This hack illustrates how to use the VDBE_PROFILE mechanism to show which

bytecode operators are using resources other than time.  In this case, the
number of loops through the binary search code in sqlite3BtreeMovetoUnpacked()
is measured, for the purpose of helping to identify unnecessary btree searches.

FossilOrigin-Name: 746b1836834914627d97369690b9596d80235a35

manifest

@@ -1,5 +1,5 @@
-C Ensure\sthat\s"PRAGMA\scase_sensitive_like"\sand\s"PRAGMA\sshrink_memory"\sset\sthe\nnumber\sof\soutput\scolumns\sto\s0\s(as\sthey\sare\sstatements\sthat\sreturn\sno\sdata).
-D 2017-01-06T13:49:40.112
+C This\shack\sillustrates\show\sto\suse\sthe\sVDBE_PROFILE\smechanism\sto\sshow\swhich\nbytecode\soperators\sare\susing\sresources\sother\sthan\stime.\s\sIn\sthis\scase,\sthe\nnumber\sof\sloops\sthrough\sthe\sbinary\ssearch\scode\sin\ssqlite3BtreeMovetoUnpacked()\nis\smeasured,\sfor\sthe\spurpose\sof\shelping\sto\sidentify\sunnecessary\sbtree\ssearches.
+D 2017-01-07T00:42:57.449
 F Makefile.in 41bd4cad981487345c4a84081074bcdb876e4b2e
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc b8ca53350ae545e3562403d5da2a69cec79308da
@@ -331,7 +331,7 @@ F src/auth.c 930b376a9c56998557367e6f7f8aaeac82a2a792
 F src/backup.c faf17e60b43233c214aae6a8179d24503a61e83b
 F src/bitvec.c 17ea48eff8ba979f1f5b04cc484c7bb2be632f33
 F src/btmutex.c 0e9ce2d56159b89b9bc8e197e023ee11e39ff8ca
-F src/btree.c d2c100618784bd89c089fcef03ff6e789768ecae
+F src/btree.c 616212acc17a89d835fb5a9d379881af42485790
 F src/btree.h 2349a588abcd7e0c04f984e15c5c777b61637583
 F src/btreeInt.h 10c4b77c2fb399580babbcc7cf652ac10dba796e
 F src/build.c 9e799f1edd910dfa8a0bc29bd390d35d310596af
@@ -393,7 +393,7 @@ F src/shell.c 6095531aa900decdaa765e0f3993fba7153c92c1
 F src/sqlite.h.in 29bda4bee01248a5650567d7a22fac39bad1b542
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 8648034aa702469afb553231677306cc6492a1ae
-F src/sqliteInt.h 9fdfb8789b27a621f3401468bc1705c32308f877
+F src/sqliteInt.h 44a74e425b9e4a88b15e3ece325a0c03f74ce715
 F src/sqliteLimit.h c0373387c287c8d0932510b5547ecde31b5da247
 F src/status.c a9e66593dfb28a9e746cba7153f84d49c1ddc4b1
 F src/table.c 5226df15ab9179b9ed558d89575ea0ce37b03fc9
@@ -455,7 +455,7 @@ F src/update.c 1da7c462110bffed442a42884cb0d528c1db46d8
 F src/utf.c 699001c79f28e48e9bcdf8a463da029ea660540c
 F src/util.c a88b0466fddf445ce752226d4698ca3faada620a
 F src/vacuum.c 33c174b28886b2faf26e503b5a49a1c01a9b1c16
-F src/vdbe.c 88bd6c32b333580d2661ac3afe33369757fb1522
+F src/vdbe.c 2d97b1955677d059ed0fbb70edbd6caa356a827d
 F src/vdbe.h b0866e4191f096f1c987a84b042c3599bdf5423b
 F src/vdbeInt.h 281cb70332dc8b593b8c7afe776f3a2ba7d4255e
 F src/vdbeapi.c d6ebaa465f070eb1af8ba4e7b34583ece87bdd24
@@ -1543,7 +1543,10 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 609ac1c73f7c2b48a571c178a72383996a9538fe
-R 812971df62a9791f0bfb0122470a2213
-U dan
-Z ebefd6b7654323e8a23a6cf648753c0a
+P 6696cd1878be4bd44a24841b04163e52d847711e
+R 84e708f4e891dde33f19bfdca19817dd
+T *branch * vdbe-aux-perf
+T *sym-vdbe-aux-perf *
+T -sym-trunk *
+U drh
+Z de29ad8a6d413bf4c57cf80372a53ca1

manifest.uuid

@@ -1 +1 @@
-6696cd1878be4bd44a24841b04163e52d847711e
+746b1836834914627d97369690b9596d80235a35

src/btree.c

@@ -5124,6 +5124,7 @@ int sqlite3BtreeMovetoUnpacked(
     Pgno chldPg;
     MemPage *pPage = pCur->apPage[pCur->iPage];
     u8 *pCell;                          /* Pointer to current cell in pPage */
+sqlite3PerfCnt++;
 
     /* pPage->nCell must be greater than zero. If this is the root-page
     ** the cursor would have been INVALID above and this for(;;) loop

src/sqliteInt.h

@@ -4321,4 +4321,6 @@ Expr *sqlite3VectorFieldSubexpr(Expr*, int);
 Expr *sqlite3ExprForVectorField(Parse*,Expr*,int);
 void sqlite3VectorErrorMsg(Parse*, Expr*);
 
+sqlite3_uint64 sqlite3PerfCnt;
+
 #endif /* SQLITEINT_H */

src/vdbe.c

@@ -506,7 +506,8 @@ static void registerTrace(int iReg, Mem *p){
 ** hwtime.h contains inline assembler code for implementing 
 ** high-performance timing routines.
 */
-#include "hwtime.h"
+/*#include "hwtime.h"*/
+#define sqlite3Hwtime(x) sqlite3PerfCnt
 
 #endif