D_BTreeController


1   /*
2   
3      Derby - Class org.apache.derby.impl.store.access.btree.D_BTreeController
4   
5      Licensed to the Apache Software Foundation (ASF) under one or more
6      contributor license agreements.  See the NOTICE file distributed with
7      this work for additional information regarding copyright ownership.
8      The ASF licenses this file to you under the Apache License, Version 2.0
9      (the "License"); you may not use this file except in compliance with
10     the License.  You may obtain a copy of the License at
11  
12        http://www.apache.org/licenses/LICENSE-2.0
13  
14     Unless required by applicable law or agreed to in writing, software
15     distributed under the License is distributed on an "AS IS" BASIS,
16     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17     See the License for the specific language governing permissions and
18     limitations under the License.
19  
20   */
21  
22  package org.apache.derby.impl.store.access.btree;
23  
24  import org.apache.derby.iapi.reference.Property;
25  
26  import org.apache.derby.iapi.services.context.ContextManager;
27  import org.apache.derby.iapi.services.diag.Diagnosticable;
28  import org.apache.derby.iapi.services.diag.DiagnosticableGeneric;
29  import org.apache.derby.iapi.services.diag.DiagnosticUtil;
30  import org.apache.derby.iapi.services.monitor.Monitor;
31  import org.apache.derby.iapi.services.sanity.SanityManager;
32  import org.apache.derby.iapi.db.Database;
33  import org.apache.derby.iapi.error.StandardException;
34  import org.apache.derby.iapi.store.access.AccessFactory;
35  import org.apache.derby.iapi.store.access.ConglomerateController;
36  import org.apache.derby.iapi.store.access.TransactionController;
37  import org.apache.derby.iapi.store.raw.ContainerHandle;
38  import org.apache.derby.iapi.store.raw.Page;
39  
40  import java.util.Properties  ;
41  
42  /**
43  
44    A BTreeDiag class is a "helper" class for the rest of the btree generic
45    code.  It is separated into a separate class so that it can be compiled
46    out if necessary (or loaded at runtime if necessary).
47  
48    <p>
49    more info.
50  **/
51  class LevelInfo
52  {
53      public int num_pages          = 0; // number of pages in heap.
54      public int num_overflow_pgs   = 0; // number of overflow pages heap.
55      public int num_entries        = 0; // number recs on page
56      public int num_deleted        = 0; // number of recs on page marked deleted.
57      public long max_pageno        = 0; // biggest page number allocated
58      public long num_free_bytes    = 0; // number of free bytes on the pages.
59      public long num_res_bytes     = 0; // number of reserved bytes on the pages.
60      public long num_overflow_rows = 0; // number of over flow rows on page.
61      public long num_rowsize_bytes = 0; // number of bytes in rows.
62      public long num_slottab_bytes = 0; // number of bytes in slot table.
63      public long min_rowsize_bytes = Long.MAX_VALUE; // length of shortest row.
64      public long max_rowsize_bytes = Long.MIN_VALUE; // length of longest row.
65  }
66  
67  public class D_BTreeController extends DiagnosticableGeneric
68  {
69      /* Private/Protected methods of This class: */
70      private static void diag_page(
71      OpenBTree   open_btree,
72      ControlRow  control_row, 
73      Properties    prop,
74      LevelInfo   level_info[])
75          throws StandardException
76      {
77          LevelInfo li    = level_info[control_row.getLevel()];
78          Page      page  = control_row.page;
79  
80  
81  
82          li.num_pages++;
83          li.num_entries += (page.recordCount() - 1);
84          li.num_deleted += (page.recordCount() - page.nonDeletedRecordCount());
85          li.max_pageno  = Math.max(li.max_pageno, page.getPageNumber());
86  
87          DiagnosticUtil.findDiagnostic(page).diag_detail(prop);
88  
89  
90          DiagnosticUtil.findDiagnostic(page).diag_detail(prop);
91  
92          // number of free bytes on page.
93          int free_bytes = 
94              Integer.parseInt(prop.getProperty(Page.DIAG_BYTES_FREE));
95  
96          li.num_free_bytes += free_bytes;
97  
98          // number of bytes reserved on page.
99          int res_bytes = 
100             Integer.parseInt(prop.getProperty(Page.DIAG_BYTES_RESERVED));
101 
102         li.num_res_bytes += res_bytes;
103 
104         // overflow rows.
