Parameter description for SPOOLDEF

BUFSIZE=nnnn|3992

Specifies the size (1944-3992) in bytes, of each JES2 buffer. If the value specified is not a multiple of 8, it is rounded up automatically.

Each JES2 buffer is allocated to virtual storage, such that input/output block (IOB), which is 88 bytes, and the data area (the number of bytes in BUFSIZE) are always contained in a single 4K-page. The maximum value, 3992, allows 10 buffers per track for a 3380 and 12 buffers per track for a 3390.

Performance Considerations: Specifying too small a value for BUFSIZE= increases the need for spool I/O activity, thereby degrading performance. A BUFSIZE= specification of 3992 maximizes both central and virtual storage utilization for most JES2 members. This value also provides good DASD utilization. See z/OS JES2 Initialization and Tuning Guide for DASD utilization values based on BUFSIZE= values.

The BUFSIZE= parameter specification affects the size of the track group map (TGM) and the number of peripheral data definition blocks (PDDBs) which can fit into each input/output table (IOT). Therefore, BUFSIZE= must be set in order to attain a balance between better DASD or processor utilization and central storage considerations.

Modification: Cold start.

DSNAME=jxx...x|SYS1.HASPACE

Specifies a 1- to 44-character name (hyphens (-) may be included for any character except the first) which is to be used as the data set name of the JES2 spool data set. This data set is normally named SYS1.HASPACE, but its name can be changed. For example, it could be named TESTING.HASPACE by specifying the following initialization statement:

SPOOLDEF  DSNAME=TESTING.HASPACE  /* ALTERNATE TEST SPOOL DATA SET */

Modification: Cold start.

DSNMASK=jxx...x|SYS1.HASPACE

Displays the 1-44 character data set mask name, including generic characters. If the DSNAME parameter is specified with the SPOOL initialization statement or the $S SPOOL command, the DSNAME value must match either the $D SPOOLDEF DSNAME value or the $D SPOOLDEF DSNMASK value. If the $D SPOOLDEF DSNMASK value is null, the DSNAME value must match the $D SPOOL DSNAME value.

Modification: Cold start.

FENCE=(ACTIVE=YES|NO[,VOLUMES=nnn|1])

ACTIVE= Determines if any fencing is active at the time.

VOLUMES= Specifies the the number of volumes a job will be fenced to.

Note:

Setting FENCE=(ACTIVE=YES,VOLUMES=1) will cause JES2 to function as it did previously with FENCE=YES. For compatibility, the code will allow FENCE=YES and convert it to ACTIVE=YES and VOLUMES=1.
See z/OS JES2 Installation Exits for a discussion of how this initialization statement relates to Exit 11, $TRACK and Exit 12, $STRAK.

Modification: $T SPOOLDEF operator command. This parameter cannot be changed on a warm start.

SPOOLNUM=nnn|32

Specifies the maximum number (1-253, rounded up to a multiple of 32 or 253) of spool volumes which can be defined at any one time to a multi-access spool complex. Spool volumes are defined by either use of the VOLUME= parameter on this initialization statement during a JES2 cold start, or they can be defined by using the $S SPL (start spool) operator command. This parameter can be increased with a $T SPOOLDEF command after an $ACTIVATE command has been issued in the MAS.

Note:

If you specify other than a multiple of 32 volumes, JES2 automatically rounds that value up to a multiple of 32. Also, a $D SPOOLDEF command will display the JES2-defined (rounded-up) value, not the value specified here if that value was not a multiple of 32.
A value for SPOOLNUM= of 254-256 is automatically decreased to 253 by JES2.
To avoid a future cold start, set this value to a value greater than your current requirements dictate and use the $S SPL command to start volumes, as required.

Performance Considerations: As you set this parameter to values greater that 32, storage in the JES2 address space is used accordingly. For each additional 32 volumes specified, the JQE control block is increased by 4 bytes; these bytes are required for the JQE spool volumes-used mask.

Modification: $T SPOOLDEF operator command or JES2 cold start to decrease.

LARGEDS=FAIL|ALLOWED|ALWAYS

Specifies whether large SPOOL data sets (greater than 65,535 tracks) can be started or not. Also, indicates when to use the new format SPOOL record addresses (MTTRs).

