MONITOR DATASPACE command - Revision history

ELowell: /* Example 1 */

2016-09-23T16:42:27Z

Example 1

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	</table>		</table>
	<p>See [[DSPOPT parameter\|DSPOPT~~: Dataspace and hiperspace options~~]] for ~~an explanation of the terms DATASPACE TYPE, SLOWRD,~~ and ~~SLOWWR~~.</p>		<p>See the <var>[[DSPOPT parameter\|DSPOPT]]</var> parameter for more information on dataspace and hiperspace options.</p>

	==Usage==		==Usage==
	<p>Among things monitored are page usage high-water marks, number of calls to the dataspace data movement routines, the quantity of data moved to and from the dataspaces, and page-fault statistics for dataspace data movement.</p>		<p>Among things monitored are page usage high-water marks, number of calls to the dataspace data movement routines, the quantity of data moved to and from the dataspaces, and page-fault statistics for dataspace data movement.</p>

JAL: minor formatting

2015-07-14T21:54:51Z

minor formatting

← Older revision		Revision as of 21:54, 14 July 2015
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	<dd>Enables the system administrator to display the use of dataspaces and hiperspaces when tracking the use of the CCATEMP and CCASERV In Storage feature.		<dd>Enables the system administrator to display the use of dataspaces and hiperspaces when tracking the use of the CCATEMP and CCASERV In Storage feature.
	</dl>		</dl>

	==Syntax==		==Syntax==
	<p class="syntax"><b>M</b>ONITOR DATASPACE		<p class="syntax"><b>M</b>ONITOR DATASPACE
	</p>		</p>

	==Example 1==		==Example 1==
	The DATASPACE option of the MONITOR command displays dataspace and hiperspace information as shown in the following example. <b~~><var~~>Hiperspace~~</var>~~</b> is an area of virtual storage requested from the hardware's expanded storage. Access to hiperspace saves you from paging out to disk.		The <var>DATASPACE</var> option of the <var>MONITOR</var> command displays dataspace and hiperspace information as shown in the following example. <b>Hiperspace</b> is an area of virtual storage requested from the hardware's expanded storage. Access to hiperspace saves you from paging out to disk.
	<p class="code"><nowiki>NAME STORAGE TYPE 4K PAGES PAGE HWM EXTRA DATASPACES		<p class="code"><nowiki>NAME STORAGE TYPE 4K PAGES PAGE HWM EXTRA DATASPACES
	-------- ------------------- ---------- ---------- ----------------		-------- ------------------- ---------- ---------- ----------------
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	CCAAPSY 0 0 0 0 0 0 0		CCAAPSY 0 0 0 0 0 0 0
	</nowiki></p>		</nowiki></p>
	<p>The explanation of the headings in the previous example are:</p>		<p>
			The explanation of the headings in the previous example are:</p>
	<table>		<table>

	<tr> <th>		<tr class="head"> <th><p>Heading </p></th>
	<p>Heading </p>		<th><p>Meaning</p></th> </tr>
	</th> <th>
	<p>Meaning</p>
	</th> </tr>

	<tr> <th><var>		<tr> <th><var>
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	</td> </tr>		</td> </tr>

	<tr> <th><var>		<tr> <th><var><p>STORAGE TYPE </p></var></th>
	<p>STORAGE TYPE </p>		<td>
	</var></th> <td>
	<p>Type may be one of the following: </p>		<p>Type may be one of the following: </p>
	<p>Dataspace</p>		<p>Dataspace</p>
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	</td> </tr>		</td> </tr>

	<tr> <th><var>		<tr> <th nowrap><var><p>EXTRA DATASPACES </p></var></th>
	<p>EXTRA DATASPACES </p>		<td>
	</var></th> <td>
	<p>List of additional dataspace names allocated to accommodate the total number of pages. Each dataspace or hiperspace may not have more than 524,288 4K pages. Additional dataspace or hiperspace names are constructed as CCA00001, CCA00002</p>		<p>List of additional dataspace names allocated to accommodate the total number of pages. Each dataspace or hiperspace may not have more than 524,288 4K pages. Additional dataspace or hiperspace names are constructed as CCA00001, CCA00002</p>
	</td> </tr>		</td> </tr>

