mirror/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-01-22 23:04:20 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

Addresses #825

Browse source 
On inserts, we will rebalance at most 1 subtree.

git-svn-id: file:///svn/tokudb@3942 c7de825b-a66e-492c-adef-691d508d4ae1
This commit is contained in:
Yoni Fogel 2008-05-13 19:24:07 +00:00
parent ae2a2766ff
commit b2d86c0bde
1 changed files with 32 additions and 17 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

49
newbrt/omt.c
View file

@ -212,22 +212,30 @@ static inline void rebuild_subtree_from_idxs(OMT omt, node_idx *n_idxp, node_idx
}
}
static inline void maybe_rebalance(OMT omt, node_idx *n_idxp) {
static inline void rebalance(OMT omt, node_idx *n_idxp) {
node_idx idx = *n_idxp;
if (idx==NODE_NULL) return;
OMT_NODE n = omt->nodes+idx;
// one of the 1's is for the root.
// the other is to take ceil(n/2)
if (((1+nweight(omt, n->left)) < (1+1+nweight(omt, n->right))/2)
||
((1+nweight(omt, n->right)) < (1+1+nweight(omt, n->left))/2)) {
// Must rebalance the subtree.
fill_array_with_subtree_idxs(omt, omt->tmparray, idx);
rebuild_subtree_from_idxs(omt, n_idxp, omt->tmparray, n->weight);
}
OMT_NODE n = omt->nodes+idx;
fill_array_with_subtree_idxs(omt, omt->tmparray, idx);
rebuild_subtree_from_idxs(omt, n_idxp, omt->tmparray, n->weight);
}
static inline void insert_internal(OMT omt, node_idx *n_idxp, OMTVALUE value, u_int32_t index) {
static inline BOOL will_need_rebalance(OMT omt, node_idx n_idx, int leftmod, int rightmod) {
if (n_idx==NODE_NULL) return FALSE;
OMT_NODE n = omt->nodes+n_idx;
// one of the 1's is for the root.
// the other is to take ceil(n/2)
u_int32_t weight_left = nweight(omt, n->left) + leftmod;
u_int32_t weight_right = nweight(omt, n->right) + rightmod;
return ((1+weight_left < (1+1+weight_right)/2)
||
(1+weight_right < (1+1+weight_left)/2));
}
static inline void maybe_rebalance(OMT omt, node_idx *n_idxp) {
if (will_need_rebalance(omt, *n_idxp, 0, 0)) rebalance(omt, n_idxp);
}
static inline void insert_internal(OMT omt, node_idx *n_idxp, OMTVALUE value, u_int32_t index, node_idx **rebalance_idx) {
if (*n_idxp==NODE_NULL) {
assert(index==0);
node_idx newidx = omt_node_malloc(omt);
@ -241,13 +249,18 @@ static inline void insert_internal(OMT omt, node_idx *n_idxp, OMTVALUE value, u_
node_idx idx = *n_idxp;
OMT_NODE n = omt->nodes+idx;
if (index <= nweight(omt, n->left)) {
insert_internal(omt, &n->left, value, index);
if (*rebalance_idx==NULL && will_need_rebalance(omt, idx, 1, 0)) {
*rebalance_idx = n_idxp;
}
insert_internal(omt, &n->left, value, index, rebalance_idx);
} else {
if (*rebalance_idx==NULL && will_need_rebalance(omt, idx, 0, 1)) {
*rebalance_idx = n_idxp;
}
u_int32_t sub_index = index-nweight(omt, n->left)-1;
insert_internal(omt, &n->right, value, sub_index);
insert_internal(omt, &n->right, value, sub_index, rebalance_idx);
}
n->weight++;
maybe_rebalance(omt, n_idxp);
}
}
@ -255,7 +268,9 @@ int toku_omt_insert_at(OMT omt, OMTVALUE value, u_int32_t index) {
int r;
if (index>nweight(omt, omt->root)) return ERANGE;
if ((r=maybe_resize_and_rebuild(omt, 1+nweight(omt, omt->root), MAYBE_REBUILD))) return r;
insert_internal(omt, &omt->root, value, index);
node_idx* rebalance_idx = NULL;
insert_internal(omt, &omt->root, value, index, &rebalance_idx);
if (rebalance_idx) rebalance(omt, rebalance_idx);
return 0;
}