Application scenario: Reading test with command duration analysis

In this article we would like to show you, using a real scenario, what the read test with command duration analysis is good for and which errors can be found with it that other tests in the program and classic hard drive tests do not show.

The disk

The faulty disk is a Seagate ST5000DM000 with 5TB of storage space, installed in a USB case and was used to back up a server system. The hard drive has been used in a hybrid backup solution for several years, alternating with 4 other data carriers.

The starting point

The data carrier was connected to the server to be backed up and was no longer recognized by Windows®. Switching it on and off worked without any problems, as did the power supply. However, there was no reaction under Windows®. The plate was then connected to toolstar®testLX and various tests were carried out in sequence (lowest load to highest load) carried out. This order is extremely important in order to be able to detect a severely defective data storage medium as early as possible without placing it under high load.

Test 1: SMART analysis including extra checks

The SMART analysis including the extra checks of the attributes (new from version 5.96) is used. The SMART analysis delivers within a few seconds the most important values ​​for the hard drive, including an evaluation of the manufacturer and toolhouse. SMART analysis does not represent a read or write access to the data area of ​​the disk and is only handled by the controller and its own internal memory. This creates only a minimal load on the entire medium.

In this case, the values ​​of the SMART analysis no major abnormalities. Although the plate reports a warning about the airflow temperature, this can be understood when taking into account the age and the attribute. This message can also occur from any type of data storage medium shortly after being put into operation if it regularly gets a little hotter.

------------------------------------------------------------------------

  SMART-Status (laut Platte): okay
             Gesamtbewertung: mittel

       Lebensdauer übrig (%): No data available
       Stunden eingeschaltet: 15362
                              Bestanden: nicht über 100000
    Aus- und Einschaltzyklen: 274
                              Bestanden: nicht über 20000
       Geschriebene TB insg.: 324,6
                              Bestanden: nicht über 500
       Geschriebene TB insg.: 324,6
                              Bestanden: nicht über 454

          Letzter Selbsttest: kein Fehler oder noch kein Test durchgeführt


  Fitness-Attribute                                                             
  Name:                  ID:  akt  min Schwelle Typ roh          Bewertung
  Rohfehlerrate Lesen:   1:   114  98  6        F   68.044.936      
  Start/Stop-Zyklen:     4:   100  100 20       A   841        keine
  Reallozierte Sektoren: 5:   100  100 10       F   0          noch nicht bewertet
  Positionierfehlerrate: 7:   80   60  30       F   22.050.748.658  
  Anlaufwiederholungen: 10:   100  100 97       F   0          noch nicht bewertet
  Ein/Ausschalt-Zyklen: 12:   100  100 20       A   274        keine
  End-to-End error:     184:  100  100 99       A   0          noch nicht bewertet
  Luftstromtemperatur:  190:  58   50  45       A   42         mittel

  Performance-/Info-Attribute                                                   
                                Name: ID:  akt min Schwelle Typ roh             
                          Anlaufzeit: 3:   95  92  0        F   0               
                        Betriebszeit: 9:   83  83  0        A   15.362 Stunden  
            SATA Downshift Err.Count: 183: 100 100 0        A   0               
           Bericht.nichtbeheb.Fehler: 187: 100 100 0        A   0               
                     Befehls-Timeout: 188: 100 99  0        A   4.295.032.834   
                   Große Schreibhöhe: 189: 1   1   0        A   129             
            Erschütterungsfehlerrate: 191: 100 100 0        A   0               
            Ausschalt-Rückzug-Zyklen: 192: 100 100 0        A   13              
                     Ruhezone-Zyklen: 193: 100 100 0        A   1.334           
                          Temperatur: 194: 42  50  0        A   42 °C           
           Behob.Hardwarefehler(ECC): 195: 114 100 0        A   68.044.936      
  Auf Reallokation wartende Sektoren: 197: 100 100 0        A   0               
           N.behebb.Fehler (Offline): 198: 100 100 0        A   0               
             UltraDMA-CRC-Fehlerrate: 199: 200 200 0        A   0               
                     Kopfflugstunden: 240: 100 253 0        A   3124            
         Geschriebene Sektoren insg.: 241: 100 253 0        A   697.017.004.664 
             Gelesene Sektoren insg.: 242: 100 253 0        A   21.205.510.472  


Fehler-Logs
===========

  Insg. geloggte Fehler: 0

Test 2: Fast reading benchmark

The fast reading benchmark reads different sector blocks linearly with constant jump sizes of the sectors on the hard drive, evenly distributed, and measures the speed and the ability to read the sector correctly. During this test it was already noticed that the hard drive might be slower than usual, but no sector error was indicated and the test ended properly.

