d_btreecontroller.java

derby database source code.good for you.

                "reserved bytes/page") +
            out_summary(
                "# of free bytes       = ",
                li.num_free_bytes,
                (li.num_free_bytes / li.num_pages),
                "free bytes/page")  +
            out_summary(
                "# of slot table bytes = ",
                li.num_slottab_bytes,
                (li.num_slottab_bytes / li.num_pages),
                "slot table bytes/page")  +
            out_summary(
                "# of reserved+free+row+slot bytes = ",
                (li.num_rowsize_bytes +
                 li.num_res_bytes     +
                 li.num_free_bytes     +
                 li.num_slottab_bytes),
                ((li.num_rowsize_bytes +
                  li.num_res_bytes     +
                  li.num_free_bytes     +
                  li.num_slottab_bytes) / li.num_pages),
                "summed bytes/page")  +
            out_summary(
                "# of total records    = ",
                li.num_entries,
                (((double) li.num_entries) / li.num_pages),
                "records/page") +
            out_summary(
                "# of overflow records = ",
                li.num_overflow_rows,
                (((double) li.num_overflow_rows) / li.num_pages),
                "overflow records/page") +
            out_summary(
                "# of deleted records  = ",
                li.num_deleted,
                (((double) li.num_deleted) / li.num_pages),
                "deleted records/page"); 

        return(ret_string);
    }
            

    private static String diag_tabulate(
    Properties  prop,
    LevelInfo   level_info[])
    {
        String ret_string   = new String();
        LevelInfo   total   = new LevelInfo();

        // first tabulate totals for all levels
        
        for (int level = 0; level < level_info.length; level++) 
        {
            LevelInfo li = level_info[level];

            total.num_pages         += li.num_pages; 
            total.num_overflow_pgs  += li.num_overflow_pgs; 
            total.num_entries       += li.num_entries; 
            total.num_deleted       += li.num_deleted; 
            total.max_pageno        = Math.max(total.max_pageno, li.max_pageno);
            total.num_free_bytes    += li.num_free_bytes; 
            total.num_res_bytes     += li.num_res_bytes; 
            total.num_overflow_rows += li.num_overflow_rows; 
            total.num_rowsize_bytes += li.num_rowsize_bytes; 
            total.num_slottab_bytes += li.num_slottab_bytes; 
            total.min_rowsize_bytes = 
                Math.min(total.min_rowsize_bytes, li.min_rowsize_bytes);
            total.max_rowsize_bytes = 
                Math.max(total.max_rowsize_bytes, li.max_rowsize_bytes);
        }

        ret_string +=
            "Btree conglom has:\n" + 
            "\t" + prop.getProperty(Page.DIAG_PAGE_SIZE) + " bytes per page\n" +
            "\t" + total.num_pages           + " total used pages (" +
                (Integer.parseInt(prop.getProperty(Page.DIAG_PAGE_SIZE)) * 
                     total.num_pages) + 
                " bytes)\n"            +
            "\tmaximum page number   = " + total.max_pageno + ".\n"         +
            "\treserved space %      = " + prop.getProperty(Page.DIAG_RESERVED_SPACE) + "%.\n"         +
            "\tminimum record size   = " + prop.getProperty(Page.DIAG_MINIMUM_REC_SIZE) + ".\n"         +
            "\tpage overhead bytes   = " + prop.getProperty(Page.DIAG_PAGEOVERHEAD) + " bytes per page.\n";

        // Format Totals:
        ret_string += diag_onelevel(prop, total);

        // Format Totals by level:

        // Totals by level:
        for (int level = 0; level < level_info.length; level++) 
        {
            LevelInfo   li = level_info[level];

            ret_string += "level[" + level + "] stats:\n";

            ret_string += diag_onelevel(prop, li);
        }

        return(ret_string);
    }

    private static String olddiag_tabulate(
    Properties  prop,
    LevelInfo   level_info[])
    {
        String ret_string   = new String();
        long   total_pages  = 0;
        long   total_res    = 0;

        for (int level = 0; level < level_info.length; level++) 
        {
            total_pages += level_info[level].num_pages;
        }


