Optimisation todo for loghandler added.

Debug output information fixed.
Fixed direct page referencing in write mode.


storage/maria/ma_loghandler.c:
  TODO added.
storage/maria/ma_pagecache.c:
  Debug output information fixed.
  Fixed direct page referencing in write mode.

storage/maria/ma_loghandler.c

@@ -6066,10 +6066,10 @@ translog_size_t translog_read_record(LSN lsn,
 
 
 /*
-  Force skipping to the next buffer
+  @brief Force skipping to the next buffer
 
-  SYNOPSIS
-    translog_force_current_buffer_to_finish()
+  @todo Do not copy old page content if all page protections are switched off
+  (because we do not need calculate something or change old parts of the page)
 */
 
 static void translog_force_current_buffer_to_finish()

storage/maria/ma_pagecache.c

@@ -184,7 +184,6 @@ static const char *page_cache_page_type_str[]=
 static const char *page_cache_page_write_mode_str[]=
 {
   "DELAY",
-  "NOW",
   "DONE"
 };
 
@@ -2929,7 +2928,14 @@ uchar *pagecache_valid_read(PAGECACHE *pagecache,
 
     status= block->status;
     if (!buff)
+    {
       buff=  block->buffer;
+      /* if we lock for write we must link the block to changed blocks */
+      if ((lock == PAGECACHE_LOCK_WRITE ||
+           lock == PAGECACHE_LOCK_LEFT_WRITELOCKED) &&
+          !(block->status & PCBLOCK_CHANGED))
+          link_to_changed_list(pagecache, block);
+    }
     else
     {
       if (!(status & PCBLOCK_ERROR))