資料來源 : Free On-Line Dictionary of Computing
process table
A table containing all of the
information that must be saved when the {CPU} switches from
running one {process} to another in a {multitasking} system.
The information in the process table allows the suspended
process to be restarted at a later time as if it had never
been stopped. Every process has an entry in the table. These
entries are known as {process control blocks} and contain the
following information:
process state - information needed so that the process can be
loaded into memory and run, such as the {program counter}, the
{stack pointer}, and the values of {registers}.
memory state - details of the memory allocation such as
pointers to the various memory areas used by the program
resource state - information regarding the status of files
being used by the process such as {user ID}.
Accounting and scheduling information.
An example of a UNIX process table is shown below.
SLOT ST PID PGRP UID PRI CPU EVENT NAME FLAGS
0 s 0 0 0 95 0 runout sched load sys
1 s 1 0 0 66 1 u init load
2 s 2 0 0 95 0 10bbdc vhand load sys
SLOT is the entry number of the process.
ST shows whether the process is paused or sleeping (s), ready
to run (r), or running on a {CPU} (o).
PID is the {process ID}.
PGRP is the {process Group}.
UID is the {user ID}.
PRI is the priority of the process from 127 (highest) to 0
(lowest).
EVENT is the {event} on which a process is paused or
sleeping.
NAME is the name of the process.
FLAGS are the process {flags}.
A process that has died but still has an entry in the process
table is called a {zombie process}.
(1998-04-24)