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* [[Data Logger]]
* [[Data Logger]]
* [[Lazylogger]]
* [[Lazylogger]]
* [[/Lazy ODB tree]]
</div>
</div>




=== Creating the /Lazy tree ===
== Creating the /Lazy tree ==
This tree is created with default parameters on the first activation of the <span style="color:darkcyan;">''lazylogger''</span>  utility . This task connects to a defined channel (e.g. Tape, Disk) when started. Multiple instances of the program can run concurrently, connecting to a different channel (see lazylogger above).
This tree is created with default parameters on the first activation of the <span style="color:darkcyan;">''lazylogger''</span>  utility . This task connects to a defined channel (e.g. Tape, Disk) when started. Multiple instances of the program can run concurrently, connecting to a different channel (see [[lazylogger]]).


The following example shows a  <span style="color:purple; font-style:italic">/Lazy</span> tree with a <channel-name> of "Disk". A sub-tree <span style="color:purple; font-style:italic">/Lazy/Disk</span> has been created, containing sub-trees "Settings" and "Statistics". A third sub-tree "List" will be created after the first successful operation of the channel. The contents of these sub-trees is discussed below (see Settings, Statistics and List subtrees.)
The following example shows a  <span style="color:purple; font-style:italic">/Lazy</span> tree with a <channel-name> of "Disk". A sub-tree <span style="color:purple; font-style:italic">/Lazy/Disk</span> has been created, containing sub-trees "Settings" and "Statistics". A third sub-tree "List" will be created after the first successful operation of the channel. The contents of these sub-trees is discussed below (see  
[[#Explanation of the Keys in the ODB /Lazy/<channel_name>/Settings subtree|Settings]]
[[#The ODB /Lazy/<channel_name>/Statistics subtree|Statistics]] and
[[#The ODB /Lazy/<channel_name>/List subtree|List]] subtrees.)


  [local:pol:S]/>ls /lazy/disk
  [local:pol:S]/>ls /lazy/disk
Line 16: Line 18:
  List
  List


=== Example of the ODB /Lazy/<channel_name>/Settings subtree ===
== The ODB /Lazy/<channel_name>/Settings subtree ==
=== Example ===
The following example shows a typical <span style="color:purple; font-style:italic">/Lazy</span>  ODB tree obtained using the [[odbedit]] "ls" command. See keys in the ODB /Lazy tree for more information on each key.  
The following example shows a typical <span style="color:purple; font-style:italic">/Lazy</span>  ODB tree obtained using the [[odbedit]] "ls" command. See keys in the ODB /Lazy tree for more information on each key.  


   Settings                     DIR
   Settings                             DIR
         Maintain free space(%)   INT    1    4    3m  0  RWD  0
         Maintain free space(%)         INT    1    4    3m  0  RWD  0
         Stay behind               INT    1    4    3m  0  RWD  -3
         Stay behind                     INT    1    4    3m  0  RWD  -3
         Alarm Class               STRING  1    32    3m  0  RWD   
         Alarm Class                     STRING  1    32    3m  0  RWD   
         Running condition         STRING  1    128  3m  0  RWD  ALWAYS
         Running condition               STRING  1    128  3m  0  RWD  ALWAYS
         Data dir                 STRING  1    256  3m  0  RWD  /home/midas/online
         Data dir                       STRING  1    256  3m  0  RWD  /home/midas/online
         Data format               STRING  1    8    3m  0  RWD  MIDAS
         Data format                     STRING  1    8    3m  0  RWD  MIDAS
         Filename format           STRING  1    128  3m  0  RWD  run%05d.mid
         Filename format                 STRING  1    128  3m  0  RWD  run%05d.mid
         Backup type               STRING  1    8    3m  0  RWD  Tape
         Backup type                     STRING  1    8    3m  0  RWD  Tape
         Execute after rewind     STRING  1    64    3m  0  RWD   
         Execute after rewind           STRING  1    64    3m  0  RWD   
         Path                     STRING  1    128  3m  0  RWD   
         Path                           STRING  1    128  3m  0  RWD   
         Capacity (Bytes)         FLOAT  1    4    3m  0  RWD  5e+09
         Capacity (Bytes)               FLOAT  1    4    3m  0  RWD  5e+09
         List label               STRING  1    128  3m  0  RWD   
         List label                     STRING  1    128  3m  0  RWD   
  Execute before writing file    STRING  1    64    11h  0  RWD  lazy_prewrite.csh
        Execute before writing file    STRING  1    64    11h  0  RWD  lazy_prewrite.csh
  Execute after writing file      STRING  1    64    11h  0  RWD  rundb_addrun.pl
        Execute after writing file      STRING  1    64    11h  0  RWD  rundb_addrun.pl
  Modulo.Position                STRING  1    8    11h  0  RWD  2.1
        Modulo.Position                STRING  1    8    11h  0  RWD  2.1
  Tape Data Append                BOOL    1    4    11h  0  RWD  y
        Tape Data Append                BOOL    1    4    11h  0  RWD  y




