Change the btree node balancers to sort nodes into accending order. This

improves insert and delete speed by 25%. (CVS 409)

FossilOrigin-Name: abbb999d4fc3fe142567b6ede5e625e7bf0da714

diff --git a/manifest b/manifest
index b0ea0909d958662890206c81d6cc0335862592ad..ae177e5f97f341f1cb2d04bbfe42b057ec8099af 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Subquery\sflattening\sis\simplemented\sand\spasses\sall\sregression\stests.\nWe\sstill\sneed\sto\sadd\saddition\stests\sto\sthe\ssuite\sto\sfurther\sexercise\nthe\sflattener,\showever.\s(CVS\s408)
-D 2002-03-02T17:04:08
+C Change\sthe\sbtree\snode\sbalancers\sto\ssort\snodes\sinto\saccending\sorder.\s\sThis\nimproves\sinsert\sand\sdelete\sspeed\sby\s25%.\s(CVS\s409)
+D 2002-03-02T19:00:31
 F Makefile.in 50f1b3351df109b5774771350d8c1b8d3640130d
 F Makefile.template 89e373b2dad0321df00400fa968dc14b61a03296
 F README a4c0ba11354ef6ba0776b400d057c59da47a4cc0
@@ -19,12 +19,12 @@ F ltmain.sh e9ed72eb1d690f447c13945eaf69e28af531eda1
 F publish.sh 5b59f4aff037aafa0e4a3b6fa599495dbd73f360
 F sqlite.1 2e2bb0529ef468ade9e4322bd609d0695fb9ded9
 F src/TODO af7f3cab0228e34149cf98e073aa83d45878e7e6
-F src/btree.c 495275fe14f3b718cf2f691dce979d4c0e1f8e5d
+F src/btree.c 360c0aa4db058bd2d33269d7416178bdc7b7fe41
 F src/btree.h 8abeabfe6e0b1a990b64fa457592a6482f6674f3
 F src/build.c 2f6d3136e6b824b2b446c54db2d2be5703033203
 F src/delete.c bf569eeb66dc851966b5681e5154d5fe2aee92c2
 F src/expr.c 17e3db6f115d60530a55530e3046312196c5eb36
-F src/func.c 0db438ba17f3394dc5a3ffcd2ee41ca0c8e80b21
+F src/func.c 5b4d9707b0c8f463824c1f04547b524cba24bf7b
 F src/hash.c cc259475e358baaf299b00a2c7370f2b03dda892
 F src/hash.h dca065dda89d4575f3176e75e9a3dc0f4b4fb8b9
 F src/insert.c 4fb3428f591afe106f6e60029a61f87fa0e79920
@@ -127,7 +127,7 @@ F www/speed.tcl 83457b2bf6bb430900bd48ca3dd98264d9a916a5
 F www/sqlite.tcl 8b5884354cb615049aed83039f8dfe1552a44279
 F www/tclsqlite.tcl 829b393d1ab187fd7a5e978631b3429318885c49
 F www/vdbe.tcl 2013852c27a02a091d39a766bc87cff329f21218
-P e14b0c82f3514f41934a7c0d173b6fdb186aafc8
-R f60c0ec90c7ca3b07c137c446692b495
+P d5d3e79cc58da5bd315cc1fea1f7cbf46274da16
+R e2a0844c770bfd758020b0af68cec917
 U drh
-Z 28d7598277d139ff75ed8a6bf05f4a82
+Z fff6edd2a1ed34d852214cfe902efd49

diff --git a/manifest.uuid b/manifest.uuid
index 7018ef2a6c2c2ed61e7609a832ffea486a539b81..6165d4720a0f4e0a5503ef2410bbd572d5eb2b47 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-d5d3e79cc58da5bd315cc1fea1f7cbf46274da16
\ No newline at end of file
+abbb999d4fc3fe142567b6ede5e625e7bf0da714
\ No newline at end of file

diff --git a/src/btree.c b/src/btree.c
index ddf9edf197864a94803293b1f29e5835d794cdb1..5d591f15047c387cf282f45fe038130f8b654f68 100644 (file)
--- a/src/btree.c
+++ b/src/btree.c
@@ -9,7 +9,7 @@
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** $Id: btree.c,v 1.55 2002/02/19 22:43:59 drh Exp $
+** $Id: btree.c,v 1.56 2002/03/02 19:00:31 drh Exp $
 **
 ** This file implements a external (disk-based) database using BTrees.
 ** For a detailed discussion of BTrees, refer to
@@ -2104,6 +2104,40 @@ static int balance(Btree *pBt, MemPage *pPage, BtCursor *pCur){
     apNew[i]->isInit = 1;
   }
 
+  /*
+  ** Put the new pages in accending order.  This helps to
+  ** keep entries in the disk file in order so that a scan
+  ** of the table is a linear scan through the file.  That
+  ** in turn helps the operating system to deliver pages
+  ** from the disk more rapidly.
+  **
+  ** An O(n^2) insertion sort algorithm is used, but since
+  ** n is never more than 3, that should not be a problem.
+  **
+  ** This one optimization makes the database about 25%
+  ** faster for large insertions and deletions.
+  */
+  for(i=0; i<k-1; i++){
+    int minV = pgnoNew[i];
+    int minI = i;
+    for(j=i+1; j<k; j++){
+      if( pgnoNew[j]<minV ){
+        minI = j;
+        minV = pgnoNew[j];
+      }
+    }
+    if( minI>i ){
+      int t;
+      MemPage *pT;
+      t = pgnoNew[i];
+      pT = apNew[i];
+      pgnoNew[i] = pgnoNew[minI];
+      apNew[i] = apNew[minI];
+      pgnoNew[minI] = t;
+      apNew[minI] = pT;
+    }
+  }
+
   /*
   ** Evenly distribute the data in apCell[] across the new pages.
   ** Insert divider cells into pParent as necessary.

diff --git a/src/func.c b/src/func.c
index e995842018fdd25a3f82198734004713fe64fff1..304d828e6210d18d67cc34ee77f9e8cb2c486222 100644 (file)
--- a/src/func.c
+++ b/src/func.c
@@ -16,7 +16,7 @@
 ** sqliteRegisterBuildinFunctions() found at the bottom of the file.
 ** All other code has file scope.
 **
-** $Id: func.c,v 1.12 2002/02/28 04:00:12 drh Exp $
+** $Id: func.c,v 1.13 2002/03/02 19:00:31 drh Exp $
 */
 #include <ctype.h>
 #include <math.h>
@@ -189,6 +189,13 @@ static void ifnullFunc(sqlite_func *context, int argc, const char **argv){
   }
 }
 
+/*
+** Implementation of random().  Return a random integer.  
+*/
+static void randomFunc(sqlite_func *context, int argc, const char **argv){
+  sqlite_set_result_int(context, sqliteRandomInteger());
+}
+
 /*
 ** An instance of the following structure holds the context of a
 ** sum() or avg() aggregate computation.
@@ -375,7 +382,7 @@ void sqliteRegisterBuildinFunctions(sqlite *db){
     { "coalesce",  -1, ifnullFunc },
     { "coalesce",   0, 0          },
     { "coalesce",   1, 0          },
-
+    { "random",    -1, randomFunc },
   };
   static struct {
     char *zName;