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<h1 class="topictitle1">Methods to reduce the storage that journal receivers use</h1>
<div><p>Reduce the size of journal entries by methods such as journaling
after-images only, or specifying certain journaling options including the
Fixed Length Data (FIXLENDTA) option on the <span class="cmdname">Create Journal (CRTJRN)</span> and <span class="cmdname">Change
Journal (CHGJRN)</span> commands.</p>
<p>Methods to reduce the storage needed for journaling are as follows:</p>
<dl><dt class="dlterm">Journal after-images only</dt>
<dd>Unless you are using commitment control, after-images are sufficient for
your recovery needs. When you start journaling, the default is to journal
after-images only. You can use the <span class="cmdname">Change Journal Object (CHGJRNOBJ)</span> command
to stop journaling before-images without ending journaling for that object.</dd>
<dt class="dlterm">Omit the journal entries for open, close or force operations to journaled
objects</dt>
<dd>You can omit these journal entries with the OMTJRNE parameter on the <span class="cmdname">Start
Journal Physical file (STRJRNPF)</span> or <span class="cmdname">Start Journal (STRJRN)</span> command.
For database files (tables), you can select <span class="uicontrol">Exclude open and close
entries</span> when you start journaling with iSeries™ Navigator. For integrated file
system objects, ensure that <span class="uicontrol">Include open, close, and synchronization
entries</span> is not selected when you start journaling with iSeries Navigator.
You can also use the <span class="cmdname">CHGJRNOBJ</span> command to start omitting
these journal entries for objects that you are currently journaling.<p><img src="./delta.gif" alt="Start of change" />Omitting
these journal entries can have a noticeable effect on both space and performance
if an application opens, closes, or forces objects frequently.
Also, any time one looks up an object in a directory, that can cause an open
and close entry to occur for that directory. This can be a lot of additional
journal entries if they are not omitted from the directory objects. However,
if you omit the journal entries for opening and closing objects, you cannot
perform the following tasks:<img src="./deltaend.gif" alt="End of change" /></p>
<ul><li>Use open and close boundaries when applying or removing journal changes
(the TOJOBO and TOJOBC parameters).</li>
<li>Audit which users open particular objects.</li>
</ul>
</dd>
<dt class="dlterm">Swap journal receivers, save them, and free storage more frequently</dt>
<dd>Frequently saving and freeing storage for journal receivers help reduce
the auxiliary storage that the receivers use. However, moving journal receivers
off-line increases your recovery time because receivers have to be restored
before journal changes can be applied.</dd>
<dt class="dlterm">Specify receiver size options that can decrease journal receiver size</dt>
<dd>Specifying the following receiver size options can help reduce journal
receivers size:<ul><li>Remove internal entries. This causes the system to periodically remove
internal entries that it no longer needs, such as access path entries.</li>
<li>Minimize the fixed-length portion the journal entry. This causes the system
to no longer deposit all of the data selectable by the FIXLENDTA parameter
in the journal entry, thus reducing the size of the entries. However, if you
require this journal entry information for audit or other uses, you cannot
use this storage saving technique. Additionally, it reduces the options available
as selection criteria used on the following commands and API: <ul><li><span class="cmdname">Display Journal (DSPJRN)</span> command</li>
<li><span class="cmdname">Receiver Journal Entry (RCVJRNE)</span> command</li>
<li><span class="cmdname">Retrieve Journal Entry (RTVJRNE)</span> command</li>
<li><span class="cmdname">Compare Journal Images (CMPJRNIMG)</span> command</li>
<li><span class="cmdname">Apply Journaled Changes (APYJRNCHG)</span> command</li>
<li><span class="cmdname">Apply Journaled Changes Extend (APYJRNCHGX)</span> command</li>
<li><span class="cmdname">Remove Journaled Changes (RMVJRNCHG)</span> command</li>
<li><span class="apiname">Retrieve Journaled Entries (QjoRetrieveJournalEntries)</span> API</li>
</ul>
</li>
</ul>
</dd>
<dt class="dlterm">Minimized entry-specific data for journals</dt>
<dd>Minimizing entry-specific data allows the system to write data to the
journal entries in a minimized format.</dd>
<dt class="dlterm">Select the fixed-length options for data carefully</dt>
<dd>Fixed-length options can quickly increase the size of your journal receiver.
The journal receiver calculator can help you determine the effect of fixed-length
options on your auxiliary storage.</dd>
<dt class="dlterm">If you are journaling a physical file, specify <samp class="codeph">SHARE(*YES)</samp> for
the file.</dt>
<dd>You can do this using the <span class="cmdname">Create Physical File (CRTPF)</span> command
or the <span class="cmdname">Change Physical File (CHGPF)</span> command. The system
writes a single open and close entry regardless of how often the shared open
data path (ODP) is opened or closed within a routing step.</dd>
</dl>
</div>
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<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="rzakiplnuseaux.htm" title="If you are journaling an object, journal management writes a copy of every object change to the journal receiver. It writes additional entries for object level activity, such as opening and closing the object, adding a member, or changing an object attribute. If you have a busy system and journal many objects, your journal receivers can quickly become very large.">Plan for journal use of auxiliary storage</a></div>
</div>
<div class="relconcepts"><strong>Related concepts</strong><br />
<div><a href="rzakisizeoptions.htm" title="A journal receiver holds journal entries that you might use for recovery and entries that the system might use for recovery. For example, you might use record level entries, such as database record changes, and file level entries, such as the entry for opening or closing a file. Also, the system writes entries that you never see or use, such as entries for explicitly journaled access paths, for SMAPP, or for commitment control.">Receiver size options for journals</a></div>
<div><a href="rzakiintrusion.htm" title="You can use the Fixed Length Data (FIXLENDTA) parameter of Create Journal (CRTJRN) and Change Journal (CHGJRN) commands to audit security related activity for journaled objects on your system.">Fixed-length options for journal entries</a></div>
<div><a href="rzakirauxstore.htm" title="Auxiliary storage will be required on both the source and target systems. The amount that is required will be about the same on both systems.">Remote journals and auxiliary storage</a></div>
</div>
<div class="reltasks"><strong>Related tasks</strong><br />
<div><a href="rzakiperform.htm" title="There are two main performance objectives for the remote journal function. To provide a timely delivery of journal entries to a target system and to minimize impacts to the journaling throughput on the source system.">Factors that affect remote journal performance</a></div>
</div>
<div class="relinfo"><strong>Related information</strong><br />
<div><a href="rzakisizecalc.htm">Journal receiver calculator</a></div>
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