1 02/28/85 system_link_meters
 2 
 3 Syntax as a command:  system_link_meters {-control_arg}
 4 
 5 
 6 Function:  prints out system-wide statistics regarding usage of the
 7 Multics linker.  Information is obtained from the active_hardcore_data
 8 and tc_data data bases.
 9 
10 
11 Control arguments:
12 -report_reset, -rr
13    generates a full report and then performs the reset operation.
14 -reset, -rs
15    resets the metering interval for the invoking process so that the
16    interval begins at the last call with -reset specified.  If -reset
17    has never been given in a process, it is equivalent to having been
18    specified at system initialization time.
19 
20 
21 Access required:  This command requires access to phcs_ or
22 metering_gate_.
23 
24 
25 Notes:  If the system_link_meters command is given with no control
26 argument, it prints a full report.
27 
28 Statistics are given for overall use of the linker, and are also broken
29 down by task.  The three major tasks of the linker are listed below.
30 
31 1. Searching the definition section of the object segment for the
32    symbolic name of the referenced segment.
33 
34 2. Searching for the segment using the standard search rules.
35 
36 3. Getting the linkage to the referenced segment.
37 
38 
39 The following are brief descriptions of the variables printed out by
40 the system_link_meters command.
41 CPU Metering time
42    is the amount of time for which the processor was busy.  It equals
43    total processor time minus idle time.
44 Total time in linker
45    is the total amount of CPU time spent in the linker, expressed as
46    hh:mm:ss.
47 Average time per link
48    is the average time to completion (in milliseconds) for a call to
49    the linker.
50 Percentage of real time in linker
51    is the percentage of total metering time that was spent in the
52    linker.
53 
54 
55 Percentage of CPU
56    is the percentage of virtual CPU metering time that was spent in the
57    linker.
58 Time Slot
59    are the time slots into which calls to the linker are broken down.
60    The four slots are for calls completed in less than 25 milliseconds,
61    calls completed in between 25 and 50 ms, calls completed in between
62    50 and 75 ms, and calls completed in more than 75 ms.
63 Calls
64    is the number of calls that were completed in each time slot.
65 Total time in slot
66    is the total amount of virtual CPU time taken by calls in each time
67    slot.
68 
69 
70 Percent total time
71    is the percentage of the virtual CPU time spent in the linker that
72    was taken by calls in each slot.
73 Percent total calls
74    is the percentage of calls to the linker that fell into each time
75    slot.
76 Average time
77    is the average time (in milliseconds) to complete a call to the
78    linker that ended up in each time slot.
79 Average page faults
80    is the average number of page faults for a call in each slot.
81 
82 
83 The following statistics are given for each of the three major tasks of
84 the Multics linker:  definition search, segment search, and get
85 linkage.
86 Average time
87    is the average time (in milliseconds), for a call in each slot,
88    spent on that particular function of the linker.
89 Average page faults
90    is the average number of page faults for a call in each slot, which
91    occurred during that particular task of the linker.
92 Percent time in slot
93    is the percentage of the total time spent in the slot that was taken
94    up by that particular task.  These percentages do not add up to 100%
95    because some time used by the linker does not fit into any of the
96    three categories.