A few further tweaks to shared memory space estimation.

This change brings the default size of the main shmem block back under 1MB,
which is a fairly popular value for the kernel's SHMMAX parameter.

diff --git a/src/backend/storage/ipc/ipci.c b/src/backend/storage/ipc/ipci.c
index 2f5d1d3..e7d6e70 100644 (file)
--- a/src/backend/storage/ipc/ipci.c
+++ b/src/backend/storage/ipc/ipci.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/storage/ipc/ipci.c,v 1.22 1999/02/22 06:16:49 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/storage/ipc/ipci.c,v 1.23 1999/03/06 21:17:41 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -77,14 +77,12 @@ CreateSharedMemoryAndSemaphores(IPCKey key, int maxBackends)
         * Size of the primary shared-memory block is estimated via
         * moderately-accurate estimates for the big hogs, plus 100K for
         * the stuff that's too small to bother with estimating.
-        * Then we add 10% for a safety margin.
         */
        size = BufferShmemSize() + LockShmemSize(maxBackends);
 #ifdef STABLE_MEMORY_STORAGE
        size += MMShmemSize();
 #endif
        size += 100000;
-       size += size / 10;
 
        if (DebugLvl > 1)
        {

diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index ed9a5b3..2f822ad 100644 (file)
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lock.c,v 1.45 1999/02/22 06:16:52 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/storage/lmgr/lock.c,v 1.46 1999/03/06 21:17:44 tgl Exp $
  *
  * NOTES
  *       Outside modules can create a lock table and acquire/release
@@ -339,8 +339,8 @@ LockMethodTableInit(char *tabName,
         * to find the different locks.
         * ----------------------
         */
-       info.keysize = sizeof(LOCKTAG);
-       info.datasize = sizeof(LOCK);
+       info.keysize = SHMEM_LOCKTAB_KEYSIZE;
+       info.datasize = SHMEM_LOCKTAB_DATASIZE;
        info.hash = tag_hash;
        hash_flags = (HASH_ELEM | HASH_FUNCTION);
 
@@ -361,8 +361,8 @@ LockMethodTableInit(char *tabName,
         * the same lock, additional information must be saved (locks per tx).
         * -------------------------
         */
-       info.keysize = XID_TAGSIZE;
-       info.datasize = sizeof(XIDLookupEnt);
+       info.keysize = SHMEM_XIDTAB_KEYSIZE;
+       info.datasize = SHMEM_XIDTAB_DATASIZE;
        info.hash = tag_hash;
        hash_flags = (HASH_ELEM | HASH_FUNCTION);
 
@@ -1488,13 +1488,18 @@ LockShmemSize(int maxBackends)
 
        /* lockHash table */
        size += hash_estimate_size(NLOCKENTS(maxBackends),
-                                                          sizeof(LOCKTAG),
-                                                          sizeof(LOCK));
+                                                          SHMEM_LOCKTAB_KEYSIZE,
+                                                          SHMEM_LOCKTAB_DATASIZE);
 
        /* xidHash table */
        size += hash_estimate_size(maxBackends,
-                                                          XID_TAGSIZE,
-                                                          sizeof(XIDLookupEnt));
+                                                          SHMEM_XIDTAB_KEYSIZE,
+                                                          SHMEM_XIDTAB_DATASIZE);
+
+       /* Since the lockHash entry count above is only an estimate,
+        * add 10% safety margin.
+        */
+       size += size / 10;
 
        return size;
 }

diff --git a/src/backend/storage/smgr/mm.c b/src/backend/storage/smgr/mm.c
index 603ee59..2d5c1cd 100644 (file)
--- a/src/backend/storage/smgr/mm.c
+++ b/src/backend/storage/smgr/mm.c
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/storage/smgr/Attic/mm.c,v 1.14 1999/02/22 06:16:57 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/storage/smgr/Attic/mm.c,v 1.15 1999/03/06 21:17:50 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -110,7 +110,7 @@ mminit()
        }
 
        info.keysize = sizeof(MMCacheTag);
-       info.datasize = sizeof(int);
+       info.datasize = sizeof(MMHashEntry) - sizeof(MMCacheTag);
        info.hash = tag_hash;
 
        MMCacheHT = (HTAB *) ShmemInitHash("Main memory store HT",
@@ -124,7 +124,7 @@ mminit()
        }
 
        info.keysize = sizeof(MMRelTag);
-       info.datasize = sizeof(int);
+       info.datasize = sizeof(MMRelHashEntry) - sizeof(MMRelTag);
        info.hash = tag_hash;
 
