Further enhancements to threadtest3 stress tests.

FossilOrigin-Name: ba772cff602ca7c3c0c91451e701f52a872e7a14

8 files changed, 299 insertions, 60 deletions

diff --git a/manifest b/manifest
index ff005f7ef..d0026036a 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Add\sextra\stests\sto\sthreadtest4.c.\s\sFix\sa\sbenign\sdata\srace\saccessing\sthe\ntext\sencoding\susing\sENC(db).
-D 2014-12-12T23:17:54.003
+C Further\senhancements\sto\sthreadtest3\sstress\stests.
+D 2014-12-13T17:41:48.275
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 6c4f961fa91d0b4fa121946a19f9e5eac2f2f809
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -912,7 +912,7 @@ F test/thread2.test f35d2106452b77523b3a2b7d1dcde2e5ee8f9e46
 F test/thread_common.tcl 334639cadcb9f912bf82aa73f49efd5282e6cadd
 F test/threadtest1.c 6029d9c5567db28e6dc908a0c63099c3ba6c383b
 F test/threadtest2.c ace893054fa134af3fc8d6e7cfecddb8e3acefb9
-F test/threadtest3.c bef2bde18b4e638b6cf4b119aa2076123ffdc425
+F test/threadtest3.c 05d67ab8fd4ad82978a96200701a22af35faa097
 F test/threadtest4.c c1e67136ceb6c7ec8184e56ac61db28f96bd2925
 F test/tkt-02a8e81d44.test 6c80d9c7514e2a42d4918bf87bf6bc54f379110c
 F test/tkt-26ff0c2d1e.test 888324e751512972c6e0d1a09df740d8f5aaf660
@@ -1076,11 +1076,11 @@ F test/triggerB.test 56780c031b454abac2340dbb3b71ac5c56c3d7fe
 F test/triggerC.test a68980c5955d62ee24be6f97129d824f199f9a4c
 F test/triggerD.test 8e7f3921a92a5797d472732108109e44575fa650
 F test/triggerE.test 355e9c5cbaed5cd039a60baad1fb2197caeb8e52
-F test/tt3_checkpoint.c 415eccce672d681b297485fc20f44cdf0eac93af
-F test/tt3_index.c 652630e6b6fc7a48adf2ead60de1ef48e1a34569
-F test/tt3_lookaside1.c 0b5b79ba37f21a1eb849cd4a54eed367f4d4aaaf
-F test/tt3_stress.c e003a8486ba990c43dc9b8298f4b266cd10eb1c1
-F test/tt3_vacuum.c 6a66e52e2b39fc0cccb71db5a302411f34d09736
+F test/tt3_checkpoint.c 5e63ee65ed5f87176e25a996480cb02c6caec8b4
+F test/tt3_index.c 39eec10a35f57672225be4d182862152896dee4a
+F test/tt3_lookaside1.c 0377e202c3c2a50d688cb65ba203afeda6fafeb9
+F test/tt3_stress.c edbb00ed1516535691040315e97cf32c62df22d0
+F test/tt3_vacuum.c 1753f45917699c9c1f66b64c717a717c9379f776
 F test/types.test bf816ce73c7dfcfe26b700c19f97ef4050d194ff
 F test/types2.test 3555aacf8ed8dc883356e59efc314707e6247a84
 F test/types3.test 99e009491a54f4dc02c06bdbc0c5eea56ae3e25a
@@ -1231,7 +1231,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 0abfd78ceb09b7f7c27c688c8e3fe93268a13b32
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P f6bf86f907cbff31bed3cbfc922c10c973575498
-R 97f096b77c750d9e694c3063635e4c8a
-U drh
-Z 4a2c4212438d559f2811b75a6a368836
+P d7bb7ea4ab97ad26f4c84c9b8dc2827010093803
+R 5d62798e848b5017221fa2f718c6fa3d
+U dan
+Z 748bf95122bf9ac21f60dff7348c8009
diff --git a/manifest.uuid b/manifest.uuid
index 2694c2c36..4d5b9316c 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-d7bb7ea4ab97ad26f4c84c9b8dc2827010093803
\ No newline at end of file
+ba772cff602ca7c3c0c91451e701f52a872e7a14
\ No newline at end of file
diff --git a/test/threadtest3.c b/test/threadtest3.c
index 9b12616e3..4cdb0f8e9 100644
--- a/test/threadtest3.c
+++ b/test/threadtest3.c
@@ -47,10 +47,13 @@
 #define execsql_i64(x,y,...)    (SEL(x), execsql_i64_x(x,y,__VA_ARGS__))
 #define execsql_text(x,y,z,...) (SEL(x), execsql_text_x(x,y,z,__VA_ARGS__))
 #define execsql(x,y,...)        (SEL(x), (void)execsql_i64_x(x,y,__VA_ARGS__))
+#define sql_script_printf(x,y,z,...) (                \
+    SEL(x), sql_script_printf_x(x,y,z,__VA_ARGS__)    \
+) 
 
