1 02/28/85 sweep_pv
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3 Syntax as a command: sweep_pv pvname -control_args
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5
6 Function: performs utility functions that require walking through the
7 VTOC of a mounted physical volume. Among these functions are the
8 listing of contents and unconnected VTOCEs, the deletion of such
9 VTOCEs, and the evacuation of physical volumes for logical volume
10 compression. The volume is processed in VTOC order.
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12
13 Arguments:
14 pvname
15 is the name of the mounted physical volume whose VTOC is to be
16 walked through.
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18
19 Control arguments:
20 -adopt
21 attempts to reconstruct directory branches for VTOCEs encountering
22 reverse connection failures. Unique names are derived from the
23 primary name in the VTOCE. The -gc control argument must be given
24 to use the -adopt control argument. If the -dl control argument is
25 given as well, VTOCEs that cannot be adopted are deleted. The
26 success or failure of adoptions is reported to the report produced
27 by the -gc control argument. For a description of the definition
28 attributes provided for adopted branches, see the description of the
29 adopt_seg command. This request requires hc_backup_ access.
30 -debug, -db
31 is for system programmer use, and disables highly privileged calls
32 in order to allow debugging of this program.
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34
35 -delete, -dl
36 deletes unconnected VTOCEs. This control argument is only allowed
37 when the -gc control argument is specified. Access to hphcs_ is
38 required to use this control argument. The collection report is
39 modified to indicate that these VTOCEs were deleted.
40 -force, -fc
41 forces access to all directories that need to be scanned where
42 status permission is lacking. Status permission is necessary for
43 all components of the pathnames of VTOCEs processed. If this
44 control argument is not used, or status permission is lacking and
45 cannot be forced, an error is reported.
46 -from first
47 indicates the first VTOCE to be processed. If first is not given,
48 VTOCEs are processed starting at VTOC index 0.
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50
51 -gc
52 performs garbage collection, i.e., all VTOCEs for which a reverse
53 connection failure is encountered in resolving their pathnames are
54 logged in a collection file. This file is produced whether or not
55 the -list control argument, above, is specified. At the end of the
56 collection file report, the total number of VTOCEs and records held
57 by them in this state is printed. Selected information, such as the
58 name in the VTOCE and date/time used and modified, is also put in
59 the report for each such VTOCE. The collection file report is given
60 a three-component name and is placed in the working directory. The
61 three-component name has "pvgc" as the first component, the physical
62 volume name as the second, and the time the segment is created as
63 the third component e.g. pvgc.public.0814.
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65
66 -list
67 creates a listing file containing the VTOC index, time listed, and
68 pathname of every segment on the volume at the time its VTOCE is
69 scanned. An asterisk on the line of the listing for a particular
70 VTOCE indicates a reverse connection failure i.e. no branch exists
71 for the entry. For nondirectory segments, the page fault meter of
72 the segment is given. The convention for listing incomplete
73 pathnames is the same as that used by the vtoc_pathname command see
74 the vtoc_pathname description in the Multics Commands and Active
75 Functions manual Order No. AG92. The listing file is given a
76 three-component name and is placed in the working directory. The
77 three-component name has "pvlist" as the first component, the
78 physical volume name as the second, and the time the segment is
79 created as the third component e.g. pvlist.public.0749.
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81
82 -move, -mv
83 moves all segments corresponding to VTOCEs processed off this volume
84 onto another physical volume of the same logical volume. Segments
85 that suffer