Technical data

Managing User Accounts
7.11 Managing System Resources
Table 7–9 (Cont.) Descriptions of SYSTEM and DEFAULT Accounts
Account Description
Buffered I/O Count
Limit (BIOlm)
Limits the number of outstanding buffered I/O operations permitted for a user’s
process.
In a buffered I/O operation, the data transfer takes place from an intermediate
buffer in the system pool, not from a process-specified buffer. Buffered operations
for a user process include terminal I/O, file system and network I/O, card reader
input, and unspooled printer output. During a buffered I/O operation, the pages
containing the process-specified buffer need not be locked in memory.
Buffered I/O Byte
Count Limit (Bytlm)
Limits the amount of buffer space that a user’s process can use.
This buffer space is used for buffered I/O operations and for the creation of
temporary mailboxes. It also limits the number of mapping windows the user can
create as segmented (or cathedral) windows. Cathedral windows are primarily
useful for reducing the overhead required to read large files.
CPU Time Limit
(CPU)
Limits the amount of CPU time that a user’s process can use per session.
The time must be specified in abbreviated delta format hh:mm:ss.cc.
CPU is a deductible limit with a suggested typical value of 0 (no limit) but the
value applies only to this instance or to other instances of the user’s processes.
CPU is not cumulative across separate sessions or batch jobs.
Direct I/O Count
Limit (DIOlm)
Limits the number of outstanding direct I/O operations permitted to a user’s
process.
In a direct I/O operation, the data transfer takes place directly from a process-
specified buffer. Direct I/O operations for a user process typically include disk and
tape I/O. The pages containing this buffer are locked in memory by the operating
system during the direct I/O operation.
DIOlm is a nondeductible limit.
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7–44 Managing User Accounts