Mount Eliminator (CARTS-ME) is an optional CARTS component that temporarily redirects tape datasets to disk that are needed for a scheduled job. These datasets are off-loaded from disk and stacked to tape after the completion of the job. Mount Eliminator substantially reduces the number of required tape mounts at most data centers.
CARTS-TS must be installed and operational before completing any of the Mount Eliminator procedures described in this chapter.
See “ Mount Eliminator” on page 6 for an introduction to some of the functions provided by Mount Eliminator. The following figure summarizes the key steps in the sequence to select (1), redirect (2), and finally off-load (3) tape datasets. The Work In Progress (WIP) table monitors the progress of datasets as they proceed through each step.
Preparing Mount Eliminator
After you have installed Mount Eliminator, several tasks need to be completed before redirecting your tape datasets to disk. The next several sections in this chapter describe how to prepare Control files and set parameter values in Mount Eliminator’s procedures and started tasks.
Preparing Control Files Used by Mount Eliminator
Mount Eliminator uses two Control files to specify the conditions to redirect datasets to disk and then off-load and stack them to tape.
• CARTS -TS Control file
Determines which datasets are eligible to be redirected to disk by Mount Eliminator. Mount Eliminator can redirect only single-volume tape datasets to disk. You must select only single-volume datasets with the CARTS-TS Control file.
• Mount Eliminator Control file
Determines the operational aspects of redirecting datasets to disk and then
off-loading them to tape. For example, the Mount Eliminator Control file specifies the interval at which datasets are off-loaded to tape and which datasets, if any, to leave on disk.
Both Control files are specified by setting parameters within the Mount Eliminator CARTSFST
start-up procedure. Refer to “ CARTSFST” on page 89 for instructions to specify the Control
files to be used with Mount Eliminator.
Customizing the CARTS-TS Control File for Use with Mount Eliminator
Use the procedures discussed in “ Changing Stacking Conditions” on page 28 to create and
update a CARTS-TS Control file used by Mount Eliminator. The values within the CARTS-TS Control file select which datasets are candidates for redirection and the conditions to stack the datasets back to tape.
Stacking Conditions
• Most CARTS-TS parameters that set stacking conditions also apply to Mount
Eliminator.
Most of the fields on the Volser Ranges screen apply, such as Max datasets per output tape, Dual Copy, Number of concurrent jobs and Robotic Output, However, the Minimum scratch pool and Number of scratch tapes fields are ignored. The values within these fields stop CARTS-TS stacking after the requisite number of scratch tapes have been created. Mount Eliminator runs continuously.
• Values set from the fields of the Robotics screen also apply to Mount Eliminator.
• Set the conditions for the Mount Eliminator jobs from the Job Cards screen. You can
run a reports only job to test stacking by setting the Reports Only field of the Job Submission screen
• All parameters on the Selection Criteria screen (Minimum days before expiration,
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• Parameters on the Accounting codes, Job/Step Names, and Location Codes screens
are also ignored.
• The include/exclude statements on the Dataset Names screen can be used to
select datasets for redirection
Datasets for Redirection
A tape dataset must meet the following requirements to be redirected to disk by Mount Eliminator:
• dataset must be stored on a single tape volume (no multi-volume datasets)
• dataset matches the selection criteria specified in the CARTS-TS Control file used by
Mount Eliminator
• dataset DD statement specifies or defaults to DISP=(NEW,CATLG)
• dataset UNIT parameter specifies an esoteric specified for Mount Eliminator
processing
• dataset with a LABEL parameter can only include file number 1
A dataset with any other file number is excluded.
• No EXPDT=98000 is coded
• dataset has four or more entries in the Mount Eliminator Block table
• dataset is within the size limit specified in the Mount Eliminator Control file
Datasets are excluded from redirection by Mount Eliminator if the dataset’s JCL contains the following:
• A LABEL parameter that includes a file number greater than 1. For example,
LABEL=(2,SL,9000)
Customizing the Mount Eliminator Control File
Use the following procedure to customize the Mount Eliminator Control file.
1. Select option 6, CONTROL, from the CARTS Main Menu.
The CARTS Mount Eliminator menu appears after selecting option 6 from the Main Menu.
2. Select option 1, CONTROL, from the Mount Eliminator menu.
Mount Eliminator’s Control Files menu appears with the same options that are used with other CARTS Control files.
