as that of the INDICATE USER * option. For detailed discussion
of the class G INDICATE command, see fo£ QUEUES displays the active users, the queues that they are in, the
storage that they are occupying, and the status that they are
in. The display indicates those users currently dominating main storage. Users waiting in eligible lists are included in the
response because they are contending for main storage and it is
only by chance that they were not occupying main storage at the
time of the command. I/O provides information about conditions leading to possible
contention within the system. The response gives the userids of
all the users in I/O wait state at that instant in time, as well
as the address of the real device to which the most recent virtual SIO was mapped. The response, however, does not show
the queue of users who issue SIOF to busy devices. Because the
response indicates only an instantaneous sample, use the command
several times before assuming a condition to be persistent. If
it is persistent, use the SEEKS operand of the MONITOR command
to conduct a thorough investigation of the suggested condition.
PAGING WAIT is provided for installations that have 2305s as primary paging
devices and other direct access devices as secondary paging
devices. A full primary device and subsequent allocation of
paging space on the slower device may be responsible for
degradation of the system's performance. Use the PAGING WAIT operand when the QUEUES operand shows that a significant
proportion of the users in queue 1 and queue 2 are persistently
in page wait. The response to the command gives the userids of
those users currently in page wait and the number of page frames allocated on drum storage and on disk storage.
PAGING ALL
displays the page residency data of all users of the system (including the system nucleus and pageable routines). The
format of the reply message is identical to that of the PAGING WAIT operand ..
The intent of the INDICATE command is twofold:
1. Provide the operator with a "snapshot" of system activities.
2. Provide a means of determining the execution characteristics of a
program with respect to the resources it uses.
In respect to the latter, INDICATE USER should be invoked before and
after the execution of a program. If the INtICATE USER command is
issued during the execution of the subject program and the program is
issuing spooling I/O requests, the may questionable. The
reason this occurs is that S08e fields (specifically, the PCB=nnnnnnn,
PTR=nnnnnn and RDR=nnnnnn fields) in the response to the INDICATE USER co •• and are once (either at the beginning or at the end of an
operation). Other fields in the response are uFdated more dynamically. Consequently, you should avoid to halting or aborting any spooling
operation before its normal termination if the INDICATE USER command is
to be issued. Section 3. CP Commands 81
CPU-nnn% APU-nnni Q1-nn Q2-nn STORAGE-nnni RATIO-nn.n CPU-nnni APU-nnni is a smoothed value that indicates the percentage of time that
the system is running in the main processor.
is a smoothed value that indicates the rercentage the attached processor is running.
of time that
Q1-nn Q2-nn
indicates the contention for CP is represented
values of the numbers of users in queue 1 and
values are maintained by the scheduler. STORAGE-nnni by smoothed queue 2. The
is a measurement of the use of real storage. It is a smoothed
ratio of the sum- of the estimated working sets of the users in
queue 1 and queue 2 to the number of pageable pages in the
system, expressed as a percentage. Because the criterion for
allowing a user on the eligible list to enter a queue is that at
least 15 percent of his working set size must fit in the
available page frames, the value of STORAGE can be more than 100 percent.
RATIO-nn.n
indicates the scheduler contention ratio; RATIO is a smoothed measure of the contention for real storage, and is defined as RATIO=(E.ft)/M. K is the number of users in queue 1 and queue 2
and E is the number of users waiting to be allocated real
storage by the scheduler and, therefore, temporarily resident in
the scheduler's eligible lists. Thus, RATIO is the ratio of
active users to users being serviced, and is 1.0 for optimum response. Optimum response occurs when storage is
available to accommodate all active users, assum1ng the CPU can -'pro'ces's---t-heir· If---Y" 'inra--·1!--ar-e-- -1:Hftll---O-;--tlie--'" vaTtfe "·of- RATIO is set to 1.0. Values of RATIO=1.5 and ft=10, mean that
users are in the eligible lists waiting for the scheduler to
allocate real storage space to them and the full discrimination
ability of the biased scheduler may be exercised upon them.
r , 1* I I userid I L -' PAGES: RES-nnnn WS-nnnn READS=nnnnnn WRITES=nnnnnn DISK-nnnn DRUft-nnnn YTIftE=nnn:nn TTlftE=nnn:nn SIO=nnnnnn RDR-nnnnnn PRT-nnnnnn PCH-nnnnnn The first line of the response gives all the data from the user's VMBLeK tbat is relevant to his virtual .achine's paging activity and resource
occupancy.
n is a decimal number throughout. RlS is the current number of the user's virtual storage pages
resident in real storage at the time the command is issued. is is the most recent system estimate of the user's working set
size.
82 VM/370 Operator's Guide
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