OSDN Git Service

Replace poorly-coded vac_find_eq routine with call to standard bsearch
authorTom Lane <tgl@sss.pgh.pa.us>
Thu, 17 May 2001 01:28:50 +0000 (01:28 +0000)
committerTom Lane <tgl@sss.pgh.pa.us>
Thu, 17 May 2001 01:28:50 +0000 (01:28 +0000)
library code.  Tweak progress messages to include elapsed real time,
not only CPU time.

src/backend/commands/vacuum.c

index 9a0dbdc..3e04dd7 100644 (file)
@@ -8,22 +8,23 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.190 2001/05/07 00:43:18 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.191 2001/05/17 01:28:50 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
 #include "postgres.h"
 
+#include <fcntl.h>
+#include <unistd.h>
+#include <time.h>
+#include <sys/time.h>
 #include <sys/types.h>
 #include <sys/file.h>
 #include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
 
 #ifndef HAVE_GETRUSAGE
 #include "rusagestub.h"
 #else
-#include <sys/time.h>
 #include <sys/resource.h>
 #endif
 
@@ -113,6 +114,11 @@ typedef struct VRelStats
        VTupleLink      vtlinks;
 } VRelStats;
 
+typedef struct VacRUsage
+{
+       struct timeval  tv;
+       struct rusage   ru;
+} VacRUsage;
 
 static MemoryContext vac_context = NULL;
 
@@ -144,13 +150,15 @@ static void get_indices(Relation relation, int *nindices, Relation **Irel);
 static void close_indices(int nindices, Relation *Irel);
 static IndexInfo **get_index_desc(Relation onerel, int nindices,
                           Relation *Irel);
-static void *vac_find_eq(void *bot, int nelem, int size, void *elm,
-                       int (*compar) (const void *, const void *));
+static void *vac_bsearch(const void *key, const void *base,
+                                                size_t nelem, size_t size,
+                                                int (*compar) (const void *, const void *));
 static int     vac_cmp_blk(const void *left, const void *right);
 static int     vac_cmp_offno(const void *left, const void *right);
 static int     vac_cmp_vtlinks(const void *left, const void *right);
 static bool enough_space(VacPage vacpage, Size len);
-static char *show_rusage(struct rusage * ru0);
+static void init_rusage(VacRUsage *ru0);
+static char *show_rusage(VacRUsage *ru0);
 
 
 /*
@@ -635,9 +643,9 @@ scan_heap(VRelStats *vacrelstats, Relation onerel,
        VTupleLink      vtlinks = (VTupleLink) palloc(100 * sizeof(VTupleLinkData));
        int                     num_vtlinks = 0;
        int                     free_vtlinks = 100;
-       struct rusage ru0;
+       VacRUsage       ru0;
 
-       getrusage(RUSAGE_SELF, &ru0);
+       init_rusage(&ru0);
 
        relname = RelationGetRelationName(onerel);
        elog(MESSAGE_LEVEL, "--Relation %s--", relname);
@@ -1062,9 +1070,9 @@ repair_frag(VRelStats *vacrelstats, Relation onerel,
        bool            isempty,
                                dowrite,
                                chain_tuple_moved;
-       struct rusage ru0;
+       VacRUsage       ru0;
 
-       getrusage(RUSAGE_SELF, &ru0);
+       init_rusage(&ru0);
 
        myXID = GetCurrentTransactionId();
        myCID = GetCurrentCommandId();
@@ -1360,10 +1368,10 @@ repair_frag(VRelStats *vacrelstats, Relation onerel,
 
                                                vtld.new_tid = tp.t_self;
                                                vtlp = (VTupleLink)
-                                                       vac_find_eq((void *) (vacrelstats->vtlinks),
+                                                       vac_bsearch((void *) &vtld,
+                                                                               (void *) (vacrelstats->vtlinks),
                                                                                vacrelstats->num_vtlinks,
                                                                                sizeof(VTupleLinkData),
-                                                                               (void *) &vtld,
                                                                                vac_cmp_vtlinks);
                                                if (vtlp == NULL)
                                                        elog(ERROR, "Parent tuple was not found");
@@ -2134,9 +2142,9 @@ scan_index(Relation indrel, long num_tuples)
        IndexScanDesc iscan;
        long            nitups;
        int                     nipages;
-       struct rusage ru0;
+       VacRUsage       ru0;
 
-       getrusage(RUSAGE_SELF, &ru0);
+       init_rusage(&ru0);
 
        /* walk through the entire index */
        iscan = index_beginscan(indrel, false, 0, (ScanKey) NULL);
@@ -2189,9 +2197,9 @@ vacuum_index(VacPageList vacpagelist, Relation indrel,
        long            num_index_tuples;
        int                     num_pages;
        VacPage         vp;
-       struct rusage ru0;
+       VacRUsage       ru0;
 