ELowell at 19:20, 14 July 2015

2015-07-14T19:20:31Z

← Older revision		Revision as of 19:20, 14 July 2015
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	==Example 1==		==Example 1==
	The DATASPACE option of the MONITOR command displays dataspace and hiperspace information as shown in the following example. <b><var>Hiperspace</var></b> is an area of virtual storage requested from the hardware's expanded storage. Access to hiperspace saves you from paging out to disk.		The DATASPACE option of the MONITOR command displays dataspace and hiperspace information as shown in the following example. <b><var>Hiperspace</var></b> is an area of virtual storage requested from the hardware's expanded storage. Access to hiperspace saves you from paging out to disk.
	<p class="code">NAME STORAGE TYPE 4K PAGES PAGE HWM EXTRA DATASPACES		<p class="code"><nowiki>NAME STORAGE TYPE 4K PAGES PAGE HWM EXTRA DATASPACES
	-------- ------------------- ---------- ---------- ----------------		-------- ------------------- ---------- ---------- ----------------
	CCASERVR 64-BIT MEMORY 1465 1440		CCASERVR 64-BIT MEMORY 1465 1440
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	CCATEMP 0 0 0 0 0 0 0		CCATEMP 0 0 0 0 0 0 0
	CCAAPSY 0 0 0 0 0 0 0		CCAAPSY 0 0 0 0 0 0 0
	</p>		</nowiki></p>
	<p>The explanation of the headings in the previous example are:</p>		<p>The explanation of the headings in the previous example are:</p>
	<table>		<table>

Alex: Automatically generated page update

2013-02-28T01:05:11Z

Automatically generated page update

New page

==Summary==
<dl>
<dt>Privileges
<dd>System administrator
<dt>Function
<dd>Enables the system administrator to display the use of dataspaces and hiperspaces when tracking the use of the CCATEMP and CCASERV In Storage feature.
</dl>
==Syntax==
MONITOR DATASPACE

==Example 1==
The DATASPACE option of the MONITOR command displays dataspace and hiperspace information as shown in the following example. <var>Hiperspace</var> is an area of virtual storage requested from the hardware's expanded storage. Access to hiperspace saves you from paging out to disk.
NAME STORAGE TYPE 4K PAGES PAGE HWM EXTRA DATASPACES
-------- ------------------- ---------- ---------- ----------------
CCASERVR 64-BIT MEMORY 1465 1440
CCATEMP 64-BIT MEMORY 15100 0
CCAAPSY 64-BIT MEMORY 1000 0
NAME READS WRITES PAGES READ PAGES WRITN SLOWRD SLOWWR PAGEF
-------- ------ ------- ----------- ------------ ------- ------- ------
CCASERVR 13 20 1261 1940 0 0 0
CCATEMP 0 0 0 0 0 0 0
CCAAPSY 0 0 0 0 0 0 0

The explanation of the headings in the previous example are:
<table>

<tr> <th>
Heading 
</th> <th>
Meaning
</th> </tr>

<tr> <th><var>
NAME 
</var></th> <td>
Dataspace or hiperspace name 
</td> </tr>

<tr> <th><var>
STORAGE TYPE 
</var></th> <td>
Type may be one of the following: 
Dataspace
Hiperspace scroll
Hiperspace cache
64-bit memory
</td> </tr>

<tr> <th><var>
4K PAGES 
</var></th> <td>
Number of 4K pages in a dataspace or a hiperspace
</td> </tr>

<tr> <th><var>
PAGE HWM 
</var></th> <td>
The highest 4K-page number used in a dataspace or a hiperspace
</td> </tr>

<tr> <th><var>
EXTRA DATASPACES 
</var></th> <td>
List of additional dataspace names allocated to accommodate the total number of pages. Each dataspace or hiperspace may not have more than 524,288 4K pages. Additional dataspace or hiperspace names are constructed as CCA00001, CCA00002
</td> </tr>

<tr> <th><var>
READS 
</var></th> <td>
Number of read operations against a dataspace or a hiperspace 
</td> </tr>

<tr> <th><var>
WRITES 
</var></th> <td>
Number of write operations against a dataspace or a hiperspace 
</td> </tr>