FAIL: Specifies any attempt to start a SPOOL data set with more than 65,535 tracks is to fail.
ALLOWED: Specifies that SPOOL data set with up to the current size limit (1,048,575 tracks) is allowed. New format SPOOL addresses are used when starting a new volume that contains a SPOOL data set with greater than 65535 tracks.
ALWAYS: Processing is the same as ALLOWED, except the new format SPOOL addresses are used when stating any volume, regardless of data set size. This setting is intended for testing applications that may use SPOOL addresses to access records on SPOOL when an actual large data set is not available.

Note:

When LARGEDS is set to ALLOWED or ALWAYS, JES2 members at levels earlier than z/OS® V1R7 can join the MAS until a COLD start is performed. IBM® suggests not setting LARGEDS to ALLOWED or ALWAYS until all MAS members have stabilized on a z/OS release 7 level of JES2 or later.
Even if LARGEDS is set to ALLOWED or ALWAYS, SPOOL volumes with more than 15 records per track (for example, when using buffer sizes less than 2943 on a 3390) cannot use the new format for SPOOL record addresses, and do not support data sets larger than 65535 tracks.
LARGEDS=FAIL is not supported in z11 mode. In z11 mode, on a COLD start, JES2 defaults to LARGEDS=ALLOWED; on all other starts, it defaults to the value that was used when JES2 shut down. If LARGEDS=FAIL is specified on a COLD start, the default value of ALLOWED will be used.

Modification: $T SPOOLDEF operator command or JES2 cold start.

TGSIZE=nnn|30

Specifies the number (1-255) of JES2 buffers to be contained in a track group. JES2 uses this value to determine the number of tracks in a track group on each spool device. This is the default value for the number of track groups for each new spool volume added to the complex. Because the number of tracks in a track group will vary based on the track capacity of the device, the resultant value is rounded to the minimum integral number of tracks that can contain the specified number of buffers.

If you specify TGSIZE=, it must contain a value from 1 to 255. Regardless of the value specified, the minimum resulting track group size is one track and the maximum is the smaller of 255 and the number of tracks in the first extent of the SYS1.HASPACE data set with the least number of tracks.

Note: If you do not specify TGSIZE= as the same value on all members of the complex, JES2 might not use the value specified here for a new spool volume.

Performance Considerations: Attempt to tailor the value of TGSIZE to fit the majority of the jobs in your system. SMF type 26 records can be used to assist your choice of a value for this parameter.

Small values for TGSIZE= can cause an excessive number of track group allocations per job thus increasing processor overhead. For example, an IEFBR14 job requires 13 spool buffers for control blocks and JCL data sets; therefore, set the value of TGSIZE= greater than 13. Large values for TGSIZE= can waste spool space and unnecessarily increase seek time.

Modification: Minimum action to modify is $T SPOOLDEF to increase and a JES2 cold start to decrease.

TGSPACE=(MAX=nnnnnnnn|16288[,WARN=nnn|80])

MAX= specifies the maximum number (1-132649472) of track groups required before the next cold start. This value should include the track groups for all concurrently mounted spool volumes and for all planned spool additions when determining each spool volume's requirement. Specify TGSPACE=(MAX=) as a multiple of 16288. If you do not, JES2 will automatically increase your specification to the next highest multiple of 16288 without returning a message. Therefore, if you display the SPOOLDEF parameters by the $D SPOOLDEF command, the value returned by JES2 will not match the value originally specified here.

Note: If the number of track groups you have allocated on each spool volume is not divisible by 8, there will be a discrepancy between the maximum allocatable track groups and the sum of the allocated track groups plus the number of track groups available.

Note:

Use this parameter to increase the limit for the JNUM resource that is reported on the HASP050 message. End of change

Table 1 lists the number of track groups per volume for various devices:

Table 1. The Number of Track Groups per Volume Listed by Device Type (and TGSIZE=30)
DEVICE	BUFSIZE	CYL/VOL	TRKS/GRP*	TRACK GRPS/VOL*
3390-3	3992	3339	3	16690
3390-9	3992	10017	3	50080
* This assumes the default TGSIZE=30 was used. See z/OS JES2 Initialization and Tuning Guide for further statistics relating to the specification of this parameter and resultant DASD utilization. Note: Assume that cylinder 0 is not available; it is used to hold the VTOC.