-       getrusage(RUSAGE_SELF, &ru0);
+       init_rusage(&ru0);
 
        /* walk through the entire index */
        iscan = index_beginscan(indrel, false, 0, (ScanKey) NULL);
@@ -2264,30 +2272,35 @@ tid_reaped(ItemPointer itemptr, VacPageList vacpagelist)
        ioffno = ItemPointerGetOffsetNumber(itemptr);
 
        vp = &vacpage;
-       vpp = (VacPage *) vac_find_eq((void *) (vacpagelist->pagedesc),
-                                  vacpagelist->num_pages, sizeof(VacPage), (void *) &vp,
+       vpp = (VacPage *) vac_bsearch((void *) &vp,
+                                                                 (void *) (vacpagelist->pagedesc),
+                                                                 vacpagelist->num_pages,
+                                                                 sizeof(VacPage),
                                                                  vac_cmp_blk);
 
        if (vpp == (VacPage *) NULL)
                return (VacPage) NULL;
-       vp = *vpp;
 
-       /* ok - we are on true page */
+       /* ok - we are on a partially or fully reaped page */
+       vp = *vpp;
 
        if (vp->offsets_free == 0)
-       {                                                       /* this is EmptyPage !!! */
+       {
+               /* this is EmptyPage, so claim all tuples on it are reaped!!! */
                return vp;
        }
 
-       voff = (OffsetNumber *) vac_find_eq((void *) (vp->offsets),
-                               vp->offsets_free, sizeof(OffsetNumber), (void *) &ioffno,
+       voff = (OffsetNumber *) vac_bsearch((void *) &ioffno,
+                                                                               (void *) (vp->offsets),
+                                                                               vp->offsets_free,
+                                                                               sizeof(OffsetNumber),
                                                                                vac_cmp_offno);
 
        if (voff == (OffsetNumber *) NULL)
                return (VacPage) NULL;
 
+       /* tid is reaped */
        return vp;
-
 }
 
 /*
@@ -2393,64 +2406,47 @@ vpage_insert(VacPageList vacpagelist, VacPage vpnew)
        }
        vacpagelist->pagedesc[vacpagelist->num_pages] = vpnew;
        (vacpagelist->num_pages)++;
-
 }
 
+/*
+ * vac_bsearch: just like standard C library routine bsearch(),
+ * except that we first test to see whether the target key is outside
+ * the range of the table entries.  This case is handled relatively slowly
+ * by the normal binary search algorithm (ie, no faster than any other key)
+ * but it occurs often enough in VACUUM to be worth optimizing.
+ */
 static void *
-vac_find_eq(void *bot, int nelem, int size, void *elm,
+vac_bsearch(const void *key, const void *base,
+                       size_t nelem, size_t size,
                        int (*compar) (const void *, const void *))
 {
        int                     res;
-       int                     last = nelem - 1;
-       int                     celm = nelem / 2;
-       bool            last_move,
-                               first_move;
-
-       last_move = first_move = true;
-       for (;;)
+       const void *last;
+
+       if (nelem == 0)
+               return NULL;
+       res = compar(key, base);
+       if (res < 0)
+               return NULL;
+       if (res == 0)
+               return (void *) base;
+       if (nelem > 1)
        {
-               if (first_move == true)
-               {
-                       res = compar(bot, elm);
-                       if (res > 0)
-                               return NULL;
-                       if (res == 0)
-                               return bot;
-                       first_move = false;
-               }
-               if (last_move == true)
-               {
-                       res = compar(elm, (void *) ((char *) bot + last * size));
-                       if (res > 0)
-                               return NULL;
-                       if (res == 0)
-                               return (void *) ((char *) bot + last * size);
-                       last_move = false;
-               }
-               res = compar(elm, (void *) ((char *) bot + celm * size));
-               if (res == 0)
-                       return (void *) ((char *) bot + celm * size);
-               if (res < 0)
-               {
-                       if (celm == 0)
-                               return NULL;
-                       last = celm - 1;
-                       celm = celm / 2;
-                       last_move = true;
-                       continue;
-               }
-
-               if (celm == last)
+               last = (const void *) ((const char *) base + (nelem - 1) * size);
+               res = compar(key, last);
+               if (res > 0)
                        return NULL;
-
-               last = last - celm - 1;
-               bot = (void *) ((char *) bot + (celm + 1) * size);
-               celm = (last + 1) / 2;
-               first_move = true;
+               if (res == 0)
+                       return (void *) last;
        }
-
+       if (nelem <= 2)
+               return NULL;                    /* already checked 'em all */
+       return bsearch(key, base, nelem, size, compar);
 }
 