105         int overflow = 
106             Integer.parseInt(prop.getProperty(Page.DIAG_NUMOVERFLOWED));
107 
108         li.num_overflow_rows += overflow;
109 
110         // size of rows.
111         int rowsize = 
112             Integer.parseInt(prop.getProperty(Page.DIAG_ROWSIZE));
113 
114         li.num_rowsize_bytes += rowsize;
115 
116         // size of slot table.
117         int slottable_size = 
118             Integer.parseInt(prop.getProperty(Page.DIAG_SLOTTABLE_SIZE));
119 
120         li.num_slottab_bytes += slottable_size;
121 
122         // minimum row size.
123         int min_rowsize = 
124             Integer.parseInt(prop.getProperty(Page.DIAG_MINROWSIZE));
125 
126         li.min_rowsize_bytes = Math.min(li.min_rowsize_bytes, min_rowsize);
127 
128         // maximum row size.
129         int max_rowsize = 
130             Integer.parseInt(prop.getProperty(Page.DIAG_MAXROWSIZE));
131 
132         li.max_rowsize_bytes = Math.max(li.max_rowsize_bytes, max_rowsize);
133     }
134 
135     private static void diag_level(
136     OpenBTree   open_btree,
137     ControlRow  control_row, 
138     Properties    prop,
139     LevelInfo   level_info[])
140         throws StandardException
141     {
142         ControlRow      child = null;
143 
144         diag_page(open_btree, control_row, prop, level_info);
145 
146         try
147         {
148             child = control_row.getLeftChild(open_btree);
149 
150             if (child != null)
151             {
152                 // this is a branch page.
153                 if (SanityManager.DEBUG)
154                     SanityManager.ASSERT(
155                         control_row instanceof BranchControlRow);
156 
157                 BranchControlRow branch = (BranchControlRow) control_row;
158 
159                 diag_level(open_btree, child, prop, level_info);
160                 child.release();
161                 child = null;
162 
163                 int numslots = branch.page.recordCount();
164                 for (int slot = 1; slot < numslots; slot++)
165                 {
166                     child = branch.getChildPageAtSlot(open_btree, slot);
167                     diag_level(open_btree, child, prop, level_info);
168                     child.release();
169                     child = null;
170                 }
171             }
172         }
173         finally
174         {
175             if (child != null)
176                 child.release();
177         }
178 
179         return;
180     }
181 
182     private static String   out_summary(
183     String    hdr,
184     long    value,
185     double  ratio,
186     String    ratio_desc)
187     {
188         String   double_str = "" + ratio;
189 
190         String   short_str = double_str.substring(
191             0, Math.min(double_str.lastIndexOf(".") + 3, double_str.length()));
192 
193         return(
194             "\t" + hdr + value + ".\t(" + short_str + 
195             " " + ratio_desc + ").\n");
196     }
197 
198     private static String   diag_onelevel(
199     Properties    prop,
200     LevelInfo   li)
201     {
202         String   ret_string   = new String  ();
203 
204         ret_string += 
205             "Btree conglom has:\n" + 
206             "\t" + prop.getProperty(Page.DIAG_PAGE_SIZE) + " bytes per page\n" +
207             "\t" + li.num_pages           + " total used pages (" +
208                 (Integer.parseInt(prop.getProperty(Page.DIAG_PAGE_SIZE)) * 
209                      li.num_pages) + 
210                 " bytes)\n"            +
211             "\tmaximum page number   = " + li.max_pageno + ".\n"         +
212             "\treserved space %      = " + prop.getProperty(Page.DIAG_RESERVED_SPACE) + "%.\n"         +
213             "\tminimum record size   = " + prop.getProperty(Page.DIAG_MINIMUM_REC_SIZE) + ".\n"         +
214             "\tpage overhead bytes   = " + prop.getProperty(Page.DIAG_PAGEOVERHEAD) + " bytes per page.\n"         +
215             "\tminimum record length = " + li.min_rowsize_bytes + ".\n" +
216             "\tmaximum record length = " + li.max_rowsize_bytes + ".\n" +
217             "\t# of bytes in rows    = " + li.num_rowsize_bytes + "." +
218                 "\t(" + 
219                 (li.num_entries == 0 ? 
