Datum
gtsquery_picksplit(PG_FUNCTION_ARGS)
{
GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
GIST_SPLITVEC *v = (GIST_SPLITVEC *) PG_GETARG_POINTER(1);
OffsetNumber maxoff = entryvec->n - 2;
OffsetNumber k,
j;
TSQuerySign *datum_l,
*datum_r;
int4 size_alpha,
size_beta;
int4 size_waste,
waste = -1;
int4 nbytes;
OffsetNumber seed_1 = 0,
seed_2 = 0;
OffsetNumber *left,
*right;
SPLITCOST *costvector;
nbytes = (maxoff + 2) * sizeof(OffsetNumber);
left = v->spl_left = (OffsetNumber *) palloc(nbytes);
right = v->spl_right = (OffsetNumber *) palloc(nbytes);
v->spl_nleft = v->spl_nright = 0;
for (k = FirstOffsetNumber; k < maxoff; k = OffsetNumberNext(k))
for (j = OffsetNumberNext(k); j <= maxoff; j = OffsetNumberNext(j))
{
size_waste = hemdist(*GETENTRY(entryvec, j), *GETENTRY(entryvec, k));
if (size_waste > waste)
{
waste = size_waste;
seed_1 = k;
seed_2 = j;
}
}
if (seed_1 == 0 || seed_2 == 0)
{
seed_1 = 1;
seed_2 = 2;
}
datum_l = (TSQuerySign *) palloc(sizeof(TSQuerySign));
*datum_l = *GETENTRY(entryvec, seed_1);
datum_r = (TSQuerySign *) palloc(sizeof(TSQuerySign));
*datum_r = *GETENTRY(entryvec, seed_2);
maxoff = OffsetNumberNext(maxoff);
costvector = (SPLITCOST *) palloc(sizeof(SPLITCOST) * maxoff);
for (j = FirstOffsetNumber; j <= maxoff; j = OffsetNumberNext(j))
{
costvector[j - 1].pos = j;
size_alpha = hemdist(*GETENTRY(entryvec, seed_1), *GETENTRY(entryvec, j));
size_beta = hemdist(*GETENTRY(entryvec, seed_2), *GETENTRY(entryvec, j));
costvector[j - 1].cost = abs(size_alpha - size_beta);
}
qsort((void *) costvector, maxoff, sizeof(SPLITCOST), comparecost);
for (k = 0; k < maxoff; k++)
{
j = costvector[k].pos;
if (j == seed_1)
{
*left++ = j;
v->spl_nleft++;
continue;
}
else if (j == seed_2)
{
*right++ = j;
v->spl_nright++;
continue;
}
size_alpha = hemdist(*datum_l, *GETENTRY(entryvec, j));
size_beta = hemdist(*datum_r, *GETENTRY(entryvec, j));
if (size_alpha < size_beta + WISH_F(v->spl_nleft, v->spl_nright, 0.05))
{
*datum_l |= *GETENTRY(entryvec, j);
*left++ = j;
v->spl_nleft++;
}
else
{
*datum_r |= *GETENTRY(entryvec, j);
*right++ = j;
v->spl_nright++;
}
}
*right = *left = FirstOffsetNumber;
v->spl_ldatum = PointerGetDatum(datum_l);
v->spl_rdatum = PointerGetDatum(datum_r);
PG_RETURN_POINTER(v);
}
/*
** The GiST PickSplit method for _intments
** We use Guttman's poly time split algorithm
*/
Datum
g_int_picksplit(PG_FUNCTION_ARGS)
{
GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
GIST_SPLITVEC *v = (GIST_SPLITVEC *) PG_GETARG_POINTER(1);
OffsetNumber i,
j;
ArrayType *datum_alpha,
*datum_beta;
ArrayType *datum_l,
*datum_r;
ArrayType *union_d,
*union_dl,
*union_dr;
ArrayType *inter_d;
bool firsttime;
float size_alpha,
size_beta,
size_union,
size_inter;
float size_waste,
waste;
float size_l,
size_r;
int nbytes;
OffsetNumber seed_1 = 0,
seed_2 = 0;
OffsetNumber *left,
*right;
OffsetNumber maxoff;
SPLITCOST *costvector;
#ifdef GIST_DEBUG
elog(DEBUG3, "--------picksplit %d", entryvec->n);
#endif
maxoff = entryvec->n - 2;
nbytes = (maxoff + 2) * sizeof(OffsetNumber);
v->spl_left = (OffsetNumber *) palloc(nbytes);
v->spl_right = (OffsetNumber *) palloc(nbytes);
firsttime = true;
waste = 0.0;
for (i = FirstOffsetNumber; i < maxoff; i = OffsetNumberNext(i))
{
datum_alpha = GETENTRY(entryvec, i);
for (j = OffsetNumberNext(i); j <= maxoff; j = OffsetNumberNext(j))
{
datum_beta = GETENTRY(entryvec, j);
/* compute the wasted space by unioning these guys */
/* size_waste = size_union - size_inter; */
union_d = inner_int_union(datum_alpha, datum_beta);
rt__int_size(union_d, &size_union);
inter_d = inner_int_inter(datum_alpha, datum_beta);
rt__int_size(inter_d, &size_inter);
size_waste = size_union - size_inter;
pfree(union_d);
if (inter_d != (ArrayType *) NULL)
pfree(inter_d);
/*
* are these a more promising split that what we've already seen?