--- CARTS Mount Eliminator --- COMMAND ===> _ User ID PROD File maintenance
1 CONTROL Control file selection and maintenance
Status Displays
6 STATUS Mount Eliminator general status
7 WIP Mount Eliminator Work in Progress Table 8 BLOCKTAB Mount Eliminator Block Table
9 DIAG Mount Eliminator general diagnostics 10 TRACE Mount Eliminator trace table
--- Control Files --- COMMAND ===> _ User ID PROD Choose one of the following options:
1 SELECT Open an existing control file 2 CREATE Create a new control file 3 DELETE Delete a control file
4 MODEL Initialize a control file using an existing file 5 ADD Add an existing control file to the master list 6 DROP Remove a control file from the master list 7 MASTER Specify master list data set name
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3. Select option 1, SELECT, to open an existing Mount Eliminator Control file.
The Available Control Files menu appears with a list of Mount Eliminator Control files that you can select. The menu options are the same as the Control Files menu shown on page 18.
If you want to create a new Control file, you must allocate and catalog a dataset. Allocate the dataset with the following attributes:
DCB=(RECFM=VB,LRECL=5000,BLKSIZE=8000) SPACE=(TRK,(1,1))
Or, simply make a copy of an existing Mount Eliminator Control file and catalog the copy.
☞
A model Control file was created when Mount Eliminator was installed. The name ofthe dataset is listed on the IVP report. You can use the model Control file and avoid having to allocate and catalog a new file.
4. Place the cursor over the name or description of the Control file that you want to use and press ENTER.
You return to the Mount Eliminator Main Menu after selecting a Control file. The REDIRECT, STACKING, and EXCEPTIONS options are now displayed from the Main Menu. After these screen options are displayed, you can select them to change the values of a Mount Eliminator Control file..
--- CARTS Mount Eliminator --- FILE OPENED COMMAND ===> _ User ID PROD File maintenance
1 CONTROL Control file selection and maintenance 2 REDIRECT Redirection controls
3 STACKING Stacking controls
4 EXCEPTIONS Data sets to remain on DASD
Status Displays
6 STATUS Mount Eliminator general status
7 WIP Mount Eliminator Work in Progress Table 8 BLOCKTAB Mount Eliminator Block Table
9 DIAG Mount Eliminator general diagnostics 10 TRACE Mount Eliminator trace table
Control file: PROD.ME.CNTL1
5. Select option 2, REDIRECT, from the Mount Eliminator menu.
A menu appears with option fields to select your tape dataset source, target disk volume, and the maximum size of datasets that can be redirected.
Maximum size data set to redirect
Maximum size of datasets in megabytes that can be redirected to disk. If the average size of a dataset is larger than the maximum, the dataset remains on tape. Use this field to prevent large datasets from using a significant percentage of the available disk space. 00250 is the default.
Tape unit (redirect FROM)
Esoteric of the tape drives that redirected datasets are off-loaded and stacked.
If you want to specify more than one esoteric, Mount Eliminator checks the tape esoteric specified in the UNIT parameter of the creating JCL to determine whether a dataset should be redirected. The esoteric specified in the UNIT parameter must be one of the esoterics your installation has approved for redirection.
You can specify one Mount Eliminator tape esoteric with CARTS ISPF screens. If you want to redirect datasets from more than one esoteric, you must modify the HASPXJDI member of the CARTS JCLLIB dataset.
For information about modifying HASPXJDI, refer to “Step 7: Update
the Device Definition Table (Optional)” on page 45 of the CARTS For
CA-1/TMS Installation Guide.
DASD unit (redirect TO)
DASD esoteric that identifies the volumes that store redirected datasets. Mount Eliminator writes only to DASD volumes identified by this esoteric.
Mount Eliminator redirects datasets to specified disk esoterics. These esoterics are specified from the Mount Eliminator Control file screen or in member HASPXJDI.
You control the DASD volumes available to Mount Eliminator by controlling the disk esoterics it uses. To increase or decrease available disk space, increase or decrease the number of volumes defined to these esoterics. For instructions on creating or changing esoteric definitions, refer to the appropriate IBM manuals.
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7. Select option 3, STACKING, from the Mount Eliminator Main menu.
This menu provides option fields to specify the conditions to off-load and stack redirected datasets from disk back to tape.
Minimum time a data set must remain on DASD before stacking
Minimum time that redirected datasets must remain on disk before they can be stacked. Datasets cannot be off-loaded until they have been resident on disk for this minimum period. The default is 30 minutes expressed as 00:30.
