SNAPLIMD parameter: Difference between revisions

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m (Created page with "0 or max number of occurrences of any particular snap ==Summary== <dl> <dt>Default value <dd>3 <dt>Parameter type <dd>System <dt>Where set <dd>System manager resettable <dt>Relat...")
 
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</dl>
</dl>
==Description==
==Description==
This is a bitmask parameter that controls the behavior of the <var class="product">[[Fast/Unload User Language Interface]]</var>,
This parameter limits the number of snaps which can be issued with any given snap title.  That is, it prevents some bug from using up the snaps available as specified by the <var>SNAPLIM</var> parameter.
where the bits mean:
<dl>
<dt>X'01'
<dd>Indicates that a synchronous [[Fast/Unload]] request is not to be allowed while
an updating transaction is active.
This is to prevent a ''Fast/Unload'' request that might take a long time to
complete from being run while a user has resources enqueued for an updating
transaction.
These resources would, of course, include the blocking of checkpoints if
subtransaction checkpoints are not being used.


If the X'01' bit is set, and a thread attempts a synchronous ''Fast/Unload User Language Interface''
The <code>*SNAP</code> snap title is not subject to <var>SNAPLIMD</var>, thus:
request (either via $Funload or the [[FastUnload (Recordset function)|FastUnload method]] of the Recordset class)
<ul>
in the middle of an updating transaction, the transaction will be cancelled
<li>When the <var>*SNAP</var> command is issued, each snap thus created is considered unique, and will not be suppressed due to <var>SNAPLIMD</var>.
with a message like the following:
<li>When the <var>BUMPSNAP</var> command is issued, each snap thus created is considered unique, and will not be suppressed due to <var>SNAPLIMD</var>.
    CANCELLING REQUEST: MSIR.0561: $FUNLOAD: Synchronous request during
</ul>
                        update transaction in line 43, procedure FUNTEST,
                        file ALEXPROC
<dt>X'02'
<dd>Indicates that "basic"
<var class="product">Fast/Unload</var>
messages for all users are always audited, regardless of the presence of
a <var class="product">Fast/Unload User Language Interface</var>
"report" argument.
<dt>X'04'
<dd>Indicates that <b>all</b> <var class="product">Fast/Unload</var> messages for all users, except "Field statistics"
and <var>REPORT</var> statement lines,
are always audited, regardless of the presence of a
<var class="product">Fast/Unload User Language Interface</var>
"report" argument.
The X'02' bit need not be set if the X'04' bit is set.
<dt>X'08'
<dd>Indicates that "basic"
<var class="product">Fast/Unload</var>
messages for all users are always audited in the
<var class="product">Model 204</var> audit trail, whether or not the <code>FUNAUDIT</code> DD name is present.
If the X'04' bit is on, <b>all</b> messages are audited there as well.
In the odd case that there is no <var class="product">Model 204</var> audit trail, the X'08' bit is ignored, but auditing is
performed as if the X'02' bit were on, whether it is or not.
</dl>
 
For both of the <var>FUNPARM</var> X'02' and X'04' bits, the same bit has the same meaning (for an individual user) in the <var>[[FUNPRMU parameter|FUNPRMU]]</var> user parameter; the indicated effect takes place if either of the <var>FUNPRMU</var> or <var>FUNPARM</var> bits are on.
That is also true for the X'08' bit, although there are some additional details for the X'08' bit which generally you don't need
to concern yourself with, but are explained as part of the more detailed
[[FUNPRMU parameter#Fast/Unload report processing|"Fast/Unload report processing discussion"]].
 
The X'02', X'04', and X'08' bits of this parameter, together with the same bits of <var>FUNPRMU</var>,
control the auditing of messages when using the <var class="product">Fast/Unload User Language Interface</var>.
These parameters can be used to augment the availability of auditing information, in such a way that the user or the system manager can
ensure that information is available for a single job or all jobs, without changes to any User Language
program invoking <var>[[FastUnload (Recordset function)|FastUnload]]</var>, <var>[[FastUnloadTask (Recordset function)|FastUnloadTask]]</var>, or <var>[[$Funload]]</var>.
Without the use of these parameters,
some auditing information may be available from the <code>FUNAUDIT</code> dataset, but that information may be inadequate:
for example, messages from a <var>FastUnload</var> job will not be in <code>FUNAUDIT</code> if the
<var>Report</var> parameter is used.
 
Using the X'02', X'04', and X'08' bits of these parameters is fairly straightforward and the above description should be adequate to use them. A complete description of the processing triggered by these bits is presented in the [[FUNPRMU parameter#Fast/Unload report processing|"Fast/Unload report processing discussion"]].


Note that
<ul>
<li>When a snap is suppressed due to exceeding the <var>SNAPLIM</var> parameter, the <var>SNAPID</var> parameter is incremented.
<li>If that is not the case (that is, if the <var>SNAPLIM</var> parameter is less than the <var>SNAPID</var> parameter), if there have already been at least as many snaps <b>actually produced</b> for the given snap title as the value of the <var>SNAPLIMD</var> parameter:
<ul>
<li>The snap is suppressed and the <var>SNAPID</var> parameter is <b>not</b> incremented (otherwise, the purpose of <var>SNAPLIMD</var> would be circumvented).
</ul>
</ul>
[[Category:System parameters]]
[[Category:System parameters]]
[[Category:Parameters]]
[[Category:Parameters]]
[[Category:Fast/Unload User Language Interface]]

Revision as of 00:13, 11 September 2012

0 or max number of occurrences of any particular snap

Summary

Default value
3
Parameter type
System
Where set
System manager resettable
Related products
??
Introduced
Sirius Mods 8.1 (and by zap in 8.0)

Description

This parameter limits the number of snaps which can be issued with any given snap title. That is, it prevents some bug from using up the snaps available as specified by the SNAPLIM parameter.

The *SNAP snap title is not subject to SNAPLIMD, thus:

  • When the *SNAP command is issued, each snap thus created is considered unique, and will not be suppressed due to SNAPLIMD.
  • When the BUMPSNAP command is issued, each snap thus created is considered unique, and will not be suppressed due to SNAPLIMD.

Note that

  • When a snap is suppressed due to exceeding the SNAPLIM parameter, the SNAPID parameter is incremented.
  • If that is not the case (that is, if the SNAPLIM parameter is less than the SNAPID parameter), if there have already been at least as many snaps actually produced for the given snap title as the value of the SNAPLIMD parameter:
    • The snap is suppressed and the SNAPID parameter is not incremented (otherwise, the purpose of SNAPLIMD would be circumvented).
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