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An example of the subtree is shown above.
An example of the subtree is shown above.


==  <span  style="color: purple;">''Maintain free space(%)''</span>  ==
====  <span  style="color: purple;">''Maintain free space(%)''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' INT
* '''Type:''' INT
Line 54: Line 57:


* The conditions that must ALL be satisfied before removing a data file are defined as:
* The conditions that must ALL be satisfied before removing a data file are defined as:
#The data file corresponding to the given run number following the format declared under Settings/Filename format IS PRESENT on the Settings/Data Dir path.
#The data file corresponding to the given run number following the format declared under [[#Filename format#Filename format]] IS PRESENT on the Settings/Data Dir path.
#The given run number MUST appear anywhere under the <span style="color:purple; font-style:italic">Settings/List/</span> directory of ALL the Lazy channels having the same Settings/Filename format as this channel.
#The given run number MUST appear anywhere under the [[#The ODB /Lazy/<channel_name>/List subtree|List]] directory of ALL the Lazy channels having the same  
#The given run number MUST appear anywhere under the <span style="color:purple; font-style:italic">Settings/List/</span> directory of that channel
[[#Filename format#Filename format]] as this channel.
#The given run number MUST appear anywhere under the [[#The ODB /Lazy/<channel_name>/List subtree|List]] directory of that channel




==  <span  style="color: purple;">''Stay behind''</span>  ==
====  <span  style="color: purple;">''Stay behind''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' INT
* '''Type:''' INT
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==  <span  style="color: purple;">''Alarm Class''</span>  ==
====  <span  style="color: purple;">''Alarm Class''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
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==  <span  style="color: purple;">''Running Condition''</span>  ==
====  <span  style="color: purple;">''Running Condition''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
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==  <span  style="color: purple;">''Data Dir''</span>  ==
====  <span  style="color: purple;">''Data Dir''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
Line 125: Line 129:




==  <span  style="color: purple;">''Data format''</span>  ==
====  <span  style="color: purple;">''Data format''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
Line 136: Line 140:




==  <span  style="color: purple;">''Filename format''</span>  ==
====  <span  style="color: purple;">''Filename format''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
Line 149: Line 153:




==  <span  style="color: purple;">''Backup Type''</span>  ==
====  <span  style="color: purple;">''Backup type''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
Line 160: Line 164:




== <span  style="color: purple;">''Execute after rewind''</span>  ==
==== <span  style="color: purple;">''Execute after rewind''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
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This parameter  in the ODB <span style="color:purple; font-style:italic">/Lazy/<channel_name>/Settings</span> subtree  specifies
This parameter  in the ODB <span style="color:purple; font-style:italic">/Lazy/<channel_name>/Settings</span> subtree  specifies
an optional script to run after completion of a lazylogger backup set (see below [[#Capacity (Bytes)]]).
an optional script to run after completion of a lazylogger backup set (see below [[#Capacity (Bytes)|Capacity]]).




==  <span  style="color: purple;">''Path''</span>  ==
====  <span  style="color: purple;">''Path''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
Line 189: Line 193:




==  <span  style="color: purple;">''Capacity (Bytes)''</span>  ==
====  <span  style="color: purple;">''Capacity (Bytes)''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' FLOAT
* '''Type:''' FLOAT
Line 199: Line 203:
the maximum [[#Backup type|backup device]]  capacity in bytes. When this capacity is reached,the lazylogger will close the backup device and clear the [[#List label|List label]] field to prevent further backup. It will also rewind the stream device if possible.
the maximum [[#Backup type|backup device]]  capacity in bytes. When this capacity is reached,the lazylogger will close the backup device and clear the [[#List label|List label]] field to prevent further backup. It will also rewind the stream device if possible.