 /* Thread functions */
-#define launch_thread(w,x,y,z)  (SEL(w), launch_thread_x(w,x,y,z))
-#define join_all_threads(y,z)   (SEL(y), join_all_threads_x(y,z))
+#define launch_thread(w,x,y,z)     (SEL(w), launch_thread_x(w,x,y,z))
+#define join_all_threads(y,z)      (SEL(y), join_all_threads_x(y,z))
 
 /* Timer functions */
 #define setstoptime(y,z)        (SEL(y), setstoptime_x(y,z))
@@ -64,6 +67,9 @@
 #define filesize(y,z)           (SEL(y), filesize_x(y,z))
 #define filecopy(x,y,z)         (SEL(x), filecopy_x(x,y,z))
 
+#define PTR2INT(x) ((int)((intptr_t)x))
+#define INT2PTR(x) ((void*)((intptr_t)x))
+
 /*
 ** End of test code/infrastructure interface macros.
 *************************************************************************/
@@ -334,7 +340,7 @@ static void MD5Final(unsigned char digest[16], MD5Context *ctx){
   MD5Transform(ctx->buf, (uint32 *)ctx->in);
   byteReverse((unsigned char *)ctx->buf, 4);
   memcpy(digest, ctx->buf, 16);
-  memset(ctx, 0, sizeof(ctx));    /* In case it is sensitive */
+  memset(ctx, 0, sizeof(*ctx));    /* In case it is sensitive */
 }
 
 /*
@@ -398,9 +404,6 @@ typedef struct Thread Thread;
 /* Total number of errors in this process so far. */
 static int nGlobalErr = 0;
 
-/* Set to true to run in "process" instead of "thread" mode. */
-static int bProcessMode = 0;
-
 struct Error {
   int rc;
   int iLine;
@@ -421,10 +424,10 @@ struct Statement {
 
 struct Thread {
   int iTid;                       /* Thread number within test */
-  int iArg;                       /* Integer argument passed by caller */
+  void* pArg;                     /* Pointer argument passed by caller */
 
   pthread_t tid;                  /* Thread id */
-  char *(*xProc)(int, int);       /* Thread main proc */
+  char *(*xProc)(int, void*);     /* Thread main proc */
   Thread *pNext;                  /* Next in this list of threads */
 };
 
@@ -506,8 +509,9 @@ static void opendb_x(
 ){
   if( pErr->rc==SQLITE_OK ){
     int rc;
+    int flags = SQLITE_OPEN_CREATE | SQLITE_OPEN_READWRITE | SQLITE_OPEN_URI;
     if( bDelete ) unlink(zFile);
-    rc = sqlite3_open(zFile, &pDb->db);
+    rc = sqlite3_open_v2(zFile, &pDb->db, flags, 0);
     if( rc ){
       sqlite_error(pErr, pDb, "open");
       sqlite3_close(pDb->db);
@@ -556,6 +560,22 @@ static void sql_script_x(
   }
 }
 
