diff options
Diffstat (limited to 'db2/hash/hash.c')
| -rw-r--r-- | db2/hash/hash.c | 135 |
1 files changed, 83 insertions, 52 deletions
diff --git a/db2/hash/hash.c b/db2/hash/hash.c index d986e08087..c08495378e 100644 --- a/db2/hash/hash.c +++ b/db2/hash/hash.c @@ -47,7 +47,7 @@ #include "config.h" #ifndef lint -static const char sccsid[] = "@(#)hash.c 10.27 (Sleepycat) 9/15/97"; +static const char sccsid[] = "@(#)hash.c 10.33 (Sleepycat) 11/2/97"; #endif /* not lint */ #ifndef NO_SYSTEM_INCLUDES @@ -79,7 +79,7 @@ static int __ham_cursor __P((DB *, DB_TXN *, DBC **)); static int __ham_delete __P((DB *, DB_TXN *, DBT *, int)); static int __ham_dup_return __P((HTAB *, HASH_CURSOR *, DBT *, int)); static int __ham_get __P((DB *, DB_TXN *, DBT *, DBT *, int)); -static void __ham_init_htab __P((HTAB *)); +static void __ham_init_htab __P((HTAB *, u_int)); static int __ham_lookup __P((HTAB *, HASH_CURSOR *, const DBT *, u_int32_t, db_lockmode_t)); static int __ham_overwrite __P((HTAB *, HASH_CURSOR *, DBT *)); @@ -106,7 +106,7 @@ __ham_open(dbp, dbinfo) dbenv = dbp->dbenv; - if ((hashp = (HTAB *)calloc(1, sizeof(HTAB))) == NULL) + if ((hashp = (HTAB *)__db_calloc(1, sizeof(HTAB))) == NULL) return (ENOMEM); hashp->dbp = dbp; @@ -175,10 +175,9 @@ __ham_open(dbp, dbinfo) goto out; } - hashp->hdr->nelem = dbinfo != NULL ? dbinfo->h_nelem : 0; hashp->hdr->ffactor = dbinfo != NULL && dbinfo->h_ffactor ? dbinfo->h_ffactor : 0; - __ham_init_htab(hashp); + __ham_init_htab(hashp, dbinfo != NULL ? dbinfo->h_nelem : 0); if (F_ISSET(dbp, DB_AM_DUP)) F_SET(hashp->hdr, DB_HASH_DUP); if ((ret = __ham_dirty_page(hashp, (PAGE *)hashp->hdr)) != 0) @@ -190,7 +189,7 @@ __ham_open(dbp, dbinfo) TAILQ_INSERT_TAIL(&dbp->curs_queue, curs, links); /* Allocate memory for our split buffer. */ - if ((hashp->split_buf = (PAGE *)malloc(dbp->pgsize)) == NULL) { + if ((hashp->split_buf = (PAGE *)__db_malloc(dbp->pgsize)) == NULL) { ret = ENOMEM; goto out; } @@ -265,13 +264,13 @@ __ham_close(dbp) * Returns 0 on No Error */ static void -__ham_init_htab(hashp) +__ham_init_htab(hashp, nelem) HTAB *hashp; + u_int nelem; { - u_int32_t nelem; int32_t l2, nbuckets; - nelem = hashp->hdr->nelem; + hashp->hdr->nelem = 0; hashp->hdr->pagesize = hashp->dbp->pgsize; ZERO_LSN(hashp->hdr->lsn); hashp->hdr->magic = DB_HASHMAGIC; @@ -502,11 +501,11 @@ __ham_c_init(dbp, txnid, dbcp) DBC *db_curs; HASH_CURSOR *new_curs; - if ((db_curs = (DBC *)calloc(sizeof(DBC), 1)) == NULL) + if ((db_curs = (DBC *)__db_calloc(sizeof(DBC), 1)) == NULL) return (ENOMEM); if ((new_curs = - (HASH_CURSOR *)calloc(sizeof(struct cursor_t), 1)) == NULL) { + (HASH_CURSOR *)__db_calloc(sizeof(struct cursor_t), 1)) == NULL) { FREE(db_curs, sizeof(DBC)); return (ENOMEM); } @@ -555,7 +554,7 @@ __ham_delete(dbp, txn, key, flags) hashp->hash_accesses++; if ((ret = __ham_lookup(hashp, hcp, key, 0, DB_LOCK_WRITE)) == 0) if (F_ISSET(hcp, H_OK)) - ret = __ham_del_pair(hashp, hcp); + ret = __ham_del_pair(hashp, hcp, 1); else ret = DB_NOTFOUND; @@ -669,30 +668,41 @@ __ham_c_del(cursor, flags) if ((ret = __ham_get_cpage(hashp, hcp, DB_LOCK_WRITE)) != 0) goto out; if (F_ISSET(hcp, H_ISDUP) && hcp->dpgno != PGNO_INVALID) { - ppgno = PREV_PGNO(hcp->dpagep); - - /* Remove item from duplicate page. */ - chg_pgno = hcp->dpgno; - if ((ret = __db_drem(hashp->dbp, - &hcp->dpagep, hcp->dndx, __ham_del_page)) != 0) - goto out; - /* + * We are about to