==  <span  style="color: purple;">''List label''</span>  ==
====  <span  style="color: purple;">''List label''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
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This parameter  in the ODB <span style="color:purple; font-style:italic">/Lazy/<channel_name>/Settings</span> subtree  specifies
This parameter  in the ODB <span style="color:purple; font-style:italic">/Lazy/<channel_name>/Settings</span> subtree  specifies
a label for a set of backed up files to the [[#Backup type|backup device]]. This label is used internally by the lazylogger for creating a new array composed of the backed up runs under the [[/Settings/List]] subdirectory, until the [[#Capacity (Bytes)|Capacity value]] has been reached. Once the backup set is complete, lazylogger will clear the "List label" field and therefore prevent any further backup until a non-empty "List label" is re-entered. However, the list label will remain under the [[/Settings/List]] key to display all run being backed up until the corresponding files have been removed from the disk.
a label for a set of backed up files to the [[#Backup type|backup device]]. This label is used internally by the lazylogger for creating a new array composed of the backed up runs under the [[#The ODB /Lazy/<channel_name>/List subtree|List]] subdirectory, until the [[#Capacity (Bytes)|Capacity]] value has been reached. Once the backup set is complete, lazylogger will clear the "List label" field and therefore prevent any further backup until a non-empty "List label" is re-entered. However, the list label will remain under the  
[[#The ODB /Lazy/<channel_name>/List subtree|List]]key to display all run being backed up until the corresponding files have been removed from the disk.


==  <span  style="color: purple;">''Execute before writing file''</span>  ==
====  <span  style="color: purple;">''Execute before writing file''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
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the lazy job. The arguments passed to the script are: input file name , output file name, current block number.
the lazy job. The arguments passed to the script are: input file name , output file name, current block number.


==  <span  style="color: purple;">''Execute after writing file''</span>  ==
====  <span  style="color: purple;">''Execute after writing file''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
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==  <span  style="color: purple;">''Modulo.Position''</span>  ==
====  <span  style="color: purple;">''Modulo.Position''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' STRING
* '''Type:''' STRING
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==  <span  style="color: purple;">''Tape Data Append''</span>  ==
====  <span  style="color: purple;">''Tape Data Append''</span>  ====
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
<div style="column-count:3;-moz-column-count:3;-webkit-column-count:3">
* '''Type:''' BOOL
* '''Type:''' BOOL
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If this key in the ODB <span style="color:purple; font-style:italic">/Lazy/<channel_name>/Settings</span> subtree  
If this key in the ODB <span style="color:purple; font-style:italic">/Lazy/<channel_name>/Settings</span> subtree  
is set to "y", the spooling of the Tape device to the End_of_Device (EOD) before starting the lazy job is enabled. This command is valid only for [[Backup Type|Backup Type]] Tape. If this flag is not enabled the lazy job starts at the current tape position.
is set to "y", the spooling of the Tape device to the End_of_Device (EOD) before starting the lazy job is enabled. This command is valid only for [[#Backup type|Backup type]] Tape. If this flag is not enabled the lazy job starts at the current tape position.




== The ODB /Lazy/<channel_name>/Statistics subtree ==


The ODB /Lazy/<channel_name>/Statistics subtree
The Statistics subtree contains general information about the status of the current lazylogger channel.
 
The Statistics ODB subtree contains general information about the status of the current lazylogger channel.


An example of the Statistics subtree for a lazylogger channel is shown below:
An example of the Statistics subtree for a lazylogger channel is shown below:


[local:pol:S]/>ls /lazy/disk/Statistics/
=== Example ===
Backup file                    000321.mid
[local:pol:S]/>ls /lazy/disk/Statistics/
File size (Bytes)              0
Backup file                    000321.mid
KBytes copied                  0
File size (Bytes)              0
Total Bytes copied              0
KBytes copied                  0
Copy progress (%)              0
Total Bytes copied              0
Copy Rate (Bytes per s)        0
Copy progress (%)              0
Backup status (%)              0
Copy Rate (Bytes per s)        0
Number of Files                173
Backup status (%)              0
Current Lazy run                321
Number of Files                173
Current Lazy run                321


== The ODB /Lazy/<channel_name>/List subtree ==


The ODB /Lazy/<channel_name>/List subtree


The List ODB subtree will contain arrays of run number associated with the array name backup-set label (see list label) . Any run number appearing in any of the arrays is considered to have been backed up.
The List subtree will contain arrays of run number associated with the array name backup-set label (see [[#List label|List label]]) . Any run number appearing in any of the arrays is considered to have been backed up.


