diff options
Diffstat (limited to 'db2/mp/mp_fget.c')
| -rw-r--r-- | db2/mp/mp_fget.c | 41 |
1 files changed, 25 insertions, 16 deletions
diff --git a/db2/mp/mp_fget.c b/db2/mp/mp_fget.c index a0364e92c3..3f99e60505 100644 --- a/db2/mp/mp_fget.c +++ b/db2/mp/mp_fget.c @@ -7,7 +7,7 @@ #include "config.h" #ifndef lint -static const char sccsid[] = "@(#)mp_fget.c 10.25 (Sleepycat) 9/23/97"; +static const char sccsid[] = "@(#)mp_fget.c 10.30 (Sleepycat) 10/25/97"; #endif /* not lint */ #ifndef NO_SYSTEM_INCLUDES @@ -87,14 +87,14 @@ memp_fget(dbmfp, pgnoaddr, flags, addrp) * We want to switch threads as often as possible. Sleep every time * we get a new page to make it more likely. */ - if (__sleep_on_every_page_get && (dbmp->dbenv == NULL || - dbmp->dbenv->db_yield == NULL || dbmp->dbenv->db_yield() != 0)) + if (__sleep_on_every_page_get && + (__db_yield == NULL || __db_yield() != 0)) __db_sleep(0, 1); #endif mp = dbmp->mp; mfp = dbmfp->mfp; - mf_offset = OFFSET(dbmp, mfp); + mf_offset = R_OFFSET(dbmp, mfp); addr = NULL; bhp = NULL; b_incr = b_inserted = readonly_alloc = ret = 0; @@ -137,7 +137,7 @@ memp_fget(dbmfp, pgnoaddr, flags, addrp) } } if (!readonly_alloc) { - addr = ADDR(dbmfp, *pgnoaddr * mfp->stat.st_pagesize); + addr = R_ADDR(dbmfp, *pgnoaddr * mfp->stat.st_pagesize); ++mp->stat.st_map; ++mfp->stat.st_map; @@ -159,9 +159,12 @@ memp_fget(dbmfp, pgnoaddr, flags, addrp) */ if (dbmfp->fd == -1) size = 0; - else if ((ret = __db_stat(dbmp->dbenv, - dbmfp->path, dbmfp->fd, &size, NULL)) != 0) + else if ((ret = + __db_ioinfo(dbmfp->path, dbmfp->fd, &size, NULL)) != 0) { + __db_err(dbmp->dbenv, + "%s: %s", dbmfp->path, strerror(ret)); goto err; + } *pgnoaddr = size == 0 ? 0 : (size - 1) / mfp->stat.st_pagesize; @@ -190,26 +193,29 @@ memp_fget(dbmfp, pgnoaddr, flags, addrp) goto found; } - /* If we haven't checked the BH list yet, do the search. */ + /* If we haven't checked the BH hash bucket queue, do the search. */ if (!LF_ISSET(DB_MPOOL_LAST | DB_MPOOL_NEW)) { - ++mp->stat.st_hash_searches; bucket = BUCKET(mp, mf_offset, *pgnoaddr); for (cnt = 0, bhp = SH_TAILQ_FIRST(&dbmp->htab[bucket], __bh); - bhp != NULL; bhp = SH_TAILQ_NEXT(bhp, mq, __bh)) { + bhp != NULL; bhp = SH_TAILQ_NEXT(bhp, hq, __bh)) { ++cnt; if (bhp->pgno == *pgnoaddr && bhp->mf_offset == mf_offset) { addr = bhp->buf; + ++mp->stat.st_hash_searches; if (cnt > mp->stat.st_hash_longest) mp->stat.st_hash_longest = cnt; mp->stat.st_hash_examined += cnt; goto found; } } - if (cnt > mp->stat.st_hash_longest) - mp->stat.st_hash_longest = cnt; - mp->stat.st_hash_examined += cnt; + if (cnt != 0) { + ++mp->stat.st_hash_searches; + if (cnt > mp->stat.st_hash_longest) + mp->stat.st_hash_longest = cnt; + mp->stat.st_hash_examined += cnt; + } } /* @@ -239,8 +245,9 @@ memp_fget(dbmfp, pgnoaddr, flags, addrp) * our region lock without screwing up the world. */ bucket = BUCKET(mp, mf_offset, *pgnoaddr); - SH_TAILQ_INSERT_HEAD(&dbmp->htab[bucket], bhp, mq, __bh); + SH_TAILQ_INSERT_HEAD(&dbmp->htab[bucket], bhp, hq, __bh); SH_TAILQ_INSERT_TAIL(&mp->bhq, bhp, q); + ++mp->stat.st_page_clean; b_inserted = 1; /* Set the page number, and associated MPOOLFILE. */ @@ -281,7 +288,8 @@ reread: if ((ret = __memp_pgread(dbmfp, * !!! * The __memp_pgread call discarded and reacquired the region * lock. Because the buffer reference count was incremented - * before the region lock was discarded the buffer didn't move. + * before the region lock was discarded the buffer can't move + * and its contents can't change. */ ++mp->stat.st_cache_miss; ++mfp->stat.st_cache_miss; @@ -305,7 +313,8 @@ found: /* Increment the reference count. */ * BH_LOCKED -- * I/O in progress, wait for it to finish. Because the buffer * reference count was incremented before the region lock was - * discarded we know the buffer didn't move. + * discarded we know the buffer can't move and its contents + * can't change. */ if (F_ISSET(bhp, BH_LOCKED)) { UNLOCKREGION(dbmp); |