View source for LENQTBL and (deprecated) LRESTBL parameters

The <var>LRESTBL</var> parameter is an alias for <var>LENQTBL</var>.
<var>LRESTBL</var> is deprecated &mdash; use <var>LENQTBL</var> instead.
==Summary==
<dl>
<dt>Default value
<dd>6
<dt>Parameter type
<dd>System
<dt>Where set
<dd>On User 0's parameter line
<dt>Related products
<dd>All
<dt>Introduced
<dd><var class="product">Model 204 V2.2</var> or earlier
</dl>

==Description==
<p>
The number of entries in the resource enqueuing table to be allocated for each user</p>
<p>
The resource enqueuing table is used for many purposes. Opening many files concurrently and using nested <var>INCLUDE</var> commands contribute to filling up this table. </p>
<p>
The value of <var>LENQTBL</var> defaults to 6. However, if the product of <code>[[NUSERS parameter|NUSERS]]*LENQTBL</code> is less than 12, that product is forced to 12 so that the table will be allocated with a minimum of 12 user entries.</p>
<p>
The resource enqueuing table is a volatile structure: its entries can be allocated and deallocated very quickly. As a result, any prediction of its optimum size can only be roughly approximate. Typically, the following formula for sizing <var>LENQTBL</var> suffices, although there might be cases where you need a larger or a smaller <var>LENQTBL</var> value. </p>

===Algorithm for estimating the value of LENQTBL===
<p>
Set <var>LENQTBL</var> to the sum of the following items.</p>
<p class="code">LENQTBL = (<i>avg. no. of open permanent groups ([[Application Subsystem development|APSY]] or non-APSY)</i> 
          + <i>avg. no. of open files per user (including files in groups)</i> + 1) </p>
<p>
The 1 added at the end accounts for the maximum number of permanent procedures (APSY or non-APSY) that can be in EVAL  per user.</p>

===Algorithm for corresponding storage requirements===
<p>
The total amount of storage required for the resource enqueuing table is:</p>
<p class="code"><i>length of user entries</i> + <i>length of system header</i> + <i>length of file headers</i></p>
<p>
That is:</p>
<p class="code">(NUSERS * LENQTBL * 32) + 64 + ([[NFILES_parameter|NFILES]] * 124)
</p>
<p>
For example, if:</p>
<p>
NUSERS = 100</p>
<p>
LENQTBL = 12, which is always the minimum allocation</p>
<p>
NFILES = 200</p>
<p>
Then the calculation is as follows:</p>
<p class="code">(100 * 12 * 32) + 64 + (200 * 124) = 63,264 bytes
</p>

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