remove a duplicate from offpage. + * * There are 4 cases. - * 1. We removed an item on a page, but nothing else changed. - * 2. We removed the last item on a page, but there is a + * 1. We will remove an item on a page, but there are more + * items on that page. + * 2. We will remove the last item on a page, but there is a * following page of duplicates. - * 3. We removed the last item on a page, this page was the + * 3. We will remove the last item on a page, this page was the * last page in a duplicate set, but there were dups before * it. - * 4. We removed the last item on a page, removing the last + * 4. We will remove the last item on a page, removing the last * duplicate. * In case 1 hcp->dpagep is unchanged. * In case 2 hcp->dpagep comes back pointing to the next dup * page. * In case 3 hcp->dpagep comes back NULL. * In case 4 hcp->dpagep comes back NULL. + * + * Case 4 results in deleting the pair off the master page. + * The normal code for doing this knows how to delete the + * duplicates, so we will handle this case in the normal code. */ + ppgno = PREV_PGNO(hcp->dpagep); + if (ppgno == PGNO_INVALID && + NEXT_PGNO(hcp->dpagep) == PGNO_INVALID && + NUM_ENT(hcp->dpagep) == 1) + goto normal; + + /* Remove item from duplicate page. */ + chg_pgno = hcp->dpgno; + if ((ret = __db_drem(hashp->dbp, + &hcp->dpagep, hcp->dndx, __ham_del_page)) != 0) + goto out; + if (hcp->dpagep == NULL) { if (ppgno != PGNO_INVALID) { /* Case 3 */ hcp->dpgno = ppgno; @@ -702,7 +712,7 @@ __ham_c_del(cursor, flags) hcp->dndx = NUM_ENT(hcp->dpagep); F_SET(hcp, H_DELETED); } else { /* Case 4 */ - ret = __ham_del_pair(hashp, hcp); + ret = __ham_del_pair(hashp, hcp, 1); hcp->dpgno = PGNO_INVALID; /* * Delpair updated the cursor queue, so we @@ -718,14 +728,14 @@ __ham_c_del(cursor, flags) H_DATAINDEX(hcp->bndx))), &hcp->dpgno, sizeof(db_pgno_t)); F_SET(hcp, H_DELETED); - } else /* Case 1 */ + } else /* Case 1 */ F_SET(hcp, H_DELETED); if (chg_pgno != PGNO_INVALID) __ham_c_update(hashp, hcp, chg_pgno, 0, 0, 1); } else if (F_ISSET(hcp, H_ISDUP)) { /* on page */ if (hcp->dup_off == 0 && DUP_SIZE(hcp->dup_len) == LEN_HDATA(hcp->pagep, hashp->hdr->pagesize, hcp->bndx)) - ret = __ham_del_pair(hashp, hcp); + ret = __ham_del_pair(hashp, hcp, 1); else { DBT repldbt; @@ -736,14 +746,14 @@ __ham_c_del(cursor, flags) repldbt.size = 0; ret = __ham_replpair(hashp, hcp, &repldbt, 0); hcp->dup_tlen -= DUP_SIZE(hcp->dup_len); + F_SET(hcp, H_DELETED); __ham_c_update(hashp, hcp, hcp->pgno, DUP_SIZE(hcp->dup_len), 0, 1); - F_SET(hcp, H_DELETED); } } else /* Not a duplicate */ - ret = __ham_del_pair(hashp, hcp); +normal: ret = __ham_del_pair(hashp, hcp, 1); out: if ((t_ret = __ham_item_done(hashp, hcp, ret == 0)) != 0 && ret == 0) t_ret = ret; @@ -975,8 +985,8 @@ int __ham_expand_table(hashp) HTAB *hashp; { - u_int32_t old_bucket, new_bucket; - u_int32_t spare_ndx; + DB_LSN new_lsn; + u_int32_t old_bucket, new_bucket, spare_ndx; int ret; ret = 0; @@ -984,9 +994,30 @@ __ham_expand_table(hashp) if (ret) return (ret); - if (DB_LOGGING(hashp->dbp)) { - DB_LSN new_lsn; + /* + * If the split point is about to increase, make sure that we + * have enough extra pages. The calculation here is weird. + * We'd like to do this after we've upped max_bucket, but it's + * too late then because we've logged the meta-data split. What + * we'll do between then and now is increment max bucket and then + * see what