package dev;

// This file records long term issue with TDB.
public class LongTermIssues
{
    // Check about "sysctl -w /proc/sys/vm/flush_mmap_pages=0"
    // and dirty_bytes=30000000000 and dirty_background_bytes = 15000000000 
    // /proc/MemInfo
    // HugePages, DirectMap, Mapped meanings.
    // http://mail-archives.apache.org/mod_mbox/incubator-jena-users/201106.mbox/%3CBANLkTimn_iPNwELBfq7V99rC86KtgAAzaw@mail.gmail.com%3E
    // echo "0" > /proc/sys/vm/nr_hugepages

    /* [FREC]
     * Files: 
     *   BPlusTreeNode.split (needs further checking e.g. delete).
     *   BPTreeNodeMgr.formatBPTreeNode
     *   BPlusTreeParams.calcOrder
     *   BPTreeNodeBuilder.hasNext
     * When storing (key,value) pairs, for a real value (the hash->offset map for the nodetable)
     * the B+Tree node has a the full record, but the value is not used. 
     * 
     * Found during 0.8.8 development.
     * Left to maximise compatibility.
     * Fix when a format change occurs. 
     * 
     * (related: check that leaf data blocks are filled to completion). 
     */
    
    /* Use 63 bit NodeId, 1 bit for inline/external */

    /* BNodes are written without leading zeros. */

    /* Binary node table. */
    
    /* prefixes index to be called "GPU", not "prefixIdx" (for consistency) */  
    
    /* New file layout 
     *   class Block(id, ByteBuffer on disk)
     *   Central file management
     *   Central cache management
     *   File with a control block; multiple "block sequences" (= BlockMgr). 
     *   getRoot.
     *   Free chain management
     */
    
    /* See // FREE */
}