SEQPDL parameter: Difference between revisions

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<dd>4096
<dd>4096
<dt>Parameter type
<dt>Parameter type
<dd>System
<dd>Utable
<dt>Where set
<dt>Where set
<dd>User 0 parameter line
<dd>On user's parameter line or reset by UTABLE command
<dt>Related products
<dt>Related products
<dd>All
<dd>All
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the amount of free space that must be present in the user's Push Down       
the amount of free space that must be present in the user's Push Down       
List in order for the SOUL sequencer to proceed with the next             
List in order for the SOUL sequencer to proceed with the next             
quad code.                                                              
quad code.  
The new default is 4096 bytes.  The old value was 1024 bytes.           
                                 
The maximum value is 8192 bytes.                                        
The minumum and default value of SEQPDL is 4096 bytes.   
SEQPDL is a system level                                                 
 
parameter and can only be set on User 0's parameter line.                
The maximum value is 8192 bytes.  
This parameter allows enough PDL space in order for                     
 
the lower level journaling routines to handle error conditions          
SEQPDL is a user resettable parameter and can be set on the user's parameter line or reset by the <var>[[UTABLE_command|UTABLE]]</var> command.                                                              
properly without breaking files.  
 
Formerly the amount of free space was 1024, which was hardcoded internally in the Model 204 
nucleus.  With 1024 bytes there were edge cases where abends would   
break files, resulting in ERROR 2126 USER'S PUSHDOWN LIST OVERFLOWED. SEQPDL is provided to allow enough PDL space so that   
all of the lower level journaling routines can process error          
conditions without breaking files. The default value of SEQPDL adds 3072 bytes of free space.                                   
                                                                                                              
                                                                                                              
SEQPDL might require you to increase                              
<p class="note"><b>Note:</b> If your applications' actual use of free space in the User Push Down List approaches the limit that you have set in LPDLST, to avoid a PDL overflow you might need to increase the value of LPDLST by up to 3072 bytes (or more if you set a larger value for SEQPDL). </p>
the size of the user Push Down List (UTABLE LPDLST parameter) by up to  
3072 bytes, or more if you specify a value for SEQPDL that is larger     
than the 4096 default value.  This increase should avoid any issues associated   
with ERROR 2126 USER'S PUSHDOWN LIST OVERFLOWED.  


[[Category:Parameters]]
[[Category:Parameters]]
[[Category:System parameters]]
[[Category:System parameters]]

Latest revision as of 10:10, 30 May 2017

Minimum PDL available for sequencer

Summary

Default value
4096
Parameter type
Utable
Where set
On user's parameter line or reset by UTABLE command
Related products
All
Introduced
Model 204 version 7.5

Description

The SEQPDL parameter controls the amount of free space that must be present in the user's Push Down List in order for the SOUL sequencer to proceed with the next quad code.

The minumum and default value of SEQPDL is 4096 bytes.

The maximum value is 8192 bytes.

SEQPDL is a user resettable parameter and can be set on the user's parameter line or reset by the UTABLE command.

Formerly the amount of free space was 1024, which was hardcoded internally in the Model 204 nucleus. With 1024 bytes there were edge cases where abends would break files, resulting in ERROR 2126 USER'S PUSHDOWN LIST OVERFLOWED. SEQPDL is provided to allow enough PDL space so that all of the lower level journaling routines can process error conditions without breaking files. The default value of SEQPDL adds 3072 bytes of free space.

Note: If your applications' actual use of free space in the User Push Down List approaches the limit that you have set in LPDLST, to avoid a PDL overflow you might need to increase the value of LPDLST by up to 3072 bytes (or more if you set a larger value for SEQPDL).