=== Example ===
An example of the List subtree for a lazylogger channel is shown below. In this case, the list label was set to "archive".
An example of the List subtree for a lazylogger channel is shown below. In this case, the list label was set to "archive".


[local:pol:S]/>ls /lazy/disk/List
[local:pol:S]/>ls /lazy/disk/List
archive
archive
                                 230
                                 230
                                 231
                                 231
Line 295: Line 301:
                                 237
                                 237


 
[[Category:ODB Tree]]
Setting up the Lazylogger
 
The Lazylogger requires to be setup before data file can be moved. This setup consists of 4 steps:
 
Invoke the lazylogger once for setting up the appropriate ODB tree and exit. In this example, the channel is "Tape".
  >lazylogger -c Tape
Edit the newly created ODB tree. Set the Settings field(s) to match your requirements.
> odbedit -e midas
[local:midas:Stopped]/>cd /Lazy/tape/
[local:midas:Stopped]tape>ls
[local:midas:Stopped]tape>ls -lr
Key name                        Type    #Val  Size  Last Opn Mode Value
---------------------------------------------------------------------------
tape                            DIR
    Settings                    DIR
        Maintain free space(%)  INT    1    4    3m  0  RWD  0
        Stay behind            INT    1    4    3m  0  RWD  -3
        Alarm Class            STRING  1    32    3m  0  RWD 
        Running condition      STRING  1    128  3m  0  RWD  ALWAYS
        Data dir                STRING  1    256  3m  0  RWD  /home/midas/online
        Data format            STRING  1    8    3m  0  RWD  MIDAS
        Filename format        STRING  1    128  3m  0  RWD  run%05d.mid
        Backup type            STRING  1    8    3m  0  RWD  Tape
        Execute after rewind    STRING  1    64    3m  0  RWD 
        Path                    STRING  1    128  3m  0  RWD 
        Capacity (Bytes)        FLOAT  1    4    3m  0  RWD  5e+09
        List label              STRING  1    128  3m  0  RWD 
    Statistics                  DIR
        Backup file            STRING  1    128  3m  0  RWD  none
        File size [Bytes]      DOUBLE  1    4    3m  0  RWD  0
        KBytes copied          DOUBLE  1    4    3m  0  RWD  0
        Total Bytes copied      DOUBLE  1    4    3m  0  RWD  0
        Copy progress [%]      DOUBLE  1    4    3m  0  RWD  0
        Copy Rate [bytes per s] DOUBLE  1    4    3m  0  RWD  0
        Backup status [%]      DOUBLE  1    4    3m  0  RWD  0
        Number of Files        INT    1    4    3m  0  RWD  0
        Current Lazy run        INT    1    4    3m  0  RWD  0
[local:midas:Stopped]tape>cd Settings/
[local:midas:Stopped]Settings>set "Data dir" /data
[local:midas:Stopped]Settings>set "Capacity (Bytes)" 15e9
Start lazylogger in the background
>lazylogger -c Tape -D
At this point, the lazylogger is running and waiting for the list label key to be defined before starting the copy procedure. The mstat utility will display information regarding the status of the lazylogger.
 
> odbedit -e midas
[local:midas:Stopped]/>cd /Lazy/tape/Settings
[local:midas:Stopped]Settings>set "List label" cni-043
 
 
Operation of the Lazylogger
 
For every major operation of the lazylogger a message is sent to the Message buffer and will be appended to the default MIDAS log file (midas.log). These messages are the only mean of finding out What/When/Where/How the lazylogger has operated on a data file. A fragment of the midas.log for the chaos experiment is shown below. In this case, the Maintain free space(%) field was enabled which produces the cleanup of the data files and the entry in the List tree after copy.
 