        MMRelCacheHT = (HTAB *) ShmemInitHash("Main memory rel HT",

diff --git a/src/backend/utils/hash/dynahash.c b/src/backend/utils/hash/dynahash.c
index dcf4e4c..f9d8712 100644 (file)
--- a/src/backend/utils/hash/dynahash.c
+++ b/src/backend/utils/hash/dynahash.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/utils/hash/dynahash.c,v 1.19 1999/02/22 06:16:47 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/utils/hash/dynahash.c,v 1.20 1999/03/06 21:17:56 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -373,18 +373,23 @@ hash_estimate_size(long num_entries, long keysize, long datasize)
        long    size = 0;
        long    nBuckets,
                        nSegments,
+                       nDirEntries,
                        nRecordAllocs,
                        recordSize;
 
        /* estimate number of buckets wanted */
        nBuckets = 1L << my_log2((num_entries - 1) / DEF_FFACTOR + 1);
        /* # of segments needed for nBuckets */
-       nSegments = (nBuckets - 1) / DEF_SEGSIZE + 1;
+       nSegments = 1L << my_log2((nBuckets - 1) / DEF_SEGSIZE + 1);
+       /* directory entries */
+       nDirEntries = DEF_DIRSIZE;
+       while (nDirEntries < nSegments)
+               nDirEntries <<= 1;              /* dir_alloc doubles dsize at each call */
 
        /* fixed control info */
        size += MAXALIGN(sizeof(HHDR)); /* but not HTAB, per above */
-       /* directory, assumed to be of size DEF_DIRSIZE */
-       size += MAXALIGN(DEF_DIRSIZE * sizeof(SEG_OFFSET));
+       /* directory */
+       size += MAXALIGN(nDirEntries * sizeof(SEG_OFFSET));
        /* segments */
        size += nSegments * MAXALIGN(DEF_SEGSIZE * sizeof(BUCKET_INDEX));
        /* records --- allocated in groups of BUCKET_ALLOC_INCR */
@@ -408,9 +413,6 @@ hash_estimate_size(long num_entries, long keysize, long datasize)
 void
 hash_destroy(HTAB *hashp)
 {
-       /* cannot destroy a shared memory hash table */
-       Assert(!hashp->segbase);
-
        if (hashp != NULL)
        {
                SEG_OFFSET      segNum;
@@ -422,6 +424,13 @@ hash_destroy(HTAB *hashp)
                                        q;
                ELEMENT    *curr;
 
+               /* cannot destroy a shared memory hash table */
+               Assert(!hashp->segbase);
+               /* allocation method must be one we know how to free, too */
+               Assert(hashp->alloc == (dhalloc_ptr) MEM_ALLOC);
+
+               hash_stats("destroy", hashp);
+
                for (segNum = 0; nsegs > 0; nsegs--, segNum++)
                {
 
@@ -435,11 +444,10 @@ hash_destroy(HTAB *hashp)
                                        MEM_FREE((char *) curr);
                                }
                        }
-                       free((char *) segp);
+                       MEM_FREE((char *) segp);
                }
                MEM_FREE((char *) hashp->dir);
                MEM_FREE((char *) hashp->hctl);
-               hash_stats("destroy", hashp);
                MEM_FREE((char *) hashp);
        }
 }

diff --git a/src/include/storage/lock.h b/src/include/storage/lock.h
index ce1f301..da77f1d 100644 (file)
--- a/src/include/storage/lock.h
+++ b/src/include/storage/lock.h
@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: lock.h,v 1.23 1999/02/21 01:41:47 tgl Exp $
+ * $Id: lock.h,v 1.24 1999/03/06 21:17:43 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -57,8 +57,6 @@ typedef int LOCKMETHOD;
 #define USER_LOCKMETHOD                2
 #define MIN_LOCKMETHOD         DEFAULT_LOCKMETHOD
 
-/*typedef struct LOCK LOCK; */
-
 
 typedef struct LTAG
 {
@@ -174,6 +172,9 @@ typedef struct XIDLookupEnt
        SHM_QUEUE       queue;
 } XIDLookupEnt;
 
+#define SHMEM_XIDTAB_KEYSIZE  sizeof(XIDTAG)
+#define SHMEM_XIDTAB_DATASIZE (sizeof(XIDLookupEnt) - SHMEM_XIDTAB_KEYSIZE)
+
 #define XID_TAGSIZE (sizeof(XIDTAG))
 #define XIDENT_LOCKMETHOD(xident) (XIDTAG_LOCKMETHOD((xident).tag))
 
@@ -210,6 +211,9 @@ typedef struct LOCK
        int                     nActive;
 } LOCK;
 
+#define SHMEM_LOCKTAB_KEYSIZE  sizeof(LOCKTAG)
+#define SHMEM_LOCKTAB_DATASIZE (sizeof(LOCK) - SHMEM_LOCKTAB_KEYSIZE)
+
 #define LOCK_LOCKMETHOD(lock) (LOCKTAG_LOCKMETHOD((lock).tag))
 
 #define LockGetLock_nHolders(l) l->nHolders