the log of one greater than that is; here we have to + * look at the log of max + 2. VERY NASTY STUFF. + */ + if (__db_log2(hashp->hdr->max_bucket + 2) > hashp->hdr->ovfl_point) { + /* + * We are about to shift the split point. Make sure that + * if the next doubling is going to be big (more than 8 + * pages), we have some extra pages around. + */ + if (hashp->hdr->max_bucket + 1 >= 8 && + hashp->hdr->spares[hashp->hdr->ovfl_point] < + hashp->hdr->spares[hashp->hdr->ovfl_point - 1] + + hashp->hdr->ovfl_point + 1) + __ham_init_ovflpages(hashp); + } + /* Now we can log the meta-data split. */ + if (DB_LOGGING(hashp->dbp)) { if ((ret = __ham_splitmeta_log(hashp->dbp->dbenv->lg_info, (DB_TXN *)hashp->dbp->txn, &new_lsn, 0, hashp->dbp->log_fileid, @@ -1003,22 +1034,11 @@ __ham_expand_table(hashp) old_bucket = (hashp->hdr->max_bucket & hashp->hdr->low_mask); /* - * If the split point is increasing (hdr.max_bucket's log base 2 - * increases), max sure that we have enough extra pages, then - * copy the current contents of the spare split bucket to the - * next bucket. + * If the split point is increasing, copy the current contents + * of the spare split bucket to the next bucket. */ spare_ndx = __db_log2(hashp->hdr->max_bucket + 1); if (spare_ndx > hashp->hdr->ovfl_point) { - /* - * We are about to shift the split point. Make sure that - * if the next doubling is going to be big (more than 8 - * pages), we have some extra pages around. - */ - if (hashp->hdr->spares[hashp->hdr->ovfl_point] == 0 && - new_bucket >= 8) - __ham_init_ovflpages(hashp); - hashp->hdr->spares[spare_ndx] = hashp->hdr->spares[hashp->hdr->ovfl_point]; hashp->hdr->ovfl_point = spare_ndx; @@ -1306,7 +1326,7 @@ __ham_init_dbt(dbt, size, bufp, sizep) memset(dbt, 0, sizeof(*dbt)); if (*sizep < size) { if ((*bufp = (void *)(*bufp == NULL ? - malloc(size) : realloc(*bufp, size))) == NULL) { + __db_malloc(size) : __db_realloc(*bufp, size))) == NULL) { *sizep = 0; return (ENOMEM); } @@ -1352,9 +1372,20 @@ __ham_c_update(hashp, hcp, chg_pgno, len, add, dup) if (!dup && add) return; - page_deleted = chg_pgno != PGNO_INVALID && - ((!dup && chg_pgno != hcp->pgno) || - (dup && chg_pgno != hcp->dpgno)); + /* + * Determine if a page was deleted. If this is a regular update + * (i.e., not dup) then the deleted page's number will be that in + * chg_pgno, and the pgno in the cursor will be different. If this + * was an onpage-duplicate, then the same conditions apply. If this + * was an off-page duplicate, then we need to verify if hcp->dpgno + * is the same (no delete) or different (delete) than chg_pgno. + */ + if (!dup || hcp->dpgno == PGNO_INVALID) + page_deleted = + chg_pgno != PGNO_INVALID && chg_pgno != hcp->pgno; + else + page_deleted = + chg_pgno != PGNO_INVALID && chg_pgno != hcp->dpgno; hp = hcp->db_cursor->dbp->master->internal; DB_THREAD_LOCK(hp->dbp); @@ -1432,7 +1463,7 @@ __ham_hdup(orig, new) DBC *curs; int ret; - if ((hashp = (HTAB *)malloc(sizeof(HTAB))) == NULL) + if ((hashp = (HTAB *)__db_malloc(sizeof(HTAB))) == NULL) return (ENOMEM); new->internal = hashp; @@ -1441,7 +1472,7 @@ __ham_hdup(orig, new) hashp->hlock = 0; hashp->hdr = NULL; hashp->hash = ((HTAB *)orig->internal)->hash; - if ((hashp->split_buf = (PAGE *)malloc(orig->pgsize)) == NULL) + if ((hashp->split_buf = (PAGE *)__db_malloc(orig->pgsize)) == NULL) return (ENOMEM); hashp->local_errno = 0; hashp->hash_accesses = 0; |