Fri Mar 24 14:40:08 2000 [Lazy_Tape] 8351 (rm:16050ms) /scr0/spring2000/run08351.ybs file REMOVED
Fri Mar 24 14:40:08 2000 [Lazy_Tape] Tape run#8351 entry REMOVED
Fri Mar 24 14:59:55 2000 [Logger] stopping run after having received 1200000 events
Fri Mar 24 14:59:56 2000 [CHAOS] Run 8366 stopped
Fri Mar 24 14:59:56 2000 [Logger] Run #8366 stopped
Fri Mar 24 14:59:57 2000 [SUSI] saving info in run log
Fri Mar 24 15:00:07 2000 [Logger] starting new run
 
Fri Mar 24 15:00:07 2000 [CHAOS] Run 8367 started
Fri Mar 24 15:00:07 2000 [Logger] Run #8367 started
Fri Mar 24 15:06:59 2000 [Lazy_Tape] cni-043[15] (cp:410.6s) /dev/nst0/run08365.ybs 864.020MB file NEW
Fri Mar 24 15:07:35 2000 [Lazy_Tape] 8352 (rm:25854ms) /scr0/spring2000/run08352.ybs file REMOVED
Fri Mar 24 15:07:35 2000 [Lazy_Tape] Tape run#8352 entry REMOVED
Fri Mar 24 15:27:09 2000 [Lazy_Tape] 8353 (rm:23693ms) /scr0/spring2000/run08353.ybs file REMOVED
Fri Mar 24 15:27:09 2000 [Lazy_Tape] Tape run#8353 entry REMOVED
Fri Mar 24 15:33:22 2000 [Logger] stopping run after having received 1200000 events
Fri Mar 24 15:33:22 2000 [CHAOS] Run 8367 stopped
Fri Mar 24 15:33:23 2000 [Logger] Run #8367 stopped
Fri Mar 24 15:33:24 2000 [SUSI] saving info in run log
Fri Mar 24 15:33:33 2000 [Logger] starting new run
Fri Mar 24 15:33:34 2000 [CHAOS] Run 8368 started
Fri Mar 24 15:33:34 2000 [Logger] Run #8368 started
Fri Mar 24 15:40:18 2000 [Lazy_Tape] cni-043[16] (cp:395.4s) /dev/nst0/run08366.ybs 857.677MB file NEW
Fri Mar 24 15:50:15 2000 [Lazy_Tape] 8354 (rm:28867ms) /scr0/spring2000/run08354.ybs file REMOVED
Fri Mar 24 15:50:15 2000 [Lazy_Tape] Tape run#8354 entry REMOVED
...
Once the lazylogger has started a job on a data file, trying to terminate the application will result in producing a log message informing the user of the actual percentage of the backup completed so far. This message will repeat itself until completion of the backup, and only then the lazylogger application will terminate.
If an interruption of the lazylogger is forced (kill...), the state of the backup device is undetermined. Recovery is not possible, and the full backup set has to be redone. In order to do this, you need:
To rewind the backup device.
Delete the /Lazy/<channel_name>/List/<list label> array.
Restart the lazylogger with the -z switch which will "zap" the statistics entries.
In order to facilitate the recovery procedure, lazylogger produces an ODB ASCII file of the lazy channel tree after completion of successful operation. This file (Tape_recover.odb) stored in Data dir can be used for ODB as well as lazylogger recovery.

Revision as of 15:20, 5 June 2014


Creating the /Lazy tree

This tree is created with default parameters on the first activation of the lazylogger utility . This task connects to a defined channel (e.g. Tape, Disk) when started. Multiple instances of the program can run concurrently, connecting to a different channel (see lazylogger).

The following example shows a /Lazy tree with a <channel-name> of "Disk". A sub-tree /Lazy/Disk has been created, containing sub-trees "Settings" and "Statistics". A third sub-tree "List" will be created after the first successful operation of the channel. The contents of these sub-trees is discussed below (see Settings Statistics and List subtrees.)

[local:pol:S]/>ls /lazy/disk
Settings
Statistics
List

The ODB /Lazy/<channel_name>/Settings subtree

Example

The following example shows a typical /Lazy ODB tree obtained using the odbedit "ls" command. See keys in the ODB /Lazy tree for more information on each key.

