spgist_stat

[gevel.git] / gevel.c

diff --git a/gevel.c b/gevel.c
index 86fb43e..ef8f3d9 100644 (file)
--- a/gevel.c
+++ b/gevel.c
@@ -8,6 +8,10 @@
 #include "access/gist.h"
 #include "access/gist_private.h"
 #include "access/gistscan.h"
+#if PG_VERSION_NUM >= 90200
+#include "access/spgist_private.h"
+#include "access/spgist.h"
+#endif
 #include "access/heapam.h"
 #include "catalog/index.h"
 #include "miscadmin.h"
@@ -58,7 +62,7 @@ PG_MODULE_MAGIC;
 
 static Relation
 gist_index_open(RangeVar *relvar) {
-#if PG_VERSION_NUM < 90100 
+#if PG_VERSION_NUM <= 90100 
        Oid relOid = RangeVarGetRelid(relvar, false);
 #else
        Oid relOid = RangeVarGetRelid(relvar, NoLock, false);
@@ -71,7 +75,7 @@ gist_index_open(RangeVar *relvar) {
 
 static Relation
 gin_index_open(RangeVar *relvar) {
-#if PG_VERSION_NUM < 90100 
+#if PG_VERSION_NUM <= 90100 
        Oid relOid = RangeVarGetRelid(relvar, false);
 #else
        Oid relOid = RangeVarGetRelid(relvar, NoLock, false);
@@ -835,3 +839,139 @@ gin_count_estimate(PG_FUNCTION_ARGS) {
        PG_RETURN_INT64(0);
 }
 #endif
+
+PG_FUNCTION_INFO_V1(spgist_stat);
+Datum spgist_stat(PG_FUNCTION_ARGS);
+Datum
+spgist_stat(PG_FUNCTION_ARGS)
+{
+#if PG_VERSION_NUM < 90200
+       elog(NOTICE, "Function is not working under PgSQL < 9.2");
+
+       PG_RETURN_TEXT_P(CStringGetTextDatum("???"));
+#else
+       text       *name = PG_GETARG_TEXT_P(0);
+       RangeVar   *relvar;
+       Relation        index;
+       BlockNumber blkno;
+       BlockNumber totalPages = 0,
+                               innerPages = 0,
+                               leafPages = 0,
+                               emptyPages = 0,
+                               deletedPages = 0;
+       double    usedSpace = 0.0;
+       char            res[1024];
+       int              bufferSize = -1;
+       int64      innerTuples = 0,
+                               leafTuples = 0,
+                               nAllTheSame = 0,
+                               nLeafPlaceholder = 0,
+                               nInnerPlaceholder = 0,
+                               nLeafRedirect = 0,
+                               nInnerRedirect = 0;
+
+#define IS_INDEX(r) ((r)->rd_rel->relkind == RELKIND_INDEX)
+#define IS_SPGIST(r) ((r)->rd_rel->relam == SPGIST_AM_OID)
+
+       relvar = makeRangeVarFromNameList(textToQualifiedNameList(name));
+       index = relation_openrv(relvar, AccessExclusiveLock);
+
+       if (!IS_INDEX(index) || !IS_SPGIST(index))
+               elog(ERROR, "relation \"%s\" is not an SPGiST index",
+                        RelationGetRelationName(index));
+
+       totalPages = RelationGetNumberOfBlocks(index);
+
+       for (blkno = SPGIST_HEAD_BLKNO; blkno < totalPages; blkno++)
+       {
+               Buffer    buffer;
+               Page            page;
+               int              pageFree;
+
+               buffer = ReadBuffer(index, blkno);
+               LockBuffer(buffer, BUFFER_LOCK_SHARE);
+
+               page = BufferGetPage(buffer);
+
+               if (PageIsNew(page) || SpGistPageIsDeleted(page))
+               {
+                       deletedPages++;
+                       UnlockReleaseBuffer(buffer);
+                       continue;
+               }
+
+               if (SpGistPageIsLeaf(page))
+               {
+                       leafPages++;
+                       leafTuples += PageGetMaxOffsetNumber(page);
+                       nLeafPlaceholder += SpGistPageGetOpaque(page)->nPlaceholder;
+                       nLeafRedirect += SpGistPageGetOpaque(page)->nRedirection;
+               }
+               else
+               {
+                       int      i,
+                                       max;
+
+                       innerPages++;
+                       max = PageGetMaxOffsetNumber(page);
+                       innerTuples += max;
+                       nInnerPlaceholder += SpGistPageGetOpaque(page)->nPlaceholder;
+                       nInnerRedirect += SpGistPageGetOpaque(page)->nRedirection;
+                       for (i = FirstOffsetNumber; i <= max; i++)
+                       {
+                               SpGistInnerTuple it;
+
+                               it = (SpGistInnerTuple) PageGetItem(page,
+                                                                                                       PageGetItemId(page, i));
+                               if (it->allTheSame)
+                                       nAllTheSame++;
+                       }
+               }
+
+               if (bufferSize < 0)
+                       bufferSize = BufferGetPageSize(buffer)
+                               - MAXALIGN(sizeof(SpGistPageOpaqueData))
+                               - SizeOfPageHeaderData;
+
+               pageFree = PageGetExactFreeSpace(page);
+
+               usedSpace += bufferSize - pageFree;
+
+               if (pageFree == bufferSize)
+                       emptyPages++;
+
+               UnlockReleaseBuffer(buffer);
+       }
+
+       index_close(index, AccessExclusiveLock);
+
+       totalPages--;                      /* discount metapage */
+
+       snprintf(res, sizeof(res),
+                        "totalPages:        %u\n"
+                        "deletedPages:      %u\n"
+                        "innerPages:        %u\n"
+                        "leafPages:         %u\n"
+                        "emptyPages:        %u\n"
+                        "usedSpace:         %.2f kbytes\n"
+                        "freeSpace:         %.2f kbytes\n"
+                        "fillRatio:         %.2f%%\n"
+                        "leafTuples:        " INT64_FORMAT "\n"
+                        "innerTuples:       " INT64_FORMAT "\n"
+                        "innerAllTheSame:   " INT64_FORMAT "\n"
+                        "leafPlaceholders:  " INT64_FORMAT "\n"
+                        "innerPlaceholders: " INT64_FORMAT "\n"
+                        "leafRedirects:     " INT64_FORMAT "\n"
+                        "innerRedirects:    " INT64_FORMAT,
+                        totalPages, deletedPages, innerPages, leafPages, emptyPages,
+                        usedSpace / 1024.0,
+                        (((double) bufferSize) * ((double) totalPages) - usedSpace) / 1024,
+                        100.0 * (usedSpace / (((double) bufferSize) * ((double) totalPages))),
+                        leafTuples, innerTuples, nAllTheSame,
+                        nLeafPlaceholder, nInnerPlaceholder,
+                        nLeafRedirect, nInnerRedirect);
+
+       PG_RETURN_TEXT_P(CStringGetTextDatum(res));
+#endif
+}
+