------------------------------------------------------------------------

           Plattendaten: 
               Sektoren: 1.220.942.646
            Sektorgröße: 4096 Bytes
              Kapazität: 4657 GB = 4,5 TB

       Angeschlossen an: Intel 8 Series USB xHCI Host Controller

   Zu testender Bereich: ganze Platte
    Benutzte Blockgröße: 256 Sektoren

  Geschwindigkeitswerte: 
                Maximum: 11.770 KB/s
           Durchschnitt: 11.570 KB/s
                Minimum: 11.314 KB/s

               Ergebnis: bestanden
Linear read test

Test 3: Mechanics test and access time

The mechanics and access time test does not jump linearly to different sector blocks on the disk. This checks whether all targeted sector blocks are accessible and readable. No error was found in this test and the test was completed at a sufficiently fast speed.

------------------------------------------------------------------------

          Plattendaten: 
              Sektoren: 1.220.942.646
           Sektorgröße: 4096 Bytes
             Kapazität: 4657 GB = 4,5 TB

      Angeschlossen an: Intel 8 Series USB xHCI Host Controller

  Zu testender Bereich: ganze Platte
   Benutzte Blockgröße: 256 Sektoren

              Ergebnis: bestanden


Geschwindigkeit
---------------

  Durchschnittszeit: 17 ms
news_mechanik

Test 4: Reading test with command duration analysis

The reading test itself, like the other 3 tests, did not produce any errors. Only the command duration analysis showed that from sector block 5,120 onwards the response time of the hard drive was over 500ms. A number of over 500ms in the first memory area of ​​a hard drive can very quickly lead to a timeout within the operating system and applications. Under Windows, the timeout could have been triggered by the storage driver. In other situations, backup programs could crash or stop the backup due to a storage medium that doesn't respond or, in this case, responds too slowly.

------------------------------------------------------------------------

           Plattendaten: 
               Sektoren: 1.220.942.646
            Sektorgröße: 4096 Bytes
              Kapazität: 4657 GB = 4,5 TB

       Angeschlossen an: Intel 8 Series USB xHCI Host Controller

   Zu testender Bereich: ganze Platte
    Benutzte Blockgröße: 256 Sektoren

  Geschwindigkeitswerte: 
                Maximum: 40,1 MB/s
           Durchschnitt: 32,3 MB/s
                Minimum: 5.158 KB/s

               Ergebnis: abgebrochen* davor FEHLER


Meldungen
---------

  Block ab         5.120: FEHLER: Bereits 1x über 500 ms
  Block ab     1.037.312: Test durch Benutzer abgebrochen


Befehlsdauer-Analyse
--------------------

          < 100 ms: 4.032x
      100 - 250 ms: 0x
      250 - 500 ms: 0x
          > 500 ms: 11x
                    FEHLER: mehr als 500!

      Sektor 5.120: 3176 ms
     Sektor 21.504: 6388 ms
     Sektor 54.272: 12752 ms
    Sektor 119.808: 12744 ms
    Sektor 250.624: 12748 ms
    Sektor 381.696: 12748 ms
    Sektor 512.768: 13212 ms
    Sektor 643.840: 12700 ms
    Sektor 774.912: 12804 ms
    Sektor 905.984: 12716 ms
  Sektor 1.037.056: 12784 ms
default_read_test

The command acid analysis

Command duration analysis has been part of the toolstar®testLX software for a long time and toolstar®testWIN. In the standard settings, the command duration analysis is carried out automatically during the read test. A total of 3 different limit values ​​can be defined in the test. By default, 100, 250 and 500ms are entered here. In addition to the limit values, it can also be determined which exceedance and, if so, how many exceedances of these limit values ​​lead to an error during a test. By default, only the limit of 500ms is taken into account and an error is generated the first time it is exceeded.