Bug 661351 - Clean up code that worked around bad values from PR_GetPhysicalMemorySize [r=mak]

toolkit/components/places/nsNavHistory.cpp

@@ -135,11 +135,8 @@ using namespace mozilla::places;
 // Out of this cache, SQLite will use at most the size of the database file.
 #define DATABASE_DEFAULT_CACHE_TO_MEMORY_PERCENTAGE 6
 
-// PR_GetPhysicalMemorySize sometimes returns garbage (bug 660036).  If the
-// return value is greater than MEMSIZE_MAX_BYTES, assume it is garbage and
-// use MEMSIZE_FALLBACK_BYTES instead.  Must stay in sync with the code in
-// nsPlacesExpiration.js.
-#define MEMSIZE_MAX_BYTES 137438953472LL // 128 G
+// If the physical memory size is not available, use MEMSIZE_FALLBACK_BYTES
+// instead.  Must stay in sync with the code in nsPlacesExpiration.js.
 #define MEMSIZE_FALLBACK_BYTES 268435456 // 256 M
 
 // Maximum size for the WAL file.  It should be small enough since in case of
@@ -733,14 +730,14 @@ nsNavHistory::InitDB()
   if (cachePercentage < 0)
     cachePercentage = 0;
 
-  static PRInt64 physMem = PR_GetPhysicalMemorySize();
-  if (physMem <= 0 || physMem > MEMSIZE_MAX_BYTES)
+  static PRUint64 physMem = PR_GetPhysicalMemorySize();
+  if (physMem == 0)
     physMem = MEMSIZE_FALLBACK_BYTES;
 
-  PRInt64 cacheSize = physMem * cachePercentage / 100;
+  PRUint64 cacheSize = physMem * cachePercentage / 100;
 
   // Compute number of cached pages, this will be our cache size.
-  PRInt64 cachePages = cacheSize / mDBPageSize;
+  PRUint64 cachePages = cacheSize / mDBPageSize;
   nsCAutoString cacheSizePragma("PRAGMA cache_size = ");
   cacheSizePragma.AppendInt(cachePages);
   rv = mDBConn->ExecuteSimpleSQL(cacheSizePragma);

toolkit/components/places/nsPlacesExpiration.js

@@ -717,17 +717,14 @@ nsPlacesExpiration.prototype = {
     catch(e) {}
 
     if (this._urisLimit < 0) {
-      // PR_GetPhysicalMemorySize sometimes returns garbage (bug 660036).
-      // If the return value is greater than MEMSIZE_MAX_BYTES, assume it is
-      // garbage and use MEMSIZE_FALLBACK_BYTES instead.  Must stay in sync
-      // with the code in nsNavHistory.cpp.
-      const MEMSIZE_MAX_BYTES = 137438953472; // 128 G
+      // If physical memory size is not available, use MEMSIZE_FALLBACK_BYTES
+      // instead.  Must stay in sync with the code in nsNavHistory.cpp.
       const MEMSIZE_FALLBACK_BYTES = 268435456; // 256 M
 
       // The preference did not exist or has a negative value, so we calculate a
       // limit based on hardware.
       let memsize = this._sys.getProperty("memsize"); // Memory size in bytes.
-      if (memsize <= 0 || memsize > MEMSIZE_MAX_BYTES)
+      if (memsize <= 0)
         memsize = MEMSIZE_FALLBACK_BYTES;
 
       let cpucount = this._sys.getProperty("cpucount"); // CPU count.