Add additional DBSTATUS options for measuring the hit and miss rates against

the lookaside memory pool - information useful in tuning the lookaside size.
Currently experimental pending analysis of performance impact.

FossilOrigin-Name: 34613f1dc54c638531ca2f5907b71fbe8841233e

diff --git a/manifest b/manifest
index 8023d4f93ec86dc2c4ad10e0c03da1bbe61f67f5..c423fa11b39622ebbccfb0dcced4d3a050c8370e 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,8 +1,8 @@
 -----BEGIN PGP SIGNED MESSAGE-----
 Hash: SHA1
 
-C Add\sthe\s"-heap"\soption\sto\sthe\scommand-line\sshell\s-\sto\sallocate\sa\sfixed\sheap\nfor\suse\swith\sSQLITE_ENABLE_MEMSYS5.
-D 2010-12-17T14:03:02
+C Add\sadditional\sDBSTATUS\soptions\sfor\smeasuring\sthe\shit\sand\smiss\srates\sagainst\nthe\slookaside\smemory\spool\s-\sinformation\suseful\sin\stuning\sthe\slookaside\ssize.\nCurrently\sexperimental\spending\sanalysis\sof\sperformance\simpact.
+D 2010-12-20T15:51:59
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 4547616ad2286053af6ccccefa242dc925e49bf0
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -145,7 +145,7 @@ F src/legacy.c a199d7683d60cef73089e892409113e69c23a99f
 F src/lempar.c 7f026423f4d71d989e719a743f98a1cbd4e6d99e
 F src/loadext.c 8af9fcc75708d60b88636ccba38b4a7b3c155c3e
 F src/main.c b82ea116fc9e2e059e77b9a1aba76267681f7149
-F src/malloc.c 3d7284cd9346ab6e3945535761e68c23c6cf40ef
+F src/malloc.c 92d59a007d7a42857d4e9454aa25b6b703286be1
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c 00bd8265c81abb665c48fea1e0c234eb3b922206
 F src/mem2.c e307323e86b5da1853d7111b68fd6b84ad6f09cf
@@ -179,11 +179,11 @@ F src/resolve.c 1c0f32b64f8e3f555fe1f732f9d6f501a7f05706
 F src/rowset.c 69afa95a97c524ba6faf3805e717b5b7ae85a697
 F src/select.c 8a7ba246b0b4bb45df7fbc52681728a0e3deaaa7
 F src/shell.c 9afa9bdd62142e254b4581a77b43080d3ffd4ef4
-F src/sqlite.h.in 83fed95ea6acbac51c48eba5bd93933f3795ee91
+F src/sqlite.h.in 2f1fd40e8ba7c0a51eb755e0b6af236ce692325b
 F src/sqlite3ext.h c90bd5507099f62043832d73f6425d8d5c5da754
-F src/sqliteInt.h b96d5ddb8b419a2ed7cf69a7778b53872d73e8a7
+F src/sqliteInt.h 3ef5fc89a4c9755a08a68de107493785a284e27c
 F src/sqliteLimit.h a17dcd3fb775d63b64a43a55c54cb282f9726f44
-F src/status.c 496913d4e8441195f6f2a75b1c95993a45b9b30b
+F src/status.c 4997380fbb915426fef9e500b4872e79c99267fc
 F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
 F src/tclsqlite.c 77c5c4b8ac7b2d94ee480e1ad626fbd921d948e4
 F src/test1.c 397809a3069c171a507a49b6f6edfc4255b0afbc
@@ -897,14 +897,18 @@ F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P df430be59d0766a34a94ab85fec9aa3c3baeb740
-R 393588dace853776e15dcf6aab702ada
+P 74fff692345fed4b247e2b34c1e63b4d50cddfd4
+R 5082873d15f794ab949991323071e42f
+T *bgcolor * #c0ffc0
+T *branch * experimental
+T *sym-experimental *
+T -sym-trunk *
 U drh
-Z 6ec40d9633f2b97ac37609013c97cbd2
+Z d0e19bf0b71d36c4c32d327aba382999
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.6 (GNU/Linux)
 
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-=DrJ4
+iD8DBQFND3uioxKgR168RlERAirTAJ0bHLsmerXov5fiom51y80kBrhKkACfXfos
+ossaFA/wslQt5YU5JPaXj1I=
+=Q2Je
 -----END PGP SIGNATURE-----

diff --git a/manifest.uuid b/manifest.uuid
index 0a6617ada82897c210d1b5cd14903af3e32d8d9c..dfd9a9a2d1051f6a030bd45c69bfb1a87a733dae 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-74fff692345fed4b247e2b34c1e63b4d50cddfd4
\ No newline at end of file
+34613f1dc54c638531ca2f5907b71fbe8841233e
\ No newline at end of file

