bt_stat.c
上传用户:romrleung
上传日期:2022-05-23
资源大小:18897k
文件大小:11k
- /*-
- * See the file LICENSE for redistribution information.
- *
- * Copyright (c) 1996-2002
- * Sleepycat Software. All rights reserved.
- */
- #include "db_config.h"
- #ifndef lint
- static const char revid[] = "$Id: bt_stat.c,v 11.52 2002/05/30 15:40:27 krinsky Exp $";
- #endif /* not lint */
- #ifndef NO_SYSTEM_INCLUDES
- #include <sys/types.h>
- #include <string.h>
- #endif
- #include "db_int.h"
- #include "dbinc/db_page.h"
- #include "dbinc/db_shash.h"
- #include "dbinc/btree.h"
- #include "dbinc/lock.h"
- #include "dbinc/log.h"
- /*
- * __bam_stat --
- * Gather/print the btree statistics
- *
- * PUBLIC: int __bam_stat __P((DB *, void *, u_int32_t));
- */
- int
- __bam_stat(dbp, spp, flags)
- DB *dbp;
- void *spp;
- u_int32_t flags;
- {
- BTMETA *meta;
- BTREE *t;
- BTREE_CURSOR *cp;
- DBC *dbc;
- DB_BTREE_STAT *sp;
- DB_LOCK lock, metalock;
- DB_MPOOLFILE *mpf;
- PAGE *h;
- db_pgno_t pgno;
- int ret, t_ret, write_meta;
- PANIC_CHECK(dbp->dbenv);
- DB_ILLEGAL_BEFORE_OPEN(dbp, "DB->stat");
- meta = NULL;
- t = dbp->bt_internal;
- sp = NULL;
- LOCK_INIT(metalock);
- LOCK_INIT(lock);
- mpf = dbp->mpf;
- h = NULL;
- ret = 0;
- write_meta = 0;
- /* Check for invalid flags. */
- if ((ret = __db_statchk(dbp, flags)) != 0)
- return (ret);
- /* Acquire a cursor. */
- if ((ret = dbp->cursor(dbp, NULL, &dbc, 0)) != 0)
- return (ret);
- cp = (BTREE_CURSOR *)dbc->internal;
- DEBUG_LWRITE(dbc, NULL, "bam_stat", NULL, NULL, flags);
- /* Allocate and clear the structure. */
- if ((ret = __os_umalloc(dbp->dbenv, sizeof(*sp), &sp)) != 0)
- goto err;
- memset(sp, 0, sizeof(*sp));
- /* Get the metadata page for the entire database. */
- pgno = PGNO_BASE_MD;
- if ((ret = __db_lget(dbc, 0, pgno, DB_LOCK_READ, 0, &metalock)) != 0)
- goto err;
- if ((ret = mpf->get(mpf, &pgno, 0, (PAGE **)&meta)) != 0)
- goto err;
- if (flags == DB_RECORDCOUNT || flags == DB_CACHED_COUNTS)
- flags = DB_FAST_STAT;
- if (flags == DB_FAST_STAT)
- goto meta_only;
- /* Walk the metadata free list, counting pages. */
- for (sp->bt_free = 0, pgno = meta->dbmeta.free; pgno != PGNO_INVALID;) {
- ++sp->bt_free;
- if ((ret = mpf->get(mpf, &pgno, 0, &h)) != 0)
- goto err;
- pgno = h->next_pgno;
- if ((ret = mpf->put(mpf, h, 0)) != 0)
- goto err;
- h = NULL;
- }
- /* Get the root page. */
- pgno = cp->root;
- if ((ret = __db_lget(dbc, 0, pgno, DB_LOCK_READ, 0, &lock)) != 0)
- goto err;
- if ((ret = mpf->get(mpf, &pgno, 0, &h)) != 0)
- goto err;
- /* Get the levels from the root page. */
- sp->bt_levels = h->level;
- /* Discard the root page. */
- if ((ret = mpf->put(mpf, h, 0)) != 0)
- goto err;
- h = NULL;
- __LPUT(dbc, lock);
- /* Walk the tree. */
- if ((ret = __bam_traverse(dbc,
- DB_LOCK_READ, cp->root, __bam_stat_callback, sp)) != 0)
- goto err;
- /*
- * Get the subdatabase metadata page if it's not the same as the
- * one we already have.