Set a long enough period to increase the likelihood that a dataset still remains on disk if it is read by a subsequent job or job step,
Days are expressed as nn:DA, where nn is the number of days datasets must reside on disk before they can be stacked. Months are expressed as nn:MO, where nn is the number of months datasets must reside on disk before they can be stacked. Years are expressed as nn:YR, where nn is the number of years datasets must reside on disk before they can be stacked.
Minimum size data set to stack
Minimum size of redirected datasets that are off-loaded and stacked after they have are resident on disk. Redirected datasets remain on disk if they are smaller than the size specified in this field. The dataset is retained according to your disk management standards, not its tape management retention.
Whenever this many data sets have been redirected
Maximum number of redirected datasets that can be stored on disk. Mount Eliminator begins off-loading and stacking these datasets to tape after the maximum has been reached. --- CARTS Mount Eliminator --- COMMAND ===> _ User ID PROD
What to stack -- which data sets are eligible for offloading to tape Minimum time a data set must
remain on DASD before stacking ===> 01 : 14 (HH:MM or DA, MO, or YR) Minimum size data set to stack ===> 00010 (megabytes)
When to stack -- offload data sets when any of the following occur Whenever this many data
sets have been redirected ===> 001000
At this time interval ===> 01 : 30 (HH:MM or DA, MO, or YR) When DASD utilization reaches ===> 75 (percent)
At this time interval
Time interval in hours (HH), minutes (MM), days (DA), months (MO), and years (YR) between Mount Eliminator stacking jobs to off-load and stack redirected datasets to tape. The default interval is two hours expressed as 02:00.
Days are expressed as nn:DA, where nn is the number of days between stacking jobs. Months are expressed as nn:MO, where nn is the number of months between stacking jobs. Years are expressed as nn:YR, where nn is the number of years between stacking jobs.
When DASD utilization reaches
Maximum percent usage of disk space on a volume before Mount Eliminator off-loads datasets back to tape. Percent usage is calculated for all datasets on a volume; not just Mount Eliminator datasets. The default is 99%.
8. Enter your Mount Eliminator redirection and stacking values and press ENTER. 9. Select option 4, EXCEPTIONS, from the Mount Eliminator Main menu.
This menu allows you to specify the names of tape datasets that you want to redirect and keep permanently on disk. This screen displays the data set name exception table from the current control file. The entries in this table identify particular data sets that are to be kept permanently on DASD and never stacked back to tape. Whenever a data set becomes a candidate for stacking, Mount Eliminator checks it against this table. If the data set name matches any line in the table, it is not stacked.
Each line represents one data set name mask. You can code up to seven dataset name qualifiers on each line. The qualifiers are compared left to right with the qualifiers in the data set name during the match process.
Within each qualifier, trailing wildcards are assumed. For example, a qualifier coded as PA will match anything beginning with the letters PA -- 'PAYROLL', 'PAYABLE', and 'PA' would all be considered matches. You can restrict matches to just the characters coded by adding a trailing period. In the above example, if you coded PA. instead of PA then only PA would match. If you specify PA without a period, any qualifier beginning with the letters PA is considered a match.
A blank qualifier is considered a wildcard that matches any qualifier in that position. For example, if you specify the following mask with node 2 as a blank entry:
----1---2---3---4---5---- PAYROLL. PA
then the following data set names would be considered as matches:
PAYROLL.DAILY.PA45 PAYROLL.WEEKLY.PA60 PAYROLL.DUMMY.PA
10. Enter the name masks of the datasets that you want to exclude from redirection to disk by Mount Eliminator and return to the Main menu.
Changes made to the Control file become effective the next time you start Mount Eliminator.
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Preparing Mount Eliminator Procedures and Started Tasks
CARTSFST
The following procedure explains how to select the CARTS-TS and Mount Eliminator Control files used by Mount Eliminator. The values set within these Control files become effective the next time Mount Eliminator is started.
1. Edit the CARTSFST procedure in the CARTS PROCLIB dataset.
2. Specify the dataset name of the new CARTS-TS Control file with the CNTL parameter.
//* CARTS-TS STANDARD CONTROL FILE //CARTSFST PROC CNTL=’PROD.CTS360.CTSCNTL’
3. Specify the dataset name of the new Mount Eliminator Control file with the MECNTL parameter.
//* CARTS-ME CONTROL FILE // MECNTL='PROD.CTS360.MECNTL',
CARTSCHK Procedure
The Mount Eliminator Check Point procedure, CARTSCHK, is a member of the CARTS PROCLIB. CARTSCHK is a started task activated by the CARTSFST. At scheduled check point intervals, CARTSCHK becomes active and performs the following tasks
• Writes the contents of the Block Table from memory to the Block File stored on disk.