diff --git a/src/malloc.c b/src/malloc.c
index 2c789794986c9b92e9fb87538307d8fb68a772d5..a3a9e0fe2c547081d8980152bb4f065a33b7054d 100644 (file)
--- a/src/malloc.c
+++ b/src/malloc.c
@@ -616,14 +616,20 @@ void *sqlite3DbMallocRaw(sqlite3 *db, int n){
     if( db->mallocFailed ){
       return 0;
     }
-    if( db->lookaside.bEnabled && n<=db->lookaside.sz
-         && (pBuf = db->lookaside.pFree)!=0 ){
-      db->lookaside.pFree = pBuf->pNext;
-      db->lookaside.nOut++;
-      if( db->lookaside.nOut>db->lookaside.mxOut ){
-        db->lookaside.mxOut = db->lookaside.nOut;
+    if( db->lookaside.bEnabled ){
+      if( n>db->lookaside.sz ){
+        db->lookaside.anStat[1]++;
+      }else if( (pBuf = db->lookaside.pFree)==0 ){
+        db->lookaside.anStat[2]++;
+      }else{
+        db->lookaside.pFree = pBuf->pNext;
+        db->lookaside.nOut++;
+        db->lookaside.anStat[0]++;
+        if( db->lookaside.nOut>db->lookaside.mxOut ){
+          db->lookaside.mxOut = db->lookaside.nOut;
+        }
+        return (void*)pBuf;
       }
-      return (void*)pBuf;
     }
   }
 #else

diff --git a/src/sqlite.h.in b/src/sqlite.h.in
index 84999d4b1ad223e547599aef0e83bf42ea187572..226c5f97f5e52c9305b328db460cd0f305fa3a76 100644 (file)
--- a/src/sqlite.h.in
+++ b/src/sqlite.h.in
@@ -5509,6 +5509,28 @@ int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
 ** <dd>This parameter returns the number of lookaside memory slots currently
 ** checked out.</dd>)^
 **
+** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
+** <dd>This parameter returns the number malloc attempts that were 
+** satisfied using lookaside memory. Only the high-water value is meaningful;
+** the current value is always zero.
+** checked out.</dd>)^
+**
+** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
+** <dd>This parameter returns the number malloc attempts that might have
+** been satisfied using lookaside memory but failed due to the amount of
+** memory requested being larger than the lookaside slot size.
+** Only the high-water value is meaningful;
+** the current value is always zero.
+** checked out.</dd>)^
+**
+** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
+** <dd>This parameter returns the number malloc attempts that might have
+** been satisfied using lookaside memory but failed due to all lookaside
+** memory already being in use.
+** Only the high-water value is meaningful;
+** the current value is always zero.
+** checked out.</dd>)^
+**
 ** ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
 ** <dd>This parameter returns the approximate number of of bytes of heap
 ** memory used by all pager caches associated with the database connection.)^
@@ -5531,11 +5553,14 @@ int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
 ** </dd>
 ** </dl>
 */
-#define SQLITE_DBSTATUS_LOOKASIDE_USED     0
-#define SQLITE_DBSTATUS_CACHE_USED         1
-#define SQLITE_DBSTATUS_SCHEMA_USED        2
-#define SQLITE_DBSTATUS_STMT_USED          3
-#define SQLITE_DBSTATUS_MAX                3   /* Largest defined DBSTATUS */
+#define SQLITE_DBSTATUS_LOOKASIDE_USED       0
+#define SQLITE_DBSTATUS_CACHE_USED           1
+#define SQLITE_DBSTATUS_SCHEMA_USED          2
+#define SQLITE_DBSTATUS_STMT_USED            3
+#define SQLITE_DBSTATUS_LOOKASIDE_HIT        4
+#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE  5
+#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL  6
+#define SQLITE_DBSTATUS_MAX                  6   /* Largest defined DBSTATUS */
 
 
 /*

diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 4f0e08ea76dc2c436b2805e00313017afbb1b871..5233e99f09116bb0fac01786d8838effdf02132d 100644 (file)
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -737,6 +737,7 @@ struct Lookaside {
   u8 bMalloced;           /* True if pStart obtained from sqlite3_malloc() */
   int nOut;               /* Number of buffers currently checked out */
   int mxOut;              /* Highwater mark for nOut */
+  int anStat[3];          /* 0: hits.  1: size misses.  2: full misses */
   LookasideSlot *pFree;   /* List of available buffers */
   void *pStart;           /* First byte of available memory space */
   void *pEnd;             /* First byte past end of available space */

diff --git a/src/status.c b/src/status.c
index 7f05f1c68e57a562e39126831497808e57afd166..96759fda7ecc44cfb4e88bc0e4f0d48263199e24 100644 (file)
--- a/src/status.c
+++ b/src/status.c
@@ -116,6 +116,22 @@ int sqlite3_db_status(
       break;
     }
 
+    case SQLITE_DBSTATUS_LOOKASIDE_HIT:
+    case SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE:
+    case SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL: {
+      testcase( op==SQLITE_DBSTATUS_LOOKASIDE_HIT );
+      testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE );
+      testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL );
+      assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)>=0 );
+      assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)<3 );
+      *pCurrent = 0;
+      *pHighwater = db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT];
+      if( resetFlag ){
+        db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT] = 0;
+      }
+      break;
+    }
+
     /* 
     ** Return an approximation for the amount of memory currently used
     ** by all pagers associated with the given database connection.  The