220                      0 : (li.num_rowsize_bytes / li.num_entries)) + 
221                 " bytes/row).\n"                                  +
222             out_summary(
223                 "# of reserved bytes   = ", 
224                 li.num_res_bytes,
225                 (li.num_res_bytes / li.num_pages),
226                 "reserved bytes/page") +
227             out_summary(
228                 "# of free bytes       = ",
229                 li.num_free_bytes,
230                 (li.num_free_bytes / li.num_pages),
231                 "free bytes/page")  +
232             out_summary(
233                 "# of slot table bytes = ",
234                 li.num_slottab_bytes,
235                 (li.num_slottab_bytes / li.num_pages),
236                 "slot table bytes/page")  +
237             out_summary(
238                 "# of reserved+free+row+slot bytes = ",
239                 (li.num_rowsize_bytes +
240                  li.num_res_bytes     +
241                  li.num_free_bytes     +
242                  li.num_slottab_bytes),
243                 ((li.num_rowsize_bytes +
244                   li.num_res_bytes     +
245                   li.num_free_bytes     +
246                   li.num_slottab_bytes) / li.num_pages),
247                 "summed bytes/page")  +
248             out_summary(
249                 "# of total records    = ",
250                 li.num_entries,
251                 (((double) li.num_entries) / li.num_pages),
252                 "records/page") +
253             out_summary(
254                 "# of overflow records = ",
255                 li.num_overflow_rows,
256                 (((double) li.num_overflow_rows) / li.num_pages),
257                 "overflow records/page") +
258             out_summary(
259                 "# of deleted records  = ",
260                 li.num_deleted,
261                 (((double) li.num_deleted) / li.num_pages),
262                 "deleted records/page"); 
263 
264         return(ret_string);
265     }
266             
267 
268     private static String   diag_tabulate(
269     Properties    prop,
270     LevelInfo   level_info[])
271     {
272         String   ret_string   = new String  ();
273         LevelInfo   total   = new LevelInfo();
274 
275         // first tabulate totals for all levels
276         
277         for (int level = 0; level < level_info.length; level++) 
278         {
279             LevelInfo li = level_info[level];
280 
281             total.num_pages         += li.num_pages; 
282             total.num_overflow_pgs  += li.num_overflow_pgs; 
283             total.num_entries       += li.num_entries; 
284             total.num_deleted       += li.num_deleted; 
285             total.max_pageno        = Math.max(total.max_pageno, li.max_pageno);
286             total.num_free_bytes    += li.num_free_bytes; 
287             total.num_res_bytes     += li.num_res_bytes; 
288             total.num_overflow_rows += li.num_overflow_rows; 
289             total.num_rowsize_bytes += li.num_rowsize_bytes; 
290             total.num_slottab_bytes += li.num_slottab_bytes; 
291             total.min_rowsize_bytes = 
292                 Math.min(total.min_rowsize_bytes, li.min_rowsize_bytes);
293             total.max_rowsize_bytes = 
294                 Math.max(total.max_rowsize_bytes, li.max_rowsize_bytes);
295         }
296 
297         ret_string +=
298             "Btree conglom has:\n" + 
299             "\t" + prop.getProperty(Page.DIAG_PAGE_SIZE) + " bytes per page\n" +
300             "\t" + total.num_pages           + " total used pages (" +
301                 (Integer.parseInt(prop.getProperty(Page.DIAG_PAGE_SIZE)) * 
302                      total.num_pages) + 
303                 " bytes)\n"            +
304             "\tmaximum page number   = " + total.max_pageno + ".\n"         +
305             "\treserved space %      = " + prop.getProperty(Page.DIAG_RESERVED_SPACE) + "%.\n"         +
306             "\tminimum record size   = " + prop.getProperty(Page.DIAG_MINIMUM_REC_SIZE) + ".\n"         +
307             "\tpage overhead bytes   = " + prop.getProperty(Page.DIAG_PAGEOVERHEAD) + " bytes per page.\n";
308 
309         // Format Totals:
310         ret_string += diag_onelevel(prop, total);
311 
312         // Format Totals by level:
313 
314         // Totals by level:
315         for (int level = 0; level < level_info.length; level++) 
316         {
317             LevelInfo   li = level_info[level];
318 
319             ret_string += "level[" + level + "] stats:\n";
320 
321             ret_string += diag_onelevel(prop, li);
322         }
323 
324         return(ret_string);
325     }
326 
327     private static String   olddiag_tabulate(
328     Properties    prop,
329     LevelInfo   level_info[])
330     {
331         String   ret_string   = new String  ();
332         long   total_pages  = 0;
