Use seperate page caches pools for each sqlite connection.

Due to multiple different subsystems using sqlite, the shared global page
cache policy does not suite our use-cases on Chrome very well.  This CL
enables a compile time flag to be set to disable shared cache pools.

BUG=243769

Review URL: https://chromiumcodereview.appspot.com/17413004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@207619 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 45 insertions, 4 deletions

diff --git a/third_party/sqlite/README.chromium b/third_party/sqlite/README.chromium
index d129d62..6becfe4 100644
--- a/third_party/sqlite/README.chromium
+++ b/third_party/sqlite/README.chromium
@@ -73,6 +73,8 @@ mac_time_machine.patch
 system-sqlite.patch
 sqlite-3.7.6.3-fix-out-of-scope-memory-reference.patch
 misalignment.patch
+memcmp.patch
+separate_cache_pool.patch
 
 So, e.g. you could do this to apply all our patches to vanilla SQLite:
 
@@ -90,6 +92,7 @@ patch -p0 < ../sqlite/system-sqlite.patch
 patch -p0 < ../sqlite/sqlite-3.7.6.3-fix-out-of-scope-memory-reference.patch
 patch -p0 < ../sqlite/misalignment.patch
 patch -p0 < ../sqlite/memcmp.patch
+patch -p0 < ../sqlite/separate_cache_pool.patch
 
 This will only be the case if all changes we make also update the corresponding
 patch files. Therefore please remember to do that whenever you make a change!
diff --git a/third_party/sqlite/amalgamation/sqlite3.c b/third_party/sqlite/amalgamation/sqlite3.c
index 9f49db1..a457c09 100644
--- a/third_party/sqlite/amalgamation/sqlite3.c
+++ b/third_party/sqlite/amalgamation/sqlite3.c
@@ -35465,10 +35465,12 @@ static sqlite3_pcache *pcache1Create(int szPage, int bPurgeable){
   int sz;               /* Bytes of memory required to allocate the new cache */
 
   /*
-  ** The seperateCache variable is true if each PCache has its own private
+  ** The separateCache variable is true if each PCache has its own private
   ** PGroup.  In other words, separateCache is true for mode (1) where no
   ** mutexing is required.
   **
+  **   *  Always use separate caches (mode-1) if SQLITE_SEPARATE_CACHE_POOLS
+  **
   **   *  Always use a unified cache (mode-2) if ENABLE_MEMORY_MANAGEMENT
   **
   **   *  Always use a unified cache in single-threaded applications
@@ -35476,7 +35478,9 @@ static sqlite3_pcache *pcache1Create(int szPage, int bPurgeable){
   **   *  Otherwise (if multi-threaded and ENABLE_MEMORY_MANAGEMENT is off)
   **      use separate caches (mode-1)
   */
-#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) || SQLITE_THREADSAFE==0
+#ifdef SQLITE_SEPARATE_CACHE_POOLS
+  const int separateCache = 1;
+#elif defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) || SQLITE_THREADSAFE==0
   const int separateCache = 0;
 #else
   int separateCache = sqlite3GlobalConfig.bCoreMutex>0;
diff --git a/third_party/sqlite/separate_cache_pool.patch b/third_party/sqlite/separate_cache_pool.patch
new file mode 100644
index 0000000..cf22f35
--- /dev/null
+++ b/third_party/sqlite/separate_cache_pool.patch
@@ -0,0 +1,29 @@
+diff --git src/pcache1.c src/pcache1.c
+index ad44395..e4d0705 100644
+--- src/pcache1.c
++++ src/pcache1.c
+@@ -549,10 +549,12 @@ static sqlite3_pcache *pcache1Create(int szPage, int bPurgeable){
+   int sz;               /* Bytes of memory required to allocate the new cache */
+ 
+   /*
+-  ** The seperateCache variable is true if each PCache has its own private
++  ** The separateCache variable is true if each PCache has its own private
+   ** PGroup.  In other words, separateCache is true for mode (1) where no
+   ** mutexing is required.
+   **
++  **   *  Always use separate caches (mode-1) if SQLITE_SEPARATE_CACHE_POOLS
++  **
+   **   *  Always use a unified cache (mode-2) if ENABLE_MEMORY_MANAGEMENT
+   **
+   **   *  Always use a unified cache in single-threaded applications
+@@ -560,7 +562,9 @@ static sqlite3_pcache *pcache1Create(int szPage, int bPurgeable){
+   **   *  Otherwise (if multi-threaded and ENABLE_MEMORY_MANAGEMENT is off)
+   **      use separate caches (mode-1)
+   */
+-#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) || SQLITE_THREADSAFE==0
++#ifdef SQLITE_SEPARATE_CACHE_POOLS
++  const int separateCache = 1;
++#elif defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) || SQLITE_THREADSAFE==0
+   const int separateCache = 0;
+ #else
+   int separateCache = sqlite3GlobalConfig.bCoreMutex>0;
diff --git a/third_party/sqlite/sqlite.gyp b/third_party/sqlite/sqlite.gyp
index ad4cc72..cb1fe6b 100644
--- a/third_party/sqlite/sqlite.gyp
+++ b/third_party/sqlite/sqlite.gyp
@@ -16,6 +16,7 @@
       'SQLITE_ENABLE_ICU',
       'SQLITE_ENABLE_MEMORY_MANAGEMENT',
       'SQLITE_SECURE_DELETE',
+      'SQLITE_SEPERATE_CACHE_POOLS',
       'THREADSAFE',
       '_HAS_EXCEPTIONS=0',
     ],
diff --git a/third_party/sqlite/src/src/pcache1.c b/third_party/sqlite/src/src/pcache1.c
index ad44395..e4d0705 100644
--- a/third_party/sqlite/src/src/pcache1.c
+++ b/third_party/sqlite/src/src/pcache1.c
@@ -549,10 +549,12 @@ static sqlite3_pcache *pcache1Create(int szPage, int bPurgeable){
   int sz;               /* Bytes of memory required to allocate the new cache */
 
   /*
-  ** The seperateCache variable is true if each PCache has its own private
+  ** The separateCache variable is true if each PCache has its own private
   ** PGroup.  In other words, separateCache is true for mode (1) where no
   ** mutexing is required.
   **
+  **   *  Always use separate caches (mode-1) if SQLITE_SEPARATE_CACHE_POOLS
+  **
   **   *  Always use a unified cache (mode-2) if ENABLE_MEMORY_MANAGEMENT
   **
   **   *  Always use a unified cache in single-threaded applications
@@ -560,7 +562,9 @@ static sqlite3_pcache *pcache1Create(int szPage, int bPurgeable){
   **   *  Otherwise (if multi-threaded and ENABLE_MEMORY_MANAGEMENT is off)
   **      use separate caches (mode-1)
   */
-#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) || SQLITE_THREADSAFE==0
+#ifdef SQLITE_SEPARATE_CACHE_POOLS
+  const int separateCache = 1;
+#elif defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) || SQLITE_THREADSAFE==0
   const int separateCache = 0;
 #else
   int separateCache = sqlite3GlobalConfig.bCoreMutex>0;