<tr> <th><var>
PAGES READ 
</var></th> <td>
Number of 4K pages read from a dataspace or a hiperspace 
</td> </tr>

<tr> <th><var>
PAGES WRITN 
</var></th> <td>
Number of 4K pages written to a dataspace or a hiperspace
</td> </tr>

<tr> <th><var>
SLOWRD 
</var></th> <td>
Number of 4K pages read from a dataspace or a hiperspace without the Move Page instruction.
</td> </tr>

<tr> <th><var>
SLOWWR 
</var></th> <td>
Number of 4K pages written to a dataspace or a hiperspace without the Move Page instruction. 
</td> </tr>

<tr> <th><var>
PAGEF 
</var></th> <td>
Number of page faults when reading 4K page from a cache hiperspace. The statistics indicates how many times <var class="product">Model 204</var> had to do a disk read due to a 4K page fault in a cache hiperspace
</td> </tr>

</table>
See [[DSPOPT parameter|DSPOPT: Dataspace and hiperspace options]] for an explanation of the terms DATASPACE TYPE, SLOWRD, and SLOWWR.
==Usage==
Among things monitored are page usage high-water marks, number of calls to the dataspace data movement routines, the quantity of data moved to and from the dataspaces, and page-fault statistics for dataspace data movement.
Since IBM support for access to real storage above two gigabytes is limited to 2-gigabyte chunks of storage, multiple 2-gigabyte dataspaces are chained together and logically mapped as either CCATEMP or CCASERVR. 
Under the 4K PAGES heading, each X'00080000' number of 4K blocks is a 2-gigabyte chunk. There are two logical dataspaces, CCATEMP and CCASERVR. However, since IBM requires that every dataspace be named, the additional (if required) physical, 2-gigabyte chunks have generated sequential names beginning with CCA00001.
====Considering the SLOWRD and SLOWWR statistics====
The SLOWRD and SLOWWR statistic occur when <var class="product">Model 204</var> uses the Assembly Language Move Character Long (MVCL) facility, instead of the Assembly Language Move Page (MVPG) facility to move a 4-K page to or from a CCASERVR or CCAAPSY dataspace. This happens when the page that you referenced in the dataspace is not in memory. A page fault occurs and MVPG fails with a nonzero return code. When that happens, <var class="product">Model 204</var> switches to MVCL and moves the page. MVCL waits for the page fault to resolve, whereas MVPG does not. When this switching takes place you will see SLOWRD and SLOWWR statistics increase, although usually they are not significant.
In the MONITOR DATASPACE output check whether less than 20 percent of PAGES WRITN were SLOWWRs. If the percentage gets higher, it indicates that memory for dataspaces or hiperspaces is constrained and that the pages referenced when you do a server swap or an APSY load are not in memory.
The percentage of SLOWRDs and SLOWWRs generally does not represent a problem unless the percentages compared to PAGES READ or PAGES WRITN exceed 20-30 percent. Then, the only action you can take to reduce the percentages is by adding more central or expanded storage or by reducing the size of the CCASERVR or CCAAPSY dataspaces. 
==Example 2==
====Output from the operating system====
There are five physical dataspaces in the following example. When a TSO user issues the following command, where DVUSER2 is the job name of the Online using the dataspaces, the following output is displayed:
/D J,DVUSER2
IEE115I 11.27.40 2001.155 ACTIVITY 900
JOBS M/S TS USERS SYSAS INITS ACTIVE/MAX VTAM OAS
00024 00034 00015 00026 00190 00015/00065 00024
DVUSER2 ONLINE NSW J A=00AE PER=NO SMC=000
PGN=088 DMN=020 AFF=NONE
CT=122.307S ET=590.945S
WUID=JOB07991 USERID=DVUSER2
ADDR SPACE ASTE=13950B80
DSPNAME=CCA00003 ASTE=055A5300
DSPNAME=CCATEMP ASTE=033CCC80
DSPNAME=CCA00002 ASTE=055A5400
DSPNAME=CCA00001 ASTE=09A21100
DSPNAME=CCASERVR ASTE=033CC880

[[Category: System administrator commands]]
[[Category:Commands]]