- */
- write_meta = !F_ISSET(dbp, DB_AM_RDONLY);
- meta_only:
- if (t->bt_meta != PGNO_BASE_MD || write_meta != 0) {
- if ((ret = mpf->put(mpf, meta, 0)) != 0)
- goto err;
- meta = NULL;
- __LPUT(dbc, metalock);
- if ((ret = __db_lget(dbc,
- 0, t->bt_meta, write_meta == 0 ?
- DB_LOCK_READ : DB_LOCK_WRITE, 0, &metalock)) != 0)
- goto err;
- if ((ret = mpf->get(mpf, &t->bt_meta, 0, (PAGE **)&meta)) != 0)
- goto err;
- }
- if (flags == DB_FAST_STAT) {
- if (dbp->type == DB_RECNO ||
- (dbp->type == DB_BTREE && F_ISSET(dbp, DB_AM_RECNUM))) {
- if ((ret = __db_lget(dbc, 0,
- cp->root, DB_LOCK_READ, 0, &lock)) != 0)
- goto err;
- if ((ret =
- mpf->get(mpf, &cp->root, 0, (PAGE **)&h)) != 0)
- goto err;
- sp->bt_nkeys = RE_NREC(h);
- } else
- sp->bt_nkeys = meta->dbmeta.key_count;
- sp->bt_ndata = meta->dbmeta.record_count;
- }
- /* Get metadata page statistics. */
- sp->bt_metaflags = meta->dbmeta.flags;
- sp->bt_maxkey = meta->maxkey;
- sp->bt_minkey = meta->minkey;
- sp->bt_re_len = meta->re_len;
- sp->bt_re_pad = meta->re_pad;
- sp->bt_pagesize = meta->dbmeta.pagesize;
- sp->bt_magic = meta->dbmeta.magic;
- sp->bt_version = meta->dbmeta.version;
- if (write_meta != 0) {
- meta->dbmeta.key_count = sp->bt_nkeys;
- meta->dbmeta.record_count = sp->bt_ndata;
- }
- *(DB_BTREE_STAT **)spp = sp;
- err: /* Discard the second page. */
- __LPUT(dbc, lock);
- if (h != NULL && (t_ret = mpf->put(mpf, h, 0)) != 0 && ret == 0)
- ret = t_ret;
- /* Discard the metadata page. */
- __LPUT(dbc, metalock);
- if (meta != NULL && (t_ret = mpf->put(
- mpf, meta, write_meta == 0 ? 0 : DB_MPOOL_DIRTY)) != 0 && ret == 0)
- ret = t_ret;
- if ((t_ret = dbc->c_close(dbc)) != 0 && ret == 0)
- ret = t_ret;
- if (ret != 0 && sp != NULL) {
- __os_ufree(dbp->dbenv, sp);
- *(DB_BTREE_STAT **)spp = NULL;
- }
- return (ret);
- }
- /*
- * __bam_traverse --
- * Walk a Btree database.
