The SYS1.PARMLIB IGDSMSxx
member includes several parameters that
support the coupling facility. With the exception of RLSINIT, these
parameters apply across all systems in the Parallel Sysplex®. The
parameter values specified for the first system that was activated
in the sysplex are used by all other systems in the sysplex.
The
following SYS1.PARMLIB IGDSMSxx member parameters support VSAM
RLS:
- CF_TIME
- DEADLOCK_DETECTION
- RLSINIT
- RLS_MaxCfFeatureLevel
- RLS_MAX_POOL_SIZE
- RlsAboveTheBarMaxPoolSize
- RlsFixedPoolSize
- SMF_TIME
You can change the values for these
parameters during VSAM RLS processing only when all the spheres
are closed .
The new values are then used by all systems in the Parallel Sysplex, except
for RLSINIT parameter values which are used only by the system accessing
the changed parmlib member when SMSVSAM is next started.
To
change the values of these parameters, use one of the following
methods:
- Issue the SETSMS operator command, specifying the parameter
with
different values.
- Issue the T SMS=xx command,
where xx identifies
an IGDSMSxx member where the parameter values are different than those
currently in use.
The following list describes the
parameters and their values:
- {CF_TIME(nnn|3600)}
- Indicates the number of seconds between
recording SMF type 42
records with subtypes 15, 16, 17, 18, and 19 for the CF (both cache
and lock structures). You can specify a value from 1 to 86399 (23
hours, 59 minutes, 59 seconds). The default is 3600 (one hour).
This
keyword sets the interval time for the following SMF 42 subtypes:
- SUBTYPE 15
- CF storage class average response
time
- SUBTYPE 16
- CF data set average
response time
- SUBTYPE 17
- CF lock
structure activity
- SUBTYPE 18
- CF
cache partition summary
- SUBTYPE 19
- SMSVSAM
least recently used statistics summary
- {DEADLOCK_DETECTION(iiii|15,kkkk|4)}
- Specifies the deadlock detection
intervals used by the Storage
Management Locking Services.
- iiii
- specifies
the length in seconds of the local deadlock detection
interval, as a one to four digit numeric value in the range 1-9999.
The default is 15 seconds.
- kkkk
- specifies the number of local deadlock cycles that must expire
before global deadlock detection is run, as a one to four digit numeric
value in the range 1-9999. The default is 4 cycles.
- [RLSINIT({NO|YES})]
- Specify YES if you want the SMSVSAM
address space started as
part of system initialization or the V SMS,SMSVSAM,ACTIVE command.
This value applies only to the system accessed by the parmlib member
and is acted upon when SMSVSAM is next started. The default is NO.
- [RLS_MaxCfFeatureLevel({A|AMx|Z})]
- Specifies the method that VSAM RLS
uses to determine the size
of the data that is placed in the CF cache structure.
If you specify A,
caching proceeds using the RLSCFCACHE keyword characteristics that
are specified in the SMS data class that is defined for the VSAM sphere.
With feature level A the user can also specify Mx values
in the form of AMx to customize IGW500I messages for open spheres
as follows:
- M0
- IGW500I messages for all open spheres
will be suppressed.
- M1
- IGW500I
messages for all open spheres will be displayed.
- M2
- Only for the first sphere opened in the sysplex will
an IGW500I
message be displayed.
- M3
- IGW500I
messages for all open spheres in the sysplex will be
sent to hardcopy.
- M4
- Only for the
first sphere opened in the sysplex will an IGW500I
message be sent to hardcopy.
If you do not specify a value, or if you specify Z,
then only VSAM RLS data that have a Control Interval (CI) value of
4K or less are placed in the CF cache structure. The default is Z.
Restrictions: The
restrictions are described below.
- If A is specified for the RLS_MaxCfFeatureLevel
parameter,
systems lower than z/OS® V1R3
will not be able to connect to the CF cache structure.
- If
a lower-level system is the first system activated in the sysplex,
RLS_MaxCfFeatureLevel defaults to Z, and
all systems will
be able to connect to the CF cache structure.
- If the SETSMS
command is used to change the RLS_MaxCfFeatureLevel
value to A on a mixed-level system, the
command is rejected
and message IGW500I is issued.
- The Mx modifier can only be
combined with feature
level A in the form of AMx, otherwise an IGW467I will be issued to
indicate that the Parmlib value specified is not valid.
- If
the SETSMS command is used to change the RLS_MaxCfFeatureLevel
value to Z when there are VSAM spheres assigned
to cache
structures, the command is rejected and message IGW500I is issued.
- [RLS_MAX_POOL_SIZE({nnnn|100})]
- Specifies the maximum size in megabytes
of the SMSVSAM local
buffer pool. SMSVSAM attempts to not exceed the buffer pool size
you specify, although more storage might be temporarily used. Because
SMSVSAM manages buffer pool space dynamically, this value does not
set a static size for the buffer pool.
Use SMF 42, subtype 19 records
to help you determine the maximum size of the SMSVSAM local buffer
pool.
You can specify a two to four-digit numeric value, with
10 as the minimum value. If you specify a value less than 10, the
field is set to 10. If you specify a value greater than 1500, SMSVSAM
assumes there is no maximum limit. We recommend that you limit the
size of the local buffer pool.
The default is 100
MB.
- [RlsAboveTheBarMaxPoolSize{( sysname,
maxrls; ...)|(ALL,maxrls}]
- Specifies the maximum amount of virtual
storage above the 2-gigabyte
bar that can be used for VSAM RLS buffering in a system in the sysplex,
where:
- sysname identifies a system and maxrls is
specified
in megabytes for that system. Multiple sets of sysname,
maxrls pairs
may be specified, separated by semicolons.
- (ALL,maxrls) specifies
that each system
in the sysplex will have the same specified value.
The default
for maxrls is 0, and the specifiable values
are 500 to 2000000 (that is, 500MB to 2 terabytes).
- [RlsFixedPoolSize{( sysname,
maxrls; ...)|(ALL,maxrls}]
- Specifies the total amount of real
storage (both above and below
the 2-gigabyte bar) to be dedicated to VSAM RLS buffering in a system
in the sysplex, where:
- sysname identifies a system and maxrls is
specified
in megabytes for that system. Multiple sets of sysname,
maxrls pairs
may be specified, separated by semicolons.
- (ALL,maxrls) specifies
that each system
in the sysplex will have the same specified value.
The default
for maxrls is 0, and the specifiable values
are from 0 to 80% of the total unpinned available real storage. When
80% is reached, the RLS address-space SMSVSAM Initialization will
issue a message to warn of the limit.
- [SMF_TIME({YES|NO})]
- Specifies
that the following SMF type 42 records are created
at the SMF interval time, and that all of the indicated records are
synchronized with SMF and RMF data intervals.
- SUBTYPE 2
- Cache control unit
statistics (IBM® 3990-3,
3990-6, IBM RVA, and IBM ESS)
- SUBTYPE
15
- Coupling facility storage class average response time
- SUBTYPE 16
- Coupling facility data set
average response time
- SUBTYPE 17
- Coupling
facility lock structure activity
- SUBTYPE
18
- Coupling facility cache partition summary
- SUBTYPE 19
- SMSVSAM least recently used statistics
summary
This allows the customer to merge these
SMF records for a specified
time period and obtain both the 'system' view and the 'user' view
of activity in the interval.
YES is the default. DFSMS creates
the specified SMF record when the interval period expires and SMF
sends the event notification signal.
If you specify
YES, SMF_TIME overrides the following IGDSMSxx parameters: CACHETIME,
CF_TIME.