Technical data

Managing User Accounts
7.11 Managing System Resources
In most cases, Alpha systems present to users, and accept from users, units
of memory in a 512-byte quantity called a pagelet. Thus, one pagelet is the
same size as one VAX page. Also, on an Alpha 8KB computer, 16 pagelets equal
1 Alpha page. The following conversion table shows the relationship between
pages, pagelets, and bytes:
One Alpha pagelet = one VAX page = 512 bytes
One Alpha page = 16 Alpha pagelets = 16 VAX pages = 8192 bytes
Authorize utility commands, parameters, and default values are identical.
However, the default values for process quotas related to memory use might be
inappropriate for some Alpha system users.
See A Comparison of System Management on OpenVMS AXP and OpenVMS VAX
for more information about Alpha system management. (This manual has been
archived but is avalable on the OpenVMS Documentation CD-ROM.)
7.11.2 Setting Limits on System Resources
Each system user is limited in the consumption of such resources as system
memory, volatile (pagefile) disk space, number of processes, and I/O requests. You
set limits when you create an account for the user with the Authorize utility.
Limits control the way in which a process shares its allotment of a resource with
the subprocesses it creates. In addition to restricting the number of processes
that a single user or account has at any given time, the system uses four types of
limits for sharing resources. Table 7–1 describes these limits.
When you create an account, you assign values to the limits shown in Table 7–8.
These limits are described in the following sections. Usually, you simply assign
the default values for these limits. However, see the OpenVMS Performance
Management for a discussion of how to evaluate and adjust the limits in the
context of performance optimization strategies.
Table 7–8 summarizes each of these limits, the value supplied in the UAF record
for the SYSTEM and DEFAULT accounts, and the type of limit.
Table 7–8 Limits and Suggested Values for SYSTEM and DEFAULT Accounts
Limit
VAX
SYSTEM
Value
VAX
DEFAULT
Value
Alpha
SYSTEM
Value
Alpha
DEFAULT
Value Type
1
Description
ASTlm 50 0 250 250 N AST queue limit
BIOlm 40 40 150 150 N Buffered I/O count limit
Bytlm 32768 32768 64000 64000 P Buffered I/O byte count
limit
CPU 0 0 0 0 D CPU time limit (0 = no
limit)
DIOlm 40 40 150 150 N Direct I/O count limit
Enqlm 300 200 2000 2000 P Enqueue quota
Fillm 300 300 100 100 P Open file limit
1
D=deductible, N=nondeductible, P=pooled, S=systemwide
(continued on next page)
7–42 Managing User Accounts