- *
- * PUBLIC: int __bam_traverse __P((DBC *, db_lockmode_t,
- * PUBLIC: db_pgno_t, int (*)(DB *, PAGE *, void *, int *), void *));
- */
- int
- __bam_traverse(dbc, mode, root_pgno, callback, cookie)
- DBC *dbc;
- db_lockmode_t mode;
- db_pgno_t root_pgno;
- int (*callback)__P((DB *, PAGE *, void *, int *));
- void *cookie;
- {
- BINTERNAL *bi;
- BKEYDATA *bk;
- DB *dbp;
- DB_LOCK lock;
- DB_MPOOLFILE *mpf;
- PAGE *h;
- RINTERNAL *ri;
- db_indx_t indx;
- int already_put, ret, t_ret;
- dbp = dbc->dbp;
- mpf = dbp->mpf;
- already_put = 0;
- if ((ret = __db_lget(dbc, 0, root_pgno, mode, 0, &lock)) != 0)
- return (ret);
- if ((ret = mpf->get(mpf, &root_pgno, 0, &h)) != 0) {
- __LPUT(dbc, lock);
- return (ret);
- }
- switch (TYPE(h)) {
- case P_IBTREE:
- for (indx = 0; indx < NUM_ENT(h); indx += O_INDX) {
- bi = GET_BINTERNAL(dbp, h, indx);
- if (B_TYPE(bi->type) == B_OVERFLOW &&
- (ret = __db_traverse_big(dbp,
- ((BOVERFLOW *)bi->data)->pgno,
- callback, cookie)) != 0)
- goto err;
- if ((ret = __bam_traverse(
- dbc, mode, bi->pgno, callback, cookie)) != 0)
- goto err;
- }
- break;
- case P_IRECNO:
- for (indx = 0; indx < NUM_ENT(h); indx += O_INDX) {
- ri = GET_RINTERNAL(dbp, h, indx);
- if ((ret = __bam_traverse(
- dbc, mode, ri->pgno, callback, cookie)) != 0)
- goto err;
- }
- break;
- case P_LBTREE:
- for (indx = 0; indx < NUM_ENT(h); indx += P_INDX) {
- bk = GET_BKEYDATA(dbp, h, indx);
- if (B_TYPE(bk->type) == B_OVERFLOW &&
- (ret = __db_traverse_big(dbp,
- GET_BOVERFLOW(dbp, h, indx)->pgno,
- callback, cookie)) != 0)
- goto err;
- bk = GET_BKEYDATA(dbp, h, indx + O_INDX);
- if (B_TYPE(bk->type) == B_DUPLICATE &&
- (ret = __bam_traverse(dbc, mode,
- GET_BOVERFLOW(dbp, h, indx + O_INDX)->pgno,
- callback, cookie)) != 0)
- goto err;
- if (B_TYPE(bk->type) == B_OVERFLOW &&
- (ret = __db_traverse_big(dbp,
- GET_BOVERFLOW(dbp, h, indx + O_INDX)->pgno,
- callback, cookie)) != 0)
- goto err;
- }
- break;
- case P_LDUP:
- case P_LRECNO:
- for (indx = 0; indx < NUM_ENT(h); indx += O_INDX) {
- bk = GET_BKEYDATA(dbp, h, indx);
- if (B_TYPE(bk->type) == B_OVERFLOW &&
- (ret = __db_traverse_big(dbp,
- GET_BOVERFLOW(dbp, h, indx)->pgno,
- callback, cookie)) != 0)
- goto err;
- }
- break;
- }
- ret = callback(dbp, h, cookie, &already_put);
- err: if (!already_put && (t_ret = mpf->put(mpf, h, 0)) != 0 && ret != 0)
- ret = t_ret;
- __LPUT(dbc, lock);
- return (ret);
- }
- /*
- * __bam_stat_callback --
- * Statistics callback.
- *
- * PUBLIC: int __bam_stat_callback __P((DB *, PAGE *, void *, int *));
- */
- int
- __bam_stat_callback(dbp, h, cookie, putp)
- DB *dbp;
- PAGE *h;
- void *cookie;
- int *putp;
- {
- DB_BTREE_STAT *sp;
- db_indx_t indx, *inp, top;
- u_int8_t type;
- sp = cookie;
- *putp = 0;
- top = NUM_ENT(h);
- inp = P_INP(dbp, h);
- switch (TYPE(h)) {
- case P_IBTREE:
- case P_IRECNO:
- ++sp->bt_int_pg;
- sp->bt_int_pgfree += P_FREESPACE(dbp, h);
- break;
- case P_LBTREE:
- /* Correct for on-page duplicates and deleted items. */
- for (indx = 0; indx < top; indx += P_INDX) {
- if (indx + P_INDX >= top ||
- inp[indx] != inp[indx + P_INDX])
- ++sp->bt_nkeys;
- type = GET_BKEYDATA(dbp, h, indx + O_INDX)->type;
- if (!B_DISSET(type) && B_TYPE(type) != B_DUPLICATE)
- ++sp->bt_ndata;
- }
- ++sp->bt_leaf_pg;
- sp->bt_leaf_pgfree += P_FREESPACE(dbp, h);
- break;
- case P_LRECNO:
- /*
- * If walking a recno tree, then each of these items is a key.
- * Otherwise, we're walking an off-page duplicate set.
- */
- if (dbp->type == DB_RECNO) {
- sp->bt_nkeys += top;
- /*
- * Correct for deleted items in non-renumbering
- * Recno databases.