• Writes the contents of the Work in Progress (WIP) table stored in memory to the check
point dataset stored on disk.
• Sends a message to the console for the first 100 check points. After the 100th
message, a final message indicates that subsequent check point messages are suppressed.
• Becomes quiescent until the next scheduled check point
The default length of the CARTSCHK checkpoint interval is two minutes (120 seconds). If you want to change the length of the check point interval, edit CARTSCHK and set the new length of the interval in seconds with the EVERY parameter.
*//* CHECK POINT INTERVAL-EVERY N SECONDS //CARTSCHK PROC EVERY='120',
//* CARTS-ME BLOCK FILE DATASET NAME // BLKFILE='USR.CTS360.BLKFILE',
//*
WARNING
!
CARTSCHK must remain up (either active or in a wait) when Mount Eliminator is active. Should CARTSCHK ever abend or be inadvertently cancelled, it must be restarted as soon as possible by entering S CARTSCHK from the console.
CARTSDSK
CARTSDSK is a started task that is initially activated by Mount Eliminator’s CARTSFST start-up procedure. CARTSDSK checks the percent usage of available DASD volumes to redirect datasets. If the threshold specified in the Percentage of DASD Utilization field of the ME Control file screen has been exceeded, CARTSDSK initiates CARTSMOV to off-load redirected datasets to tape. The default DASD volume space threshold is 99%
After verifying the available space on DASD volumes, CARTSDSK becomes quiescent until the next scheduled interval.
CARTDSK runs at a specified time interval set by the EVERY parameter. The default interval is 180 seconds.
//* EXAMINE DASD % USAGE EVERY N SECONDS //CARTSDSK PROC EVERY='180',
Edit CARTSDSK and change the value of the EVERY parameter if you want to run CARTSDSK at a different interval.
CARTSMOV
CARTSMOV off-loads and stacks qualified redirected datasets to tape. CARTSMOV analyzes the datasets shown at the bottom half of the Work In Progress table (WIP). Qualified datasets are stacked according to values set in the CARTS-TS Control file.
CARTSMOV is initiated by any of the following conditions:
• By the CARTS SMF IEFU83 exit when the current period is equal to or greater than
the interval set with At this time interval field of the Mount Eliminator STACKING Control file screen.
• When the number of redirected datasets shown at the bottom half of the WIP table is
equal to or greater than the value set in the Whenever this many data sets have been redirected field of the Mount Eliminator STACKING Control file screen.
• By CARTSDSK, if the average percent usage of DASD space meets or exceeds the
threshold specified in the When DASD utilization reaches field of the Mount Eliminator STACKING Control file.
CARTSMOV produces the following stacking reports:
• CARTSRPT01
• CARTSRPT08
• CARTSRPT09
• CARTSRPT10
• CARTSRPT15
CARTSRPT15 lists the status of every dataset analyzed in the bottom half of the WIP table. Refer to this report to see how your off-load implementation is working.
If there are no datasets to off-load, the first step of CARTSMOV receives a condition code of 16 and all remaining steps are flushed. CARTSRPT15 is created in the first step and is always produced.
Starting Mount Eliminator
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Starting Mount Eliminator
The CARTSFST procedure initializes Mount Eliminator. CARTSFST is a started task and is normally run from a COMMNDxx member. Or, you can enter S CARTSFST from the console to manually start Mount Eliminator.
CARTSFST starts the CARTSCHK and CARTSDSK started tasks. Progress messages are written to the console during initialization. Mount Eliminator becomes fully operational when CARTSFST ends.
Monitoring the Status of Mount Eliminator
This section explains several online facilities to monitor ongoing Mount Eliminator activity. These facilities can be selected as options 6 through 10 of the Mount Eliminator menu.
Displaying the Current Status
After selecting option 6, STATUS, the screen shows the current operational status of Mount Eliminator.
The status of Mount Eliminator can be ACTIVE, QUIESCING, or STOPPED. If the status is either ACTIVE or QUIESCING, the following information is also displayed from the status screen:
It was started at
Time and Julian date when Mount Eliminator became active.