+static void sql_script_printf_x(
+  Error *pErr,                    /* IN/OUT: Error code */
+  Sqlite *pDb,                    /* Database handle */
+  const char *zFormat,            /* SQL printf format string */
+  ...                             /* Printf args */
+){
+  va_list ap;                     /* ... printf arguments */
+  va_start(ap, zFormat);
+  if( pErr->rc==SQLITE_OK ){
+    char *zSql = sqlite3_vmprintf(zFormat, ap);
+    pErr->rc = sqlite3_exec(pDb->db, zSql, 0, 0, &pErr->zErr);
+    sqlite3_free(zSql);
+  }
+  va_end(ap);
+}
+
 static Statement *getSqlStatement(
   Error *pErr,                    /* IN/OUT: Error code */
   Sqlite *pDb,                    /* Database handle */
@@ -624,11 +644,9 @@ static i64 execsql_i64_x(
   if( pErr->rc==SQLITE_OK ){
     sqlite3_stmt *pStmt;          /* SQL statement to execute */
     va_list ap;                   /* ... arguments */
-    int i;                        /* Used to iterate through parameters */
     va_start(ap, pDb);
     pStmt = getAndBindSqlStatement(pErr, pDb, ap);
     if( pStmt ){
-      int rc;
       int first = 1;
       while( SQLITE_ROW==sqlite3_step(pStmt) ){
         if( first && sqlite3_column_count(pStmt)>0 ){
@@ -663,11 +681,9 @@ static char * execsql_text_x(
   if( pErr->rc==SQLITE_OK ){
     sqlite3_stmt *pStmt;          /* SQL statement to execute */
     va_list ap;                   /* ... arguments */
-    int i;                        /* Used to iterate through parameters */
     va_start(ap, iSlot);
     pStmt = getAndBindSqlStatement(pErr, pDb, ap);
     if( pStmt ){
-      int rc;
       int first = 1;
       while( SQLITE_ROW==sqlite3_step(pStmt) ){
         if( first && sqlite3_column_count(pStmt)>0 ){
@@ -693,14 +709,13 @@ static void integrity_check_x(
 ){
   if( pErr->rc==SQLITE_OK ){
     Statement *pStatement;        /* Statement to execute */
-    int rc;                       /* Return code */
     char *zErr = 0;               /* Integrity check error */
 
     pStatement = getSqlStatement(pErr, pDb, "PRAGMA integrity_check");
     if( pStatement ){
       sqlite3_stmt *pStmt = pStatement->pStmt;
       while( SQLITE_ROW==sqlite3_step(pStmt) ){
-        const char *z = sqlite3_column_text(pStmt, 0);
+        const char *z = (const char*)sqlite3_column_text(pStmt, 0);
         if( strcmp(z, "ok") ){
           if( zErr==0 ){
             zErr = sqlite3_mprintf("%s", z);
@@ -721,14 +736,14 @@ static void integrity_check_x(
 
 static void *launch_thread_main(void *pArg){
   Thread *p = (Thread *)pArg;
-  return (void *)p->xProc(p->iTid, p->iArg);
+  return (void *)p->xProc(p->iTid, p->pArg);
 }
 
 static void launch_thread_x(
   Error *pErr,                    /* IN/OUT: Error code */
   Threadset *pThreads,            /* Thread set */
-  char *(*xProc)(int, int),       /* Proc to run */
-  int iArg                        /* Argument passed to thread proc */
+  char *(*xProc)(int, void*),     /* Proc to run */
+  void *pArg                      /* Argument passed to thread proc */
 ){
   if( pErr->rc==SQLITE_OK ){
     int iTid = ++pThreads->iMaxTid;
@@ -738,7 +753,7 @@ static void launch_thread_x(
     p = (Thread *)sqlite3_malloc(sizeof(Thread));
     memset(p, 0, sizeof(Thread));
     p->iTid = iTid;
-    p->iArg = iArg;
+    p->pArg = pArg;
     p->xProc = xProc;
 
     rc = pthread_create(&p->tid, NULL, launch_thread_main, (void *)p);
@@ -895,7 +910,7 @@ static int timetostop_x(
 #define WALTHREAD1_NTHREAD  10
 #define WALTHREAD3_NTHREAD  6
 
-static char *walthread1_thread(int iTid, int iArg){
+static char *walthread1_thread(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   int nIter = 0;                  /* Iterations so far */
@@ -934,7 +949,7 @@ static char *walthread1_thread(int iTid, int iArg){
   return sqlite3_mprintf("%d iterations", nIter);
 }
 
-static char *walthread1_ckpt_thread(int iTid, int iArg){
+static char *walthread1_ckpt_thread(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   int nCkpt = 0;                  /* Checkpoints so far */
@@ -977,10 +992,11 @@ static void walthread1(int nMs){
   print_and_free_err(&err);
 }
 