*/
if (size_waste > waste || firsttime)
{
waste = size_waste;
seed_1 = i;
seed_2 = j;
firsttime = false;
}
}
}
left = v->spl_left;
v->spl_nleft = 0;
right = v->spl_right;
v->spl_nright = 0;
if (seed_1 == 0 || seed_2 == 0)
{
seed_1 = 1;
seed_2 = 2;
}
datum_alpha = GETENTRY(entryvec, seed_1);
datum_l = copy_intArrayType(datum_alpha);
rt__int_size(datum_l, &size_l);
datum_beta = GETENTRY(entryvec, seed_2);
datum_r = copy_intArrayType(datum_beta);
rt__int_size(datum_r, &size_r);
maxoff = OffsetNumberNext(maxoff);
/*
* sort entries
*/
costvector = (SPLITCOST *) palloc(sizeof(SPLITCOST) * maxoff);
for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i))
{
costvector[i - 1].pos = i;
datum_alpha = GETENTRY(entryvec, i);
union_d = inner_int_union(datum_l, datum_alpha);
rt__int_size(union_d, &size_alpha);
pfree(union_d);
union_d = inner_int_union(datum_r, datum_alpha);
rt__int_size(union_d, &size_beta);
pfree(union_d);
costvector[i - 1].cost = Abs((size_alpha - size_l) - (size_beta - size_r));
}
qsort((void *) costvector, maxoff, sizeof(SPLITCOST), comparecost);
/*
* Now split up the regions between the two seeds. An important property
* of this split algorithm is that the split vector v has the indices of
* items to be split in order in its left and right vectors. We exploit
* this property by doing a merge in the code that actually splits the
* page.
*
* For efficiency, we also place the new index tuple in this loop. This is
* handled at the very end, when we have placed all the existing tuples
* and i == maxoff + 1.
*/
for (j = 0; j < maxoff; j++)
{
i = costvector[j].pos;
/*
* If we've already decided where to place this item, just put it on
* the right list. Otherwise, we need to figure out which page needs
* the least enlargement in order to store the item.
*/
if (i == seed_1)
{
*left++ = i;
v->spl_nleft++;
continue;
}
else if (i == seed_2)
{
*right++ = i;
v->spl_nright++;
continue;
}
/* okay, which page needs least enlargement? */
datum_alpha = GETENTRY(entryvec, i);
union_dl = inner_int_union(datum_l, datum_alpha);
union_dr = inner_int_union(datum_r, datum_alpha);
rt__int_size(union_dl, &size_alpha);
rt__int_size(union_dr, &size_beta);
/* pick which page to add it to */
if (size_alpha - size_l < size_beta - size_r + WISH_F(v->spl_nleft, v->spl_nright, 0.01))
{
if (datum_l)
pfree(datum_l);
if (union_dr)
pfree(union_dr);
datum_l = union_dl;
size_l = size_alpha;
*left++ = i;
v->spl_nleft++;
}
else
{
if (datum_r)
pfree(datum_r);
if (union_dl)
pfree(union_dl);
datum_r = union_dr;
size_r = size_beta;
*right++ = i;
v->spl_nright++;
}
}
pfree(costvector);
*right = *left = FirstOffsetNumber;
v->spl_ldatum = PointerGetDatum(datum_l);
v->spl_rdatum = PointerGetDatum(datum_r);
PG_RETURN_POINTER(v);
}
Datum
gmol_picksplit(PG_FUNCTION_ARGS)
{
GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
GIST_SPLITVEC *v = (GIST_SPLITVEC *) PG_GETARG_POINTER(1);
OffsetNumber k, j;
bytea *datum_l, *datum_r;
int32 size_alpha, size_beta;
int32 size_waste, waste = -1;
int32 nbytes;
OffsetNumber seed_1 = 0, seed_2 = 0;
OffsetNumber *left, *right;
OffsetNumber maxoff;
int i, signlen = 0;
SPLITCOST *costvector;
maxoff = entryvec->n - 1;
nbytes = (maxoff + 2) * sizeof(OffsetNumber);
v->spl_left = (OffsetNumber *) palloc(nbytes);
v->spl_right = (OffsetNumber *) palloc(nbytes);