+/*
+ * Comparator routines for use with qsort() and bsearch().
+ */
 static int
 vac_cmp_blk(const void *left, const void *right)
 {
@@ -2465,25 +2461,21 @@ vac_cmp_blk(const void *left, const void *right)
        if (lblk == rblk)
                return 0;
        return 1;
-
 }
 
 static int
 vac_cmp_offno(const void *left, const void *right)
 {
-
        if (*(OffsetNumber *) left < *(OffsetNumber *) right)
                return -1;
        if (*(OffsetNumber *) left == *(OffsetNumber *) right)
                return 0;
        return 1;
-
 }
 
 static int
 vac_cmp_vtlinks(const void *left, const void *right)
 {
-
        if (((VTupleLink) left)->new_tid.ip_blkid.bi_hi <
                ((VTupleLink) right)->new_tid.ip_blkid.bi_hi)
                return -1;
@@ -2505,7 +2497,6 @@ vac_cmp_vtlinks(const void *left, const void *right)
                ((VTupleLink) right)->new_tid.ip_posid)
                return 1;
        return 0;
-
 }
 
 
@@ -2603,36 +2594,55 @@ enough_space(VacPage vacpage, Size len)
 
 
 /*
+ * Initialize usage snapshot.
+ */
+static void
+init_rusage(VacRUsage *ru0)
+{
+       struct timezone tz;
+
+       getrusage(RUSAGE_SELF, &ru0->ru);
+       gettimeofday(&ru0->tv, &tz);
+}
+
+/*
  * Compute elapsed time since ru0 usage snapshot, and format into
  * a displayable string.  Result is in a static string, which is
  * tacky, but no one ever claimed that the Postgres backend is
  * threadable...
  */
 static char *
-show_rusage(struct rusage * ru0)
+show_rusage(VacRUsage *ru0)
 {
-       static char result[64];
-       struct rusage ru1;
+       static char result[100];
+       VacRUsage       ru1;
 
-       getrusage(RUSAGE_SELF, &ru1);
+       init_rusage(&ru1);
 
-       if (ru1.ru_stime.tv_usec < ru0->ru_stime.tv_usec)
+       if (ru1.tv.tv_usec < ru0->tv.tv_usec)
+       {
+               ru1.tv.tv_sec--;
+               ru1.tv.tv_usec += 1000000;
+       }
+       if (ru1.ru.ru_stime.tv_usec < ru0->ru.ru_stime.tv_usec)
        {
-               ru1.ru_stime.tv_sec--;
-               ru1.ru_stime.tv_usec += 1000000;
+               ru1.ru.ru_stime.tv_sec--;
+               ru1.ru.ru_stime.tv_usec += 1000000;
        }
-       if (ru1.ru_utime.tv_usec < ru0->ru_utime.tv_usec)
+       if (ru1.ru.ru_utime.tv_usec < ru0->ru.ru_utime.tv_usec)
        {
-               ru1.ru_utime.tv_sec--;
-               ru1.ru_utime.tv_usec += 1000000;
+               ru1.ru.ru_utime.tv_sec--;
+               ru1.ru.ru_utime.tv_usec += 1000000;
        }
 
        snprintf(result, sizeof(result),
-                        "CPU %d.%02ds/%d.%02du sec.",
-                        (int) (ru1.ru_stime.tv_sec - ru0->ru_stime.tv_sec),
-                        (int) (ru1.ru_stime.tv_usec - ru0->ru_stime.tv_usec) / 10000,
-                        (int) (ru1.ru_utime.tv_sec - ru0->ru_utime.tv_sec),
-                  (int) (ru1.ru_utime.tv_usec - ru0->ru_utime.tv_usec) / 10000);
+                        "CPU %d.%02ds/%d.%02du sec elapsed %d.%02d sec.",
+                        (int) (ru1.ru.ru_stime.tv_sec - ru0->ru.ru_stime.tv_sec),
+                        (int) (ru1.ru.ru_stime.tv_usec - ru0->ru.ru_stime.tv_usec) / 10000,
+                        (int) (ru1.ru.ru_utime.tv_sec - ru0->ru.ru_utime.tv_sec),
+                        (int) (ru1.ru.ru_utime.tv_usec - ru0->ru.ru_utime.tv_usec) / 10000,
+                        (int) (ru1.tv.tv_sec - ru0->tv.tv_sec),
+                        (int) (ru1.tv.tv_usec - ru0->tv.tv_usec) / 10000);
 
        return result;
 }