-static char *walthread2_thread(int iTid, int iArg){
+static char *walthread2_thread(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   int anTrans[2] = {0, 0};        /* Number of WAL and Rollback transactions */
+  int iArg = PTR2INT(pArg);
 
   const char *zJournal = "PRAGMA journal_mode = WAL";
   if( iArg ){ zJournal = "PRAGMA journal_mode = DELETE"; }
@@ -1026,17 +1042,18 @@ static void walthread2(int nMs){
   setstoptime(&err, nMs);
   launch_thread(&err, &threads, walthread2_thread, 0);
   launch_thread(&err, &threads, walthread2_thread, 0);
-  launch_thread(&err, &threads, walthread2_thread, 1);
-  launch_thread(&err, &threads, walthread2_thread, 1);
+  launch_thread(&err, &threads, walthread2_thread, (void*)1);
+  launch_thread(&err, &threads, walthread2_thread, (void*)1);
   join_all_threads(&err, &threads);
 
   print_and_free_err(&err);
 }
 
-static char *walthread3_thread(int iTid, int iArg){
+static char *walthread3_thread(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   i64 iNextWrite;                 /* Next value this thread will write */
+  int iArg = PTR2INT(pArg);
 
   opendb(&err, &db, "test.db", 0);
   sql_script(&err, &db, "PRAGMA wal_autocheckpoint = 10");
@@ -1087,14 +1104,14 @@ static void walthread3(int nMs){
 
   setstoptime(&err, nMs);
   for(i=0; i<WALTHREAD3_NTHREAD; i++){
-    launch_thread(&err, &threads, walthread3_thread, i);
+    launch_thread(&err, &threads, walthread3_thread, INT2PTR(i));
   }
   join_all_threads(&err, &threads);
 
   print_and_free_err(&err);
 }
 
-static char *walthread4_reader_thread(int iTid, int iArg){
+static char *walthread4_reader_thread(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
 
@@ -1108,7 +1125,7 @@ static char *walthread4_reader_thread(int iTid, int iArg){
   return 0;
 }
 
-static char *walthread4_writer_thread(int iTid, int iArg){
+static char *walthread4_writer_thread(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   i64 iRow = 1;
@@ -1148,7 +1165,7 @@ static void walthread4(int nMs){
   print_and_free_err(&err);
 }
 
-static char *walthread5_thread(int iTid, int iArg){
+static char *walthread5_thread(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   i64 nRow;
@@ -1280,7 +1297,7 @@ static void cgt_pager_1(int nMs){
 **   is an attempt to find a bug reported to us.
 */
 
-static char *dynamic_triggers_1(int iTid, int iArg){
+static char *dynamic_triggers_1(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   int nDrop = 0;
@@ -1331,7 +1348,7 @@ static char *dynamic_triggers_1(int iTid, int iArg){
   return sqlite3_mprintf("%d created, %d dropped", nCreate, nDrop);
 }
 
-static char *dynamic_triggers_2(int iTid, int iArg){
+static char *dynamic_triggers_2(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   i64 iVal = 0;
@@ -1382,9 +1399,9 @@ static void dynamic_triggers(int nMs){
   sqlite3_enable_shared_cache(1);
   launch_thread(&err, &threads, dynamic_triggers_2, 0);
   launch_thread(&err, &threads, dynamic_triggers_2, 0);
-  sqlite3_enable_shared_cache(0);
 
   sleep(2);
+  sqlite3_enable_shared_cache(0);
 
   launch_thread(&err, &threads, dynamic_triggers_2, 0);
   launch_thread(&err, &threads, dynamic_triggers_1, 0);
@@ -1425,6 +1442,7 @@ int main(int argc, char **argv){
     { lookaside1,          "lookaside1", 10000 },
     { vacuum1,             "vacuum1", 10000 },
     { stress1,             "stress1", 10000 },
+    { stress2,             "stress2", 10000 },
   };
 
   int i;
@@ -1444,6 +1462,7 @@ int main(int argc, char **argv){
   }
 
   sqlite3_config(SQLITE_CONFIG_MULTITHREAD);
+  sqlite3_config(SQLITE_CONFIG_MULTITHREAD);
 
   for(i=0; i<sizeof(aTest)/sizeof(aTest[0]); i++){
     char const *z = aTest[i].zTest;
diff --git a/test/tt3_checkpoint.c b/test/tt3_checkpoint.c
index 3c28f0d3a..db237d6d9 100644
--- a/test/tt3_checkpoint.c
+++ b/test/tt3_checkpoint.c
@@ -66,7 +66,7 @@ static int checkpoint_starvation_walhook(
   return SQLITE_OK;
 }
 
