More tweaking parameters, a=chris

diff --git a/src/configs/Config.php b/src/configs/Config.php
index 943deeca1..105a926c8 100755
--- a/src/configs/Config.php
+++ b/src/configs/Config.php
@@ -757,7 +757,7 @@ nsconddefine('URL_FILTER_SIZE', MEMORY_PROFILE * 5000000);
  */
 nsconddefine('NUM_URLS_QUEUE_RAM', MEMORY_PROFILE * 80000);
 /** number of documents before next gen */
-nsconddefine('NUM_DOCS_PER_PARTITION', 6 * MEMORY_PROFILE * 10000);
+nsconddefine('NUM_DOCS_PER_PARTITION', 5 * MEMORY_PROFILE * 10000);
 /** precision to round floating points document scores */
 nsconddefine('PRECISION', 10);
 /** maximum number of links to extract from a page on an initial pass*/
diff --git a/src/library/BPlusTree.php b/src/library/BPlusTree.php
index 298803563..e468af298 100644
--- a/src/library/BPlusTree.php
+++ b/src/library/BPlusTree.php
@@ -46,7 +46,7 @@ class BPlusTree
      * The MAXIMUM number of keys stored in a tree node (will split if have
      * more)
      */
-    const MAX_KEYS = 2001;
+    const MAX_KEYS = 1001;
     /**
      *
      */
diff --git a/src/library/IndexDocumentBundle.php b/src/library/IndexDocumentBundle.php
index 288c64526..e77fa574a 100644
--- a/src/library/IndexDocumentBundle.php
+++ b/src/library/IndexDocumentBundle.php
@@ -187,6 +187,9 @@ class IndexDocumentBundle implements CrawlConstants
             $num_docs_per_partition,
             PartitionDocumentBundle::PARTITION_SIZE_THRESHOLD,
             C\NS_COMPRESSORS . "GzipCompressor");
+        if (!$read_only_archive) {
+            $this->documents->index_cache_size = 1;
+        }
         $this->doc_map_tools = new PackedTableTools([
             "PRIMARY KEY" => ["DOC_KEYS", 24], "POS" => "INT",
             "SCORE" => "FLOAT"], C\NS_COMPRESSORS . "GzipCompressor");