Fix a race condition in the sorter.

FossilOrigin-Name: 32ccf3ae18531682dfd039fa8df6ad9a907ac455

diff --git a/manifest b/manifest
index 53d89eafaf74a40ecbcdaee6bf1e5591099f9964..917d67a6b3ef3c54919f6a04b758c6744e3cb8f7 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sa\sproblem\sin\sthe\ssorter\scausing\sit\sto\sreturn\sspurious\sSQLITE_NOMEM\serrors\swhen\sconfigured\sto\suse\smemsys3\sor\smemsys5.
-D 2014-05-03T14:28:14.676
+C Fix\sa\srace\scondition\sin\sthe\ssorter.
+D 2014-05-03T19:33:00.713
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in ad0921c4b2780d01868cf69b419a4f102308d125
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -287,7 +287,7 @@ F src/vdbeapi.c 0ed6053f947edd0b30f64ce5aeb811872a3450a4
 F src/vdbeaux.c 44d4d1f5711f71eaf0d624de5c3e4976fe4e180b
 F src/vdbeblob.c 9205ce9d3b064d9600f8418a897fc88b5687d9ac
 F src/vdbemem.c 6fc77594c60f6155404f3f8d71bf36d1fdeb4447
-F src/vdbesort.c 3e8827bb9d12465556357c24641f8805a7e2bba0
+F src/vdbesort.c c443cdf00fc8b90b17fbeaa1ad833d3091b0bf5c
 F src/vdbetrace.c 6f52bc0c51e144b7efdcfb2a8f771167a8816767
 F src/vtab.c 21b932841e51ebd7d075e2d0ad1415dce8d2d5fd
 F src/wal.c 76e7fc6de229bea8b30bb2539110f03a494dc3a8
@@ -821,10 +821,10 @@ F test/skipscan1.test bed8cbe9d554c8c27afb6c88500f704c86a9196f
 F test/skipscan2.test d77f79cdbba25f0f6f35298136cff21a7d7a553a
 F test/soak.test 0b5b6375c9f4110c828070b826b3b4b0bb65cd5f
 F test/softheap1.test 40562fe6cac6d9827b7b42b86d45aedf12c15e24
-F test/sort.test 8330b31b160483b52bb502a3ac4013f3f9028d73
+F test/sort.test 2af626b7963eddb8c93b6c87babf81396c379ef5
 F test/sort2.test c5e25eb674689e291d06b5209fe8d337ae0ec010
 F test/sort3.test 6178ade30810ac9166fcdf14b7065e49c0f534e2
-F test/sortfault.test 7fdc4a9bd76280a659c5782cdc6d95806d62d512
+F test/sortfault.test f875d29c58b2eafdca1b51c0810075570d5a3cbc
 F test/speed1.test f2974a91d79f58507ada01864c0e323093065452
 F test/speed1p.explain d841e650a04728b39e6740296b852dccdca9b2cb
 F test/speed1p.test b180e98609c7677382cf618c0ec9b69f789033a8
@@ -1170,7 +1170,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh d1a6de74685f360ab718efda6265994b99bbea01
 F tool/win/sqlite.vsix 030f3eeaf2cb811a3692ab9c14d021a75ce41fff
-P f49ba1c926c63ee1c4609930138389fca182c845
-R ecf8f8bb6befc88e6cfdbe14a65100aa
+P 3a66c4e1bf311d38668dfcdcd77867feff6db7bd
+R 07ad433b1f531db0a3f09b334b377488
 U dan
-Z 4d5ad6cf671998327bccef4dcd098843
+Z 8b4c7c15ef224489143b17033ef5ced9

diff --git a/manifest.uuid b/manifest.uuid
index 500fa40c2b5f36eabe25fd60530e6c0bb5d9d8e5..6bfb75656cc1eaaba161895513d04fe2fc5ef909 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-3a66c4e1bf311d38668dfcdcd77867feff6db7bd
\ No newline at end of file
+32ccf3ae18531682dfd039fa8df6ad9a907ac455
\ No newline at end of file

diff --git a/src/vdbesort.c b/src/vdbesort.c
index 5efd6f112c2ed507cf3605e9df0256e6437a440c..5676d96e3781d0f8ab33218d5c72bbebbcc9f76a 100644 (file)
--- a/src/vdbesort.c
+++ b/src/vdbesort.c
@@ -651,6 +651,7 @@ static int vdbePmaReaderNext(PmaReader *pIter){
   int rc = SQLITE_OK;             /* Return Code */
   u64 nRec = 0;                   /* Size of record in bytes */
 
+
   if( pIter->iReadOff>=pIter->iEof ){
     IncrMerger *pIncr = pIter->pIncr;
     int bEof = 1;
@@ -1844,10 +1845,18 @@ static int vdbeIncrInitMerger(
 ){
   int rc = SQLITE_OK;             /* Return code */
   int i;                          /* For iterating through PmaReader objects */
+  int nTree = pMerger->nTree;
 