-static char *checkpoint_starvation_reader(int iTid, int iArg){
+static char *checkpoint_starvation_reader(int iTid, void *pArg){
   Error err = {0};
   Sqlite db = {0};
 
diff --git a/test/tt3_index.c b/test/tt3_index.c
index 2445f398c..62f06ade4 100644
--- a/test/tt3_index.c
+++ b/test/tt3_index.c
@@ -14,7 +14,7 @@
 */
 
 
-static char *create_drop_index_thread(int iTid, int iArg){
+static char *create_drop_index_thread(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
 
diff --git a/test/tt3_lookaside1.c b/test/tt3_lookaside1.c
index 486de808c..e785e7998 100644
--- a/test/tt3_lookaside1.c
+++ b/test/tt3_lookaside1.c
@@ -18,7 +18,7 @@
 ** that is suspected to exist at time of writing.
 */
 
-static char *lookaside1_thread_reader(int iTid, int iArg){
+static char *lookaside1_thread_reader(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
 
@@ -43,7 +43,7 @@ static char *lookaside1_thread_reader(int iTid, int iArg){
   return sqlite3_mprintf("ok");
 }
 
-static char *lookaside1_thread_writer(int iTid, int iArg){
+static char *lookaside1_thread_writer(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
 
diff --git a/test/tt3_stress.c b/test/tt3_stress.c
index 93a0d0aa1..a1151dd79 100644
--- a/test/tt3_stress.c
+++ b/test/tt3_stress.c
@@ -17,7 +17,7 @@
 /*
 ** Thread 1. CREATE and DROP a table.
 */
-static char *stress_thread_1(int iTid, int iArg){
+static char *stress_thread_1(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
 
@@ -36,7 +36,7 @@ static char *stress_thread_1(int iTid, int iArg){
 /*
 ** Thread 2. Open and close database connections.
 */
-static char *stress_thread_2(int iTid, int iArg){
+static char *stress_thread_2(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   while( !timetostop(&err) ){
@@ -52,7 +52,7 @@ static char *stress_thread_2(int iTid, int iArg){
 /*
 ** Thread 3. Attempt many small SELECT statements.
 */
-static char *stress_thread_3(int iTid, int iArg){
+static char *stress_thread_3(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
 
@@ -75,11 +75,13 @@ static char *stress_thread_3(int iTid, int iArg){
 /*
 ** Thread 5. Attempt INSERT statements.
 */
-static char *stress_thread_4(int iTid, int iArg){
+static char *stress_thread_4(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   int i1 = 0;
   int i2 = 0;
+  int iArg = PTR2INT(pArg);
+
   opendb(&err, &db, "test.db", 0);
   while( !timetostop(&err) ){
     if( iArg ){
@@ -103,9 +105,10 @@ static char *stress_thread_4(int iTid, int iArg){
 /*
 ** Thread 6. Attempt DELETE operations.
 */
-static char *stress_thread_5(int iTid, int iArg){
+static char *stress_thread_5(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
+  int iArg = PTR2INT(pArg);
 
   int i1 = 0;
   int i2 = 0;
@@ -131,12 +134,9 @@ static char *stress_thread_5(int iTid, int iArg){
 
 static void stress1(int nMs){
   Error err = {0};
-  Sqlite db = {0};
   Threadset threads = {0};
 
-
   setstoptime(&err, nMs);
-
   sqlite3_enable_shared_cache(1);
 
   launch_thread(&err, &threads, stress_thread_1, 0);
@@ -152,10 +152,230 @@ static void stress1(int nMs){
   launch_thread(&err, &threads, stress_thread_4, 0);
 
   launch_thread(&err, &threads, stress_thread_5, 0);
-  launch_thread(&err, &threads, stress_thread_5, 1);
+  launch_thread(&err, &threads, stress_thread_5, (void*)1);
 
   join_all_threads(&err, &threads);
   sqlite3_enable_shared_cache(0);
 
