diff options
Diffstat (limited to 'src/btree/row_srch.c')
| -rw-r--r-- | src/btree/row_srch.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/src/btree/row_srch.c b/src/btree/row_srch.c index 9803b924355..d83d3253c44 100644 --- a/src/btree/row_srch.c +++ b/src/btree/row_srch.c @@ -471,6 +471,7 @@ __wt_row_random(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt) WT_PAGE *page; WT_PAGE_INDEX *pindex; WT_REF *current, *descent; + uint32_t cnt; btree = S2BT(session); @@ -528,18 +529,22 @@ restart: /* * If the tree is new (and not empty), it might have a large insert - * list, pick the key in the middle of that insert list. + * list. Count how many records are in the list. */ F_SET(cbt, WT_CBT_SEARCH_SMALLEST); if ((cbt->ins_head = WT_ROW_INSERT_SMALLEST(page)) == NULL) WT_ERR(WT_NOTFOUND); - for (p = t = WT_SKIP_FIRST(cbt->ins_head);;) { + for (cnt = 1, p = WT_SKIP_FIRST(cbt->ins_head);; ++cnt) if ((p = WT_SKIP_NEXT(p)) == NULL) break; - if ((p = WT_SKIP_NEXT(p)) == NULL) + + /* + * Select a random number from 0 to (N - 1), return that record. + */ + cnt = __wt_random(&session->rnd) % cnt; + for (p = t = WT_SKIP_FIRST(cbt->ins_head);; t = p) + if (cnt-- == 0 || (p = WT_SKIP_NEXT(p)) == NULL) break; - t = WT_SKIP_NEXT(t); - } cbt->ref = current; cbt->compare = 0; cbt->ins = t; |