-  for(i=0; rc==SQLITE_OK && i<pMerger->nTree; i++){
+  for(i=0; rc==SQLITE_OK && i<nTree; i++){
     if( eMode==INCRINIT_ROOT ){
-      rc = vdbePmaReaderNext(&pMerger->aIter[i]);
+      /* Iterators should be normally initialized in order, as if they are
+      ** reading from the same temp file this makes for more linear file IO.
+      ** However, in the INCRINIT_ROOT case, if iterator aIter[nTask-1] is
+      ** in use it will block the vdbePmaReaderNext() call while it uses
+      ** the main thread to fill its buffer. So calling PmaReaderNext()
+      ** on this iterator before any of the multi-threaded iterators takes
+      ** better advantage of multi-processor hardware. */
+      rc = vdbePmaReaderNext(&pMerger->aIter[nTree-i-1]);
     }else{
       rc = vdbePmaReaderIncrInit(&pMerger->aIter[i], INCRINIT_NORMAL);
     }
@@ -2196,7 +2205,13 @@ static int vdbeSorterSetupMerge(VdbeSorter *pSorter){
             for(iTask=0; rc==SQLITE_OK && iTask<pSorter->nTask; iTask++){
               PmaReader *p = &pMain->aIter[iTask];
               assert( p->pIncr==0 || p->pIncr->pTask==&pSorter->aTask[iTask] );
-              if( p->pIncr ){ rc = vdbePmaReaderBgIncrInit(p); }
+              if( p->pIncr ){ 
+                if( iTask==pSorter->nTask-1 ){
+                  rc = vdbePmaReaderIncrInit(p, INCRINIT_TASK);
+                }else{
+                  rc = vdbePmaReaderBgIncrInit(p);
+                }
+              }
             }
           }
         }

diff --git a/test/sort.test b/test/sort.test
index c6c7fc6e410a31f671c1695e32bc2f0d14526885..0c87dd64414db070635dfc3467ffeff0f4ee1572 100644 (file)
--- a/test/sort.test
+++ b/test/sort.test
@@ -541,7 +541,6 @@ foreach {tn mmap_limit nWorker tmpstore coremutex fakeheap} {
           5          0       0   memory     false     true
 } {
   db close
-
   sqlite3_shutdown
   sqlite3_config_worker_threads $nWorker
   if {$coremutex} {
@@ -550,7 +549,6 @@ foreach {tn mmap_limit nWorker tmpstore coremutex fakeheap} {
     sqlite3_config singlethread
   }
   sqlite3_initialize
-
   sorter_test_fakeheap $fakeheap
 
   reset_db
@@ -597,7 +595,6 @@ foreach {tn mmap_limit nWorker tmpstore coremutex fakeheap} {
 
 db close
 sqlite3_shutdown
-#sqlite3_config_worker_threads $sqlite_options(worker_threads)
 sqlite3_config_worker_threads 0
 set t(0) singlethread
 set t(1) multithread

diff --git a/test/sortfault.test b/test/sortfault.test
index abe9af6854e9b8a1db5d0c7ad65adf812446a2f0..7c58bb683301a6cdc4ec2eb03fcca676942e0b7c 100644 (file)
--- a/test/sortfault.test
+++ b/test/sortfault.test
@@ -23,27 +23,45 @@ do_execsql_test 1.0 {
   PRAGMA cache_size = 5;
 }
 
-foreach {tn mmap_limit} {
-  1 0
-  2 100000
+foreach {tn mmap_limit nWorker tmpstore threadsmode fakeheap} {
+          1          0       0     file multithread    false
+          2     100000       0     file multithread    false
 } {
+  catch { db close }
+  sqlite3_shutdown
+  sqlite3_config_worker_threads $nWorker
+  sqlite3_config $threadsmode
+  sqlite3_initialize
+  sorter_test_fakeheap $fakeheap
+
+  set str [string repeat a 1000]
+
   do_faultsim_test 1.$tn -prep {
     sqlite3 db test.db
     sqlite3_test_control SQLITE_TESTCTRL_SORTER_MMAP db $::mmap_limit
+    execsql { PRAGMA cache_size = 5 }
   } -body {
     execsql { 
       WITH r(x,y) AS (
-          SELECT 1, randomblob(1000)
+          SELECT 1, $::str
           UNION ALL
-          SELECT x+1, randomblob(1000) FROM r
-          LIMIT 500
-          )
-        SELECT count(x), length(y) FROM r GROUP BY (x%5)
-    } 
+          SELECT x+1, $::str FROM r
+          LIMIT 200
+      )
+      SELECT count(x), length(y) FROM r GROUP BY (x%5)
+    }
   } -test {
-    faultsim_test_result {0 {100 1000 100 1000 100 1000 100 1000 100 1000}}
+    faultsim_test_result {0 {40 1000 40 1000 40 1000 40 1000 40 1000}}
   }
 }
 
+catch { db close }
+sqlite3_shutdown
+sqlite3_config_worker_threads 0
+set t(0) singlethread
+set t(1) multithread
+set t(2) serialized
+sqlite3_config $t($sqlite_options(threadsafe))
+sqlite3_initialize
 finish_test