Bug #28751 Lots of memory locked in memory causes high kswapd

- add odirect option for lcp+backup+redo log to lower CPU/kswapd usage
- writing odirect removes need for kernel write buffers avoiding kswapd to kick in

1 files changed, 24 insertions, 5 deletions

diff --git a/storage/ndb/tools/restore/Restore.cpp b/storage/ndb/tools/restore/Restore.cpp
index 3d466384782..15e442a4f35 100644
--- a/storage/ndb/tools/restore/Restore.cpp
+++ b/storage/ndb/tools/restore/Restore.cpp
@@ -867,13 +867,32 @@ bool RestoreDataIterator::readFragmentHeader(int & ret, Uint32 *fragmentId)
   
   debug << "RestoreDataIterator::getNextFragment" << endl;
   
-  if (buffer_read(&Header, sizeof(Header), 1) != 1){
+  while (1)
+  {
+    /* read first part of header */
+    if (buffer_read(&Header, 8, 1) != 1)
+    {
+      ret = 0;
+      return false;
+    } // if
+
+    /* skip if EMPTY_ENTRY */
+    Header.SectionType  = ntohl(Header.SectionType);
+    Header.SectionLength  = ntohl(Header.SectionLength);
+    if (Header.SectionType == BackupFormat::EMPTY_ENTRY)
+    {
+      void *tmp;
+      buffer_get_ptr(&tmp, Header.SectionLength*4-8, 1);
+      continue;
+    }
+    break;
+  }
+  /* read rest of header */
+  if (buffer_read(((char*)&Header)+8, sizeof(Header)-8, 1) != 1)
+  {
     ret = 0;
     return false;
-  } // if
-  
-  Header.SectionType  = ntohl(Header.SectionType);
-  Header.SectionLength  = ntohl(Header.SectionLength);
+  }
   Header.TableId  = ntohl(Header.TableId);
   Header.FragmentNo  = ntohl(Header.FragmentNo);
   Header.ChecksumType  = ntohl(Header.ChecksumType);