  Settings                             DIR
       Maintain free space(%)          INT     1     4     3m   0   RWD  0
       Stay behind                     INT     1     4     3m   0   RWD  -3
       Alarm Class                     STRING  1     32    3m   0   RWD  
       Running condition               STRING  1     128   3m   0   RWD  ALWAYS
       Data dir                        STRING  1     256   3m   0   RWD  /home/midas/online
       Data format                     STRING  1     8     3m   0   RWD  MIDAS
       Filename format                 STRING  1     128   3m   0   RWD  run%05d.mid
       Backup type                     STRING  1     8     3m   0   RWD  Tape
       Execute after rewind            STRING  1     64    3m   0   RWD  
       Path                            STRING  1     128   3m   0   RWD  
       Capacity (Bytes)                FLOAT   1     4     3m   0   RWD  5e+09
       List label                      STRING  1     128   3m   0   RWD  
       Execute before writing file     STRING  1     64    11h  0   RWD  lazy_prewrite.csh
       Execute after writing file      STRING  1     64    11h  0   RWD  rundb_addrun.pl
       Modulo.Position                 STRING  1     8     11h  0   RWD  2.1
       Tape Data Append                BOOL    1     4     11h  0   RWD  y


Explanation of the Keys in the ODB /Lazy/<channel_name>/Settings subtree

An example of the subtree is shown above.

Maintain free space(%)

  • Type: INT
  • Default: 0


As the data Logger (mlogger) runs independently from the Lazylogger, the data logging device (e.g. disk) contains all the recorded data files. Under this condition, Lazylogger can be instructed to "purge" the disk after successful backup of the data onto a "slow device" (e.g. tape).

This parameter Maintain free space(%) in the ODB /Lazy/<channel_name>/Settings subtree controls the percentage of disk space required to be maintained as free (for "none" set to 0).

  • The conditions that must ALL be satisfied before removing a data file are defined as:
  1. The data file corresponding to the given run number following the format declared under #Filename format#Filename format IS PRESENT on the Settings/Data Dir path.
  2. The given run number MUST appear anywhere under the List directory of ALL the Lazy channels having the same

#Filename format#Filename format as this channel.

  1. The given run number MUST appear anywhere under the List directory of that channel


Stay behind

  • Type: INT
  • Default: 0


This parameter in the ODB /Lazy/<channel_name>/Settings subtree defines how many consecutive data files should be kept between the current run and the last lazylogger run.

Example with "Stay behind = -3"
Current acquisition run number 253 -> run00253.mid is being logged by mlogger.
Files available on the disk corresponding to runs #248, #249, #250, #251, #252.
Lazylogger will start backing up run #250 as soon as the new run 254 starts.
"Stay behind = -3" corresponds to 3 files untouched on the disk (#251, #252, #253).
If the sign (+/-) of the "Stay behind" parameter is
negative: the lazylogger will always scan the entire disk at the "Data Dir" path, from the oldest to the most recent file present for backup.
positive: lazylogger will backup starting from -x behind the current acquisition run number. Run order will be ignored.


Alarm Class

  • Type: STRING
  • Default: ""


This parameter in the ODB /Lazy/<channel_name>/Settings subtree defines specify the Alarm class to be used in case of an alarm being triggered.


Running Condition

  • Type: STRING
  • Default: "ALWAYS"


This parameter in the ODB /Lazy/<channel_name>/Settings subtree specifies the type of condition for which the lazylogger should be actived. By default the lazylogger is ALWAYS running.

The choices are
ALWAYS, NEVER, WHILE_NO_ACQ_RUNNING,
or a condition based on a single field of the ODB key<=>value

Example : In the case of high data rate acquisition it could be necessary to activate the lazylogger only

  • when the run is either paused or stopped (i.e. WHILE_NO_ACQ_RUNNING)
     odbedit > set "Running condition" WHILE_ACQ_NOT_RUNNING
  • or when some external condition is satisfied such as "low beam intensity".
     odbedit> set "Running condition" "/alias/max_rate < 200"


Data Dir

  • Type: STRING
  • Default: ""


This parameter in the ODB /Lazy/<channel_name>/Settings subtree specifies the data directory path of the data logging device (e.g. disk). If this key is present, the contents is taken as the path, otherwise the current directory is used (i.e. the path where the lazylogger client was started).


Data format

  • Type: STRING
  • Default: "MIDAS"


This parameter in the ODB /Lazy/<channel_name>/Settings subtree specifies the data format of the data files. See Format.


Filename format

  • Type: STRING
  • Default: "run%05d.mid"


This parameter in the ODB /Lazy/<channel_name>/Settings subtree specifies the filename format of the data files on the data logging device (i.e. disk). This should be the same filename format as used by the data logger to save the files (see Filename).