for (k = FirstOffsetNumber; k < maxoff; k = OffsetNumberNext(k)) {
if (signlen == 0) {
signlen = SIGLEN(GETENTRY(entryvec, k));
}
for (j = OffsetNumberNext(k); j <= maxoff; j = OffsetNumberNext(j)) {
size_waste = hemdist(GETENTRY(entryvec, j), GETENTRY(entryvec, k));
if (size_waste > waste) {
waste = size_waste;
seed_1 = k;
seed_2 = j;
}
}
}
if (signlen == 0) {
signlen = SIGLEN(GETENTRY(entryvec, maxoff));
}
left = v->spl_left;
v->spl_nleft = 0;
right = v->spl_right;
v->spl_nright = 0;
if (signlen == 0 || waste == 0) {
/* all entries a alltrue or all the same */
for (k = FirstOffsetNumber; k <= maxoff; k = OffsetNumberNext(k)) {
if (k <= (maxoff - FirstOffsetNumber + 1) / 2) {
v->spl_left[v->spl_nleft] = k;
v->spl_nleft++;
}
else {
v->spl_right[v->spl_nright] = k;
v->spl_nright++;
}
}
signlen = VARSIZE(GETENTRY(entryvec, FirstOffsetNumber));
datum_l = palloc(signlen);
memcpy(datum_l, GETENTRY(entryvec, FirstOffsetNumber), signlen);
v->spl_ldatum = PointerGetDatum(datum_l);
datum_r = palloc(signlen);
memcpy(datum_r, GETENTRY(entryvec, FirstOffsetNumber), signlen);
v->spl_rdatum = PointerGetDatum(datum_r);
Assert( v->spl_nleft + v->spl_nright == maxoff );
PG_RETURN_POINTER(v);
}
if (seed_1 == 0 || seed_2 == 0) {
seed_1 = 1;
seed_2 = 2;
}
/* form initial .. */
if (ISALLTRUE(GETENTRY(entryvec, seed_1))) {
datum_l = palloc(VARHDRSZ);
SET_VARSIZE(datum_l, VARHDRSZ);
}
else {
datum_l = palloc(signlen + VARHDRSZ);
memcpy(datum_l , GETENTRY(entryvec, seed_1) , signlen + VARHDRSZ);
}
if (ISALLTRUE(GETENTRY(entryvec, seed_2))) {
datum_r = palloc(VARHDRSZ);
SET_VARSIZE(datum_r, VARHDRSZ);
}
else {
datum_r = palloc(signlen + VARHDRSZ);
memcpy(datum_r , GETENTRY(entryvec, seed_2) , signlen + VARHDRSZ);
}
/* sort before ... */
costvector = (SPLITCOST *) palloc(sizeof(SPLITCOST) * maxoff);
for (j = FirstOffsetNumber; j <= maxoff; j = OffsetNumberNext(j)) {
costvector[j - 1].pos = j;
size_alpha = hemdist(datum_l, GETENTRY(entryvec, j));
size_beta = hemdist(datum_r, GETENTRY(entryvec, j));
costvector[j - 1].cost = Abs(size_alpha - size_beta);
}
qsort((void *) costvector, maxoff, sizeof(SPLITCOST), comparecost);
for (k = 0; k < maxoff; k++) {
j = costvector[k].pos;
if (j == seed_1) {
*left++ = j;
v->spl_nleft++;
continue;
}
else if (j == seed_2) {
*right++ = j;
v->spl_nright++;
continue;
}
size_alpha = hemdist(GETENTRY(entryvec, j), datum_l);
size_beta = hemdist(GETENTRY(entryvec, j), datum_r);
if (size_alpha < size_beta + WISH_F(v->spl_nleft, v->spl_nright, 0.1)) {
if (!ISALLTRUE(datum_l)) {
if (ISALLTRUE(GETENTRY(entryvec, j))) {
datum_l = palloc(VARHDRSZ);
SET_VARSIZE(datum_l, VARHDRSZ);
}
else {
unsigned char
*as = (unsigned char *)VARDATA(datum_l),
*bs = (unsigned char *)VARDATA(GETENTRY(entryvec, j));
for (i=0;i<signlen;i++) {
as[i] |= bs[i];
}
}
}
*left++ = j;
v->spl_nleft++;
}
else {
if (!ISALLTRUE(datum_r)) {
if (ISALLTRUE(GETENTRY(entryvec, j))) {
datum_r = palloc(VARHDRSZ);
SET_VARSIZE(datum_r, VARHDRSZ);
}
else {
unsigned char
*as = (unsigned char *)VARDATA(datum_r),
*bs = (unsigned char *)VARDATA(GETENTRY(entryvec, j));
for (i=0;i<signlen;i++) {
as[i] |= bs[i];
}
}
}
*right++ = j;
v->spl_nright++;
}
}
*right = *left = FirstOffsetNumber;
v->spl_ldatum = PointerGetDatum(datum_l);
v->spl_rdatum = PointerGetDatum(datum_r);
Assert( v->spl_nleft + v->spl_nright == maxoff );
PG_RETURN_POINTER(v);
}