        // Totals:
        ret_string += 
            "Btree conglom has:\n" + 
            "\t" + prop.getProperty(Page.DIAG_PAGE_SIZE) + " bytes per page\n" +
            "\t" + total_pages               + " total pages ("                +
                (Integer.parseInt(prop.getProperty(Page.DIAG_PAGE_SIZE)) * 
                     total_pages) + " bytes)\n"                                +
            "\t" + level_info.length         + " total levels\n"               +
            "\t" + level_info[0].num_entries + " total user records\n";

        // Totals by level:
        for (int level = 0; level < level_info.length; level++) 
        {
            LevelInfo   li = level_info[level];

            ret_string += "level[" + level + "] stats:\n";

            ret_string += 
                "\t# of pages           = " + li.num_pages      + ".\n" +
                "\t# of entries         = " + li.num_entries    + ".  " +
                "(" + (li.num_entries / li.num_pages) + " entries/page).\n" +
                "\t# of deleted entries = " + li.num_deleted    + ".  " +
                "(" + (li.num_deleted / li.num_pages) + " deleted/page).\n" +
                "\t# of free bytes      = " + li.num_res_bytes + ".  " +
                "(" + (li.num_res_bytes / li.num_pages) + " reserved bytes/page).\n" +
                "\t# of free bytes      = " + li.num_free_bytes + ".  " +
                "(" + (li.num_free_bytes / li.num_pages) + " free bytes/page).\n" +
                "\t# of slot table bytes= " + li.num_slottab_bytes + ".  " +
                "(" + (li.num_slottab_bytes / li.num_pages) + " slot table bytes/page).\n";
        }

        return(ret_string);
    }

	/*
	** Methods of Diagnosticable
	*/
    public void init(Object obj)
    {
        if (SanityManager.DEBUG)
            SanityManager.ASSERT(obj instanceof BTreeController);

        super.init(obj);
    }

    /**
     * Default implementation of diagnostic on the object.
     * <p>
     * This routine returns a string with whatever diagnostic information
     * you would like to provide about this object.
     * <p>
     * This routine returns a summary table of information about pages in
     * each level of the btree.  It tells the height of the tree, the 
     * average free and reserved bytes per level, and the page size.
     * <p>
     *
	 * @return A string with diagnostic information about the object.
     *
     * @exception StandardException  Standard cloudscape exception policy
     **/
    public String diag()
        throws StandardException
    {
        OpenBTree   open_btree  = (BTreeController) this.diag_object;
        ControlRow  root        = null;
        int         tree_height;
        LevelInfo   level_info[] = null;
        String      diag_info    = new String();

        
        try
        {
            tree_height = open_btree.getHeight();
            root = ControlRow.Get(open_btree, BTree.ROOTPAGEID);

            // Allocate a LevelInfo array with one entry per level of the tree.
            level_info = new LevelInfo[tree_height];
            for (int level = 0; level < level_info.length; level++) 
                level_info[level] = new LevelInfo();

            // ask page to provide diag info:
            Properties prop = new Properties();
            prop.put(Page.DIAG_PAGE_SIZE,        "");
            prop.put(Page.DIAG_BYTES_FREE,       "");
            prop.put(Page.DIAG_BYTES_RESERVED,   "");
            prop.put(Page.DIAG_RESERVED_SPACE,   "");
            prop.put(Page.DIAG_MINIMUM_REC_SIZE, "");
            prop.put(Page.DIAG_NUMOVERFLOWED,    "");
            prop.put(Page.DIAG_ROWSIZE,          "");
            prop.put(Page.DIAG_MINROWSIZE,       "");
            prop.put(Page.DIAG_MAXROWSIZE,       "");
            prop.put(Page.DIAG_PAGEOVERHEAD,     "");
            prop.put(Page.DIAG_SLOTTABLE_SIZE,   "");

            diag_level(open_btree, root, prop, level_info);


            diag_info = diag_tabulate(prop, level_info);
        }
        finally
        {
            if (root != null)
                root.release();
        }

        return(diag_info);
    }
}