From 027e1daa105b3ffe8c1061d9aca0fe22714518b9 Mon Sep 17 00:00:00 2001 From: Howard Chu Date: Sat, 27 Aug 2011 16:53:58 -0700 Subject: [PATCH] Fix mdb_split, tweak split_indx if space is tight --- libraries/libmdb/mdb.c | 53 +++++++++++++++++++++++++++++++++++++----- 1 file changed, 47 insertions(+), 6 deletions(-) diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c index 8937a8e9fd..d1efdd1b24 100644 --- a/libraries/libmdb/mdb.c +++ b/libraries/libmdb/mdb.c @@ -2502,10 +2502,10 @@ mdb_add_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp, indx_t indx, assert(mp->mp_upper >= mp->mp_lower); - DPRINTF("add node [%s] to %s page %lu at index %i, key size %zu", - key ? DKEY(key) : NULL, + DPRINTF("add to %s page %lu index %i, data size %zu key size %zu [%s]", IS_LEAF(mp) ? "leaf" : "branch", - mp->mp_pgno, indx, key ? key->mv_size : 0); + mp->mp_pgno, indx, data ? data->mv_size : 0, + key ? key->mv_size : 0, key ? DKEY(key) : NULL); if (IS_LEAF2(mp)) { /* Move higher keys up one slot. */ @@ -3213,7 +3213,7 @@ mdb_split(MDB_txn *txn, MDB_dbi dbi, MDB_page **mpp, unsigned int *newindxp, int rc = MDB_SUCCESS, ins_new = 0; indx_t newindx; pgno_t pgno = 0; - unsigned int i, j, split_indx; + unsigned int i, j, split_indx, nkeys, pmax; MDB_node *node; MDB_val sepkey, rkey, rdata; MDB_page *copy; @@ -3255,12 +3255,13 @@ mdb_split(MDB_txn *txn, MDB_dbi dbi, MDB_page **mpp, unsigned int *newindxp, rdp->h.md_pi = mdp->h.md_pi + 1; DPRINTF("new right sibling: page %lu", rdp->p.mp_pgno); - split_indx = NUMKEYS(&mdp->p) / 2 + 1; + nkeys = NUMKEYS(&mdp->p); + split_indx = nkeys / 2 + 1; if (IS_LEAF2(&rdp->p)) { char *split, *ins; int x; - unsigned int nkeys = NUMKEYS(&mdp->p), lsize, rsize, ksize; + unsigned int lsize, rsize, ksize; /* Move half of the keys to the right sibling */ copy = NULL; x = *newindxp - split_indx; @@ -3307,6 +3308,46 @@ mdb_split(MDB_txn *txn, MDB_dbi dbi, MDB_page **mpp, unsigned int *newindxp, memset(&mdp->p.mp_ptrs, 0, txn->mt_env->me_psize - PAGEHDRSZ); mdp->p.mp_lower = PAGEHDRSZ; mdp->p.mp_upper = txn->mt_env->me_psize; + /* For leaf pages, check the split point based on what + * fits where, since otherwise add_node can fail. + */ + if (IS_LEAF(&mdp->p)) { + unsigned int psize, nsize; + /* Maximum free space in an empty page */ + pmax = txn->mt_env->me_psize - PAGEHDRSZ; + nsize = mdb_leaf_size(txn->mt_env, newkey, newdata); + if (newindx <= split_indx) { +split1: + psize = nsize; + for (i=0; ip, i); + psize += NODESIZE + NODEKSZ(node); + if (F_ISSET(node->mn_flags, F_BIGDATA)) + psize += sizeof(pgno_t); + else + psize += NODEDSZ(node); + if (psize > pmax) { + split_indx--; + goto split1; + } + } + } else { +split2: + psize = nsize; + for (i=split_indx; ip, i); + psize += NODESIZE + NODEKSZ(node); + if (F_ISSET(node->mn_flags, F_BIGDATA)) + psize += sizeof(pgno_t); + else + psize += NODEDSZ(node); + if (psize > pmax) { + split_indx++; + goto split2; + } + } + } + } /* First find the separating key between the split pages. */ -- 2.39.5