Parallel ledger loader & I/O performance improvements:

- Only duplicate records from archive to writable during online_delete.
- Log duration of nodestore reads.
- Include nodestore counters in perf_log output.
- Remove gratuitous nodestore activity counting.
- Report initial sync duration in server_info and perfLog.
- Report state_accounting in perfLog.
- Make state_accounting durations more accurate.
- Parallel ledger loader.
- Config parameter to load ledgers on start.

Builds/levelization/results/loops.txt

@@ -8,7 +8,7 @@ Loop: ripple.app ripple.net
   ripple.app > ripple.net
 
 Loop: ripple.app ripple.nodestore
-  ripple.nodestore ~= ripple.app
+  ripple.app > ripple.nodestore
 
 Loop: ripple.app ripple.overlay
   ripple.overlay ~= ripple.app
@@ -28,6 +28,9 @@ Loop: ripple.basics ripple.core
 Loop: ripple.basics ripple.json
   ripple.json ~= ripple.basics
 
+Loop: ripple.basics ripple.nodestore
+  ripple.nodestore > ripple.basics
+
 Loop: ripple.basics ripple.protocol
   ripple.protocol > ripple.basics
 

Builds/levelization/results/ordering.txt

@@ -29,7 +29,6 @@ ripple.net > ripple.beast
 ripple.net > ripple.json
 ripple.net > ripple.protocol
 ripple.net > ripple.resource
-ripple.nodestore > ripple.basics
 ripple.nodestore > ripple.beast
 ripple.nodestore > ripple.core
 ripple.nodestore > ripple.json