Backup type

  • Type: STRING
  • Default: "Tape"


This parameter in the ODB /Lazy/<channel_name>/Settings subtree specifies the type of the "backup device" to be used for the lazylog backup. It can be "Disk","Tape" or "Ftp".


Execute after rewind

  • Type: STRING
  • Default: ""


This parameter in the ODB /Lazy/<channel_name>/Settings subtree specifies an optional script to run after completion of a lazylogger backup set (see below Capacity).


Path

  • Type: STRING
  • Default: ""


This parameter in the ODB /Lazy/<channel_name>/Settings subtree specifies the backup device path.

There are three possible types of Path:

  • For Tape : e.g. /dev/nst0- (UNIX like).
  • For Disk : e.g. /data1/myexpt
  • For Ftp : host,port,user,password,directory


Capacity (Bytes)

  • Type: FLOAT
  • Default: 5e9


This parameter in the ODB /Lazy/<channel_name>/Settings subtree specifies the maximum backup device capacity in bytes. When this capacity is reached,the lazylogger will close the backup device and clear the List label field to prevent further backup. It will also rewind the stream device if possible.

List label

  • Type: STRING
  • Default: ""


This parameter in the ODB /Lazy/<channel_name>/Settings subtree specifies a label for a set of backed up files to the backup device. This label is used internally by the lazylogger for creating a new array composed of the backed up runs under the List subdirectory, until the Capacity value has been reached. Once the backup set is complete, lazylogger will clear the "List label" field and therefore prevent any further backup until a non-empty "List label" is re-entered. However, the list label will remain under the Listkey to display all run being backed up until the corresponding files have been removed from the disk.

Execute before writing file

  • Type: STRING
  • Default: ""


This parameter in the ODB /Lazy/<channel_name>/Settings subtree permits a script to be run before the beginning of the lazy job. The arguments passed to the script are: input file name , output file name, current block number.

Execute after writing file

  • Type: STRING
  • Default: ""


This parameter in the ODB /Lazy/<channel_name>/Settings subtree permits a script to be run after the completion of the lazy job. The arguments passed to the scripts are: list label, current job number, source path, file name, file size in MB, current block number.


Modulo.Position

  • Type: STRING
  • Default: ""


This field in the ODB /Lazy/<channel_name>/Settings subtree is for multiple instances of the lazylogger where each instance works on a sub-set of run number. By specifying the Modulo.Position you're telling the current lazy instance how many instances are simultaneously running (3.) and the position of which this instance is assigned to (.1) As an example for 3 lazyloggers running simultaneously the field assignment should be :

 Channel    Field    Run#
 Lazy_1     3.0      21, 24, 27, ...
 Lazy_2     3.1      22, 25, 28, ...
 Lazy_3     3.2      23, 26, 29, ...

In the example above, the Modulo.Position is set to 2.1 , indicating this is instance 1, and two lazyloggers are running.


Tape Data Append

  • Type: BOOL
  • Default: "y"


If this key in the ODB /Lazy/<channel_name>/Settings subtree is set to "y", the spooling of the Tape device to the End_of_Device (EOD) before starting the lazy job is enabled. This command is valid only for Backup type Tape. If this flag is not enabled the lazy job starts at the current tape position.


The ODB /Lazy/<channel_name>/Statistics subtree

The Statistics subtree contains general information about the status of the current lazylogger channel.

An example of the Statistics subtree for a lazylogger channel is shown below:

Example

[local:pol:S]/>ls /lazy/disk/Statistics/
Backup file                     000321.mid
File size (Bytes)               0
KBytes copied                   0
Total Bytes copied              0
Copy progress (%)               0
Copy Rate (Bytes per s)         0
Backup status (%)               0
Number of Files                 173
Current Lazy run                321

The ODB /Lazy/<channel_name>/List subtree

The List subtree will contain arrays of run number associated with the array name backup-set label (see List label) . Any run number appearing in any of the arrays is considered to have been backed up.

Example

An example of the List subtree for a lazylogger channel is shown below. In this case, the list label was set to "archive".

[local:pol:S]/>ls /lazy/disk/List
archive
                               230
                               231
                               232
                               233
                               234
                               235
                               236
                               237