- */
- if (F_ISSET(dbp, DB_AM_RENUMBER))
- sp->bt_ndata += top;
- else
- for (indx = 0; indx < top; indx += O_INDX) {
- type = GET_BKEYDATA(dbp, h, indx)->type;
- if (!B_DISSET(type))
- ++sp->bt_ndata;
- }
- ++sp->bt_leaf_pg;
- sp->bt_leaf_pgfree += P_FREESPACE(dbp, h);
- } else {
- sp->bt_ndata += top;
- ++sp->bt_dup_pg;
- sp->bt_dup_pgfree += P_FREESPACE(dbp, h);
- }
- break;
- case P_LDUP:
- /* Correct for deleted items. */
- for (indx = 0; indx < top; indx += O_INDX)
- if (!B_DISSET(GET_BKEYDATA(dbp, h, indx)->type))
- ++sp->bt_ndata;
- ++sp->bt_dup_pg;
- sp->bt_dup_pgfree += P_FREESPACE(dbp, h);
- break;
- case P_OVERFLOW:
- ++sp->bt_over_pg;
- sp->bt_over_pgfree += P_OVFLSPACE(dbp, dbp->pgsize, h);
- break;
- default:
- return (__db_pgfmt(dbp->dbenv, h->pgno));
- }
- return (0);
- }
- /*
- * __bam_key_range --
- * Return proportion of keys relative to given key. The numbers are
- * slightly skewed due to on page duplicates.
- *
- * PUBLIC: int __bam_key_range __P((DB *,
- * PUBLIC: DB_TXN *, DBT *, DB_KEY_RANGE *, u_int32_t));
- */
- int
- __bam_key_range(dbp, txn, dbt, kp, flags)
- DB *dbp;
- DB_TXN *txn;
- DBT *dbt;
- DB_KEY_RANGE *kp;
- u_int32_t flags;
- {
- BTREE_CURSOR *cp;
- DBC *dbc;
- EPG *sp;
- double factor;
- int exact, ret, t_ret;
- PANIC_CHECK(dbp->dbenv);
- DB_ILLEGAL_BEFORE_OPEN(dbp, "DB->key_range");
- if (flags != 0)
- return (__db_ferr(dbp->dbenv, "DB->key_range", 0));
- /* Check for consistent transaction usage. */
- if ((ret = __db_check_txn(dbp, txn, DB_LOCK_INVALIDID, 1)) != 0)
- return (ret);
- /* Acquire a cursor. */
- if ((ret = dbp->cursor(dbp, txn, &dbc, 0)) != 0)
- return (ret);
- DEBUG_LWRITE(dbc, NULL, "bam_key_range", NULL, NULL, 0);
- if ((ret = __bam_search(dbc, PGNO_INVALID,
- dbt, S_STK_ONLY, 1, NULL, &exact)) != 0)
- goto err;
- cp = (BTREE_CURSOR *)dbc->internal;
- kp->less = kp->greater = 0.0;
- factor = 1.0;
- /* Correct the leaf page. */
- cp->csp->entries /= 2;
- cp->csp->indx /= 2;
- for (sp = cp->sp; sp <= cp->csp; ++sp) {
- /*
- * At each level we know that pages greater than indx contain
- * keys greater than what we are looking for and those less
- * than indx are less than. The one pointed to by indx may
- * have some less, some greater or even equal. If indx is
- * equal to the number of entries, then the key is out of range
- * and everything is less.
- */
- if (sp->indx == 0)
- kp->greater += factor * (sp->entries - 1)/sp->entries;
- else if (sp->indx == sp->entries)
- kp->less += factor;
- else {
- kp->less += factor * sp->indx / sp->entries;
- kp->greater += factor *
- (sp->entries - sp->indx - 1) / sp->entries;
- }
- factor *= 1.0/sp->entries;
- }
- /*
- * If there was an exact match then assign 1 n'th to the key itself.
- * Otherwise that factor belongs to those greater than the key, unless
- * the key was out of range.
- */
- if (exact)
- kp->equal = factor;
- else {
- if (kp->less != 1)
- kp->greater += factor;
- kp->equal = 0;
- }
- BT_STK_CLR(cp);
- err: if ((t_ret = dbc->c_close(dbc)) != 0 && ret == 0)
- ret = t_ret;
- return (ret);
- }