Performance Considerations: The should consider future spool volume additions. nnnnnnn should be large enough to accommodate planned expansion; therefore, set this parameter significantly higher than your present requirements dictate. The performance cost should be minimal; storage is calculated as follows:

((((nnnnnnn + 16287) / 16288) x 16288) / 8) x 4

The values chosen for this parameter, BUFSIZE= and TGSIZE= (as specified on this initialization statement), are related and thus all affect efficient use of spool devices. (See z/OS JES2 Initialization and Tuning Guide for selected values that affect spool device utilization and for selected values that affect device utilization in storage-constrained environments.)

If you do not specify a value, this parameter defaults to 16288 (This is the number of track groups needed to allow all three track groups (master, JES2-detected badtracks, and the BADTRACK statement-specified tracks) to efficiently fit on one page of storage.

If you use the $T SPOOLDEF command to increase TGSPACE=(MAX=), only do so when you can allow your system to experience temporary performance degradation while all JES2 systems read the checkpoint data set.

WARN= specifies a percentage (1-99) threshold of track groups usage that triggers message $HASP050 JES2 RESOURCE SHORTAGE. The WARN= percentage is calculated only from spool volumes that are active and can have space allocated (ACTIVE and RESERVED=NO).

Modification: $T SPOOLDEF operator command to increase, or using a cold start. A JES2 cold start must be used to decrease.

Note: This parameter cannot be modified through a hot start, quick start, or single-member warm start.

TRKCELL=nnn|3

Specifies the size (1-120) of a track cell in terms of spool buffers; that is, TRKCELL= specifies the number of direct-access spool records to be logically ordered on a spool track and the number of records to be despooled (read from the spool) in one operation during print processing. A data set will use the track-cell method only if the SYSOUT class of the data set has the TRKCELL= characteristic; see the description of the OUTCLASS(v) initialization statement. Similarly, track cells, rather than single buffers, are despooled during print processing only if the printer is defined with the TRKCELL=YES parameter on the PRTnnnn statement (see the description of the PRTnnnn initialization statement in this chapter ).

If TRKCELL= is greater than the number of records on a track of a spool volume, the entire track is considered a track cell. If TRKCELL= is less than or equal to the number of records on a track of a spool volume, the track is divided into as many track cells as will fit evenly. For further information, see z/OS JES2 Initialization and Tuning Guide.

After this division, any remaining records are used as follows:

If the number of remaining records is greater than or equal to one-half the TRKCELL= value, the records are available to any data set (with or without the track-cell characteristic).
If the number of remaining records is less than one-half the TRKCELL= value, the records are available only for data sets without the track-cell characteristic.

Performance Considerations: The following performance specification considerations should be noted when defining a value for TRKCELL=.

In the NJE environment, the SYSOUT receiver flags the data sets in a class (with TRKCELL= specified on the OUTCLASS statement) it receives with the TRKCELL= attribute. To avoid degraded performance when printing these data sets on a printer which supports track-cell despooling (TRKCELL=YES parameter on the PRTnnnn statement), the TRKCELL= specification should be selected to prevent spool tracks from containing “short” track-cells (that is, those track-cells with a length less than half TRKCELL=).
Print buffers typically reside in central storage during JES2 printing and despooling operations. Therefore, a large value for TRKCELL= increases JES2 central storage requirements.

Modification: Cold start.

Volume=xxxxx|SPOOL

Specifies the 4- to 5-character prefix assigned to JES2's spool volumes. The first four to five characters of the volume serial must be identical to the characters specified by this parameter. Those volumes beginning with this prefix and a data set named the same as the DSNAME specification are considered JES2 volumes.

The maximum number of spool volumes in use by JES2 must not exceed 253 at any one time.

IBM suggests that you limit the prefix to 4 characters only so that you are not restricted to a maximum of 39 volumes as is the case if you use a 5-character prefix which also limits the suffix to a single character (A-Z, 0-9, $, #, @). This will help you avoid future cold starts.

Modification: Cold start. If originally specified with 5 characters and the fifth character is removed, then $T operator command is allowed.