   print_and_free_err(&err);
 }
+
+/**************************************************************************
+***************************************************************************
+** Start of test case "stress2"
+*/
+
+
+
+/*
+** 1.  CREATE TABLE statements.
+** 2.  DROP TABLE statements.
+** 3.  Small SELECT statements.
+** 4.  Big SELECT statements.
+** 5.  Small INSERT statements.
+** 6.  Big INSERT statements.
+** 7.  Small UPDATE statements.
+** 8.  Big UPDATE statements.
+** 9.  Small DELETE statements.
+** 10. Big DELETE statements.
+** 11. VACUUM.
+** 14. Integrity-check.
+** 17. Switch the journal mode from delete to wal and back again.
+** 19. Open and close database connections rapidly.
+*/
+
+#define STRESS2_TABCNT 5
+
+static void stress2_workload1(Error *pErr, Sqlite *pDb, int i){
+  int iTab = (i % STRESS2_TABCNT);
+  sql_script_printf(pErr, pDb, 
+      "CREATE TABLE IF NOT EXISTS t%d(x PRIMARY KEY, y, z);", iTab
+  );
+}
+
+static void stress2_workload2(Error *pErr, Sqlite *pDb, int i){
+  int iTab = (i % STRESS2_TABCNT);
+  sql_script_printf(pErr, pDb, "DROP TABLE IF EXISTS t%d;", iTab);
+}
+
+static void stress2_workload3(Error *pErr, Sqlite *pDb, int i){
+  int iTab = (i % STRESS2_TABCNT);
+  sql_script_printf(pErr, pDb, "SELECT * FROM t%d WHERE z = 'small'", iTab);
+}
+
+static void stress2_workload4(Error *pErr, Sqlite *pDb, int i){
+  int iTab = (i % STRESS2_TABCNT);
+  sql_script_printf(pErr, pDb, "SELECT * FROM t%d WHERE z = 'big'", iTab);
+}
+
+static void stress2_workload5(Error *pErr, Sqlite *pDb, int i){
+  int iTab = (i % STRESS2_TABCNT);
+  sql_script_printf(pErr, pDb,
+      "INSERT INTO t%d VALUES(random(), hex(randomblob(57)), 'small');", iTab
+  );
+}
+
+static void stress2_workload6(Error *pErr, Sqlite *pDb, int i){
+  int iTab = (i % STRESS2_TABCNT);
+  sql_script_printf(pErr, pDb,
+      "INSERT INTO t%d VALUES(random(), hex(randomblob(2000)), 'big');", iTab
+  );
+}
+
+static void stress2_workload7(Error *pErr, Sqlite *pDb, int i){
+  int iTab = (i % STRESS2_TABCNT);
+  sql_script_printf(pErr, pDb,
+      "UPDATE t%d SET y = hex(randomblob(57)) "
+      "WHERE (x %% 5)==(%d %% 5) AND z='small';"
+      ,iTab, i
+  );
+}
+static void stress2_workload8(Error *pErr, Sqlite *pDb, int i){
+  int iTab = (i % STRESS2_TABCNT);
+  sql_script_printf(pErr, pDb,
+      "UPDATE t%d SET y = hex(randomblob(2000)) "
+      "WHERE (x %% 5)==(%d %% 5) AND z='big';"
+      ,iTab, i
+  );
+}
+
+static void stress2_workload9(Error *pErr, Sqlite *pDb, int i){
+  int iTab = (i % STRESS2_TABCNT);
+  sql_script_printf(pErr, pDb,
+      "DELETE FROM t%d WHERE (x %% 5)==(%d %% 5) AND z='small';"
+      ,iTab, i
+  );
+}
+static void stress2_workload10(Error *pErr, Sqlite *pDb, int i){
+  int iTab = (i % STRESS2_TABCNT);
+  sql_script_printf(pErr, pDb,
+      "DELETE FROM t%d WHERE (x %% 5)==(%d %% 5) AND z='big';"
+      ,iTab, i
+  );
+}
+
+static void stress2_workload11(Error *pErr, Sqlite *pDb, int i){
+  sql_script(pErr, pDb, "VACUUM");
+}
+
+static void stress2_workload14(Error *pErr, Sqlite *pDb, int i){
+  sql_script(pErr, pDb, "PRAGMA integrity_check");
+}
+
+static void stress2_workload17(Error *pErr, Sqlite *pDb, int i){
+  sql_script_printf(pErr, pDb, 
+      "PRAGMA journal_mode = %q", (i%2) ? "delete" : "wal"
+  );
+}
+
+static char *stress2_workload19(int iTid, void *pArg){
+  Error err = {0};                /* Error code and message */
+  Sqlite db = {0};                /* SQLite database connection */
+  const char *zDb = (const char*)pArg;