333         long   total_res    = 0;
334 
335         for (int level = 0; level < level_info.length; level++) 
336         {
337             total_pages += level_info[level].num_pages;
338         }
339 
340 
341         // Totals:
342         ret_string += 
343             "Btree conglom has:\n" + 
344             "\t" + prop.getProperty(Page.DIAG_PAGE_SIZE) + " bytes per page\n" +
345             "\t" + total_pages               + " total pages ("                +
346                 (Integer.parseInt(prop.getProperty(Page.DIAG_PAGE_SIZE)) * 
347                      total_pages) + " bytes)\n"                                +
348             "\t" + level_info.length         + " total levels\n"               +
349             "\t" + level_info[0].num_entries + " total user records\n";
350 
351         // Totals by level:
352         for (int level = 0; level < level_info.length; level++) 
353         {
354             LevelInfo   li = level_info[level];
355 
356             ret_string += "level[" + level + "] stats:\n";
357 
358             ret_string += 
359                 "\t# of pages           = " + li.num_pages      + ".\n" +
360                 "\t# of entries         = " + li.num_entries    + ".  " +
361                 "(" + (li.num_entries / li.num_pages) + " entries/page).\n" +
362                 "\t# of deleted entries = " + li.num_deleted    + ".  " +
363                 "(" + (li.num_deleted / li.num_pages) + " deleted/page).\n" +
364                 "\t# of free bytes      = " + li.num_res_bytes + ".  " +
365                 "(" + (li.num_res_bytes / li.num_pages) + " reserved bytes/page).\n" +
366                 "\t# of free bytes      = " + li.num_free_bytes + ".  " +
367                 "(" + (li.num_free_bytes / li.num_pages) + " free bytes/page).\n" +
368                 "\t# of slot table bytes= " + li.num_slottab_bytes + ".  " +
369                 "(" + (li.num_slottab_bytes / li.num_pages) + " slot table bytes/page).\n";
370         }
371 
372         return(ret_string);
373     }
374 
375     /*
376     ** Methods of Diagnosticable
377     */
378     public void init(Object   obj)
379     {
380         if (SanityManager.DEBUG)
381             SanityManager.ASSERT(obj instanceof BTreeController);
382 
383         super.init(obj);
384     }
385 
386     /**
387      * Default implementation of diagnostic on the object.
388      * <p>
389      * This routine returns a string with whatever diagnostic information
390      * you would like to provide about this object.
391      * <p>
392      * This routine returns a summary table of information about pages in
393      * each level of the btree.  It tells the height of the tree, the 
394      * average free and reserved bytes per level, and the page size.
395      * <p>
396      *
397      * @return A string with diagnostic information about the object.
398      *
399      * @exception StandardException  Standard cloudscape exception policy
400      **/
401     public String   diag()
402         throws StandardException
403     {
404         OpenBTree   open_btree  = (BTreeController) this.diag_object;
405         ControlRow  root        = null;
406         int         tree_height;
407         LevelInfo   level_info[] = null;
408         String        diag_info    = new String  ();
409 
410         
411         try
412         {
413             tree_height = open_btree.getHeight();
414             root = ControlRow.Get(open_btree, BTree.ROOTPAGEID);
415 
416             // Allocate a LevelInfo array with one entry per level of the tree.
417             level_info = new LevelInfo[tree_height];
418             for (int level = 0; level < level_info.length; level++) 
419                 level_info[level] = new LevelInfo();
420 
421             // ask page to provide diag info:
422             Properties   prop = new Properties  ();
423             prop.put(Page.DIAG_PAGE_SIZE,        "");
424             prop.put(Page.DIAG_BYTES_FREE,       "");
425             prop.put(Page.DIAG_BYTES_RESERVED,   "");
426             prop.put(Page.DIAG_RESERVED_SPACE,   "");
427             prop.put(Page.DIAG_MINIMUM_REC_SIZE, "");
428             prop.put(Page.DIAG_NUMOVERFLOWED,    "");
429             prop.put(Page.DIAG_ROWSIZE,          "");
430             prop.put(Page.DIAG_MINROWSIZE,       "");
431             prop.put(Page.DIAG_MAXROWSIZE,       "");
432             prop.put(Page.DIAG_PAGEOVERHEAD,     "");
433             prop.put(Page.DIAG_SLOTTABLE_SIZE,   "");
434 
435             diag_level(open_btree, root, prop, level_info);
436 
437 
438             diag_info = diag_tabulate(prop, level_info);
439         }
440         finally
441         {
442             if (root != null)
443                 root.release();
444         }
445 
446         return(diag_info);
447     }
448 }
449
A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame
Popular Tags