr->capacity; i++)
+ resarr->itemsarr[i] = resarr->invalidval;
+
if (olditemsarr != NULL)
{
- for (i = 0; i < oldnitems; i++)
- ResourceArrayAdd(resarr, olditemsarr[i]);
+ while (oldcap > 0)
+ {
+ oldcap--;
+ if (olditemsarr[oldcap] != resarr->invalidval)
+ ResourceArrayAdd(resarr, olditemsarr[oldcap]);
+ }
pfree(olditemsarr);
}
}
@@ -152,12 +202,24 @@ ResourceArrayEnlarge(ResourceArray * resarr)
static bool
ResourceArrayGetAny(ResourceArray * resarr, Datum *out)
{
+ uint32 mask;
+
if (resarr->nitems == 0)
return false;
Assert(resarr->capacity > 0);
+ mask = resarr->capacity - 1;
+
+ for (;;)
+ {
+ resarr->lastidx = resarr->lastidx & mask;
+ if (resarr->itemsarr[resarr->lastidx] != resarr->invalidval)
+ break;
+
+ resarr->lastidx++;
+ }
- *out = resarr->itemsarr[resarr->nitems - 1];
+ *out = resarr->itemsarr[resarr->lastidx];
return true;
}
@@ -170,6 +232,7 @@ ResourceArrayFree(ResourceArray * resarr)
Assert(resarr->nitems == 0);
resarr->capacity = 0;
+ resarr->maxitems = 0;
if (!resarr->itemsarr)
return;
@@ -287,15 +350,15 @@ ResourceOwnerCreate(ResourceOwner parent, const char *name)
parent->firstchild = owner;
}
- ResourceArrayInit(&(owner->catrefarr));
- ResourceArrayInit(&(owner->catlistrefarr));
- ResourceArrayInit(&(owner->relrefarr));
- ResourceArrayInit(&(owner->planrefarr));
- ResourceArrayInit(&(owner->tupdescarr));
- ResourceArrayInit(&(owner->snapshotarr));
- ResourceArrayInit(&(owner->dsmarr));
- ResourceArrayInit(&(owner->bufferarr));
- ResourceArrayInit(&(owner->filearr));
+ ResourceArrayInit(&(owner->catrefarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->catlistrefarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->relrefarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->planrefarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->tupdescarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->snapshotarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->dsmarr), (Datum) (NULL));
+ ResourceArrayInit(&(owner->bufferarr), (Datum) (InvalidBuffer));
+ ResourceArrayInit(&(owner->filearr), (Datum) (-1));
return owner;
}
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