+  while( !timetostop(&err) ){
+    opendb(&err, &db, zDb, 0);
+    sql_script(&err, &db, "SELECT * FROM sqlite_master;");
+    clear_error(&err, SQLITE_LOCKED);
+    closedb(&err, &db);
+  }
+  print_and_free_err(&err);
+  return sqlite3_mprintf("ok");
+}
+
+
+typedef struct Stress2Ctx Stress2Ctx;
+struct Stress2Ctx {
+  const char *zDb;
+  void (*xProc)(Error*, Sqlite*, int);
+};
+
+static char *stress2_thread_wrapper(int iTid, void *pArg){
+  Stress2Ctx *pCtx = (Stress2Ctx*)pArg;
+  Error err = {0};                /* Error code and message */
+  Sqlite db = {0};                /* SQLite database connection */
+  int i1 = 0;
+  int i2 = 0;
+
+  opendb(&err, &db, pCtx->zDb, 0);
+  while( !timetostop(&err) ){
+    pCtx->xProc(&err, &db, i1);
+    i2 += (err.rc==SQLITE_OK);
+    clear_error(&err, SQLITE_LOCKED);
+    clear_error(&err, SQLITE_ERROR);
+    i1++;
+  }
+
+  print_and_free_err(&err);
+  return sqlite3_mprintf("ok %d/%d", i2, i1);
+}
+
+static void stress2_launch_thread_loop(
+  Error *pErr,                    /* IN/OUT: Error code */
+  Threadset *pThreads,            /* Thread set */
+  const char *zDb,                /* Database name */
+  void (*x)(Error*,Sqlite*,int)   /* Run this until error or timeout */
+){
+  Stress2Ctx *pCtx = sqlite3_malloc(sizeof(Stress2Ctx));
+  pCtx->zDb = zDb;
+  pCtx->xProc = x;
+  launch_thread(pErr, pThreads, stress2_thread_wrapper, (void*)pCtx);
+}
+
+static void stress2(int nMs){
+  struct Stress2Task {
+    void (*x)(Error*,Sqlite*,int);
+  } aTask[] = {
+    { stress2_workload1 },
+    { stress2_workload2 },
+    { stress2_workload3 },
+    { stress2_workload4 },
+    { stress2_workload5 },
+    { stress2_workload6 },
+    { stress2_workload7 },
+    { stress2_workload8 },
+    { stress2_workload9 },
+    { stress2_workload10 },
+    { stress2_workload11 },
+    { stress2_workload14 },
+    { stress2_workload17 },
+  };
+  const char *azDb[] = {
+    "test.db",
+    "file::memory:?cache=shared"
+  };
+  int j;
+
+  for(j=0; j<sizeof(azDb)/sizeof(azDb[0]); j++){
+    int i;
+    Error err = {0};
+    Sqlite db = {0};
+    Threadset threads = {0};
+    const char *zDb = azDb[j];
+
+    /* To make sure the db file is empty before commencing */
+    opendb(&err, &db, zDb, 1);
+    closedb(&err, &db);
+
+    setstoptime(&err, nMs);
+    sqlite3_enable_shared_cache(1);
+
+    for(i=0; i<sizeof(aTask)/sizeof(aTask[0]); i++){
+      stress2_launch_thread_loop(&err, &threads, zDb, aTask[i].x);
+    }
+    launch_thread(&err, &threads, stress2_workload19, (void*)zDb);
+    launch_thread(&err, &threads, stress2_workload19, (void*)zDb);
+
+    join_all_threads(&err, &threads);
+    sqlite3_enable_shared_cache(0);
+    print_and_free_err(&err);
+    if( j==0 ){
+      printf("Running stress2 (again, with in-memory db) for %d seconds...\n",
+          nMs / 1000
+      );
+    }
+  }
+}
+
+
+
+
diff --git a/test/tt3_vacuum.c b/test/tt3_vacuum.c
index 126bbfc26..023fdfd74 100644
--- a/test/tt3_vacuum.c
+++ b/test/tt3_vacuum.c
@@ -20,7 +20,7 @@
 */
 
 
-static char *vacuum1_thread_writer(int iTid, int iArg){
+static char *vacuum1_thread_writer(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   opendb(&err, &db, "test.db", 0);
@@ -49,7 +49,7 @@ static char *vacuum1_thread_writer(int iTid, int iArg){
   return sqlite3_mprintf("ok");
 }
 
-static char *vacuum1_thread_vacuumer(int iTid, int iArg){
+static char *vacuum1_thread_vacuumer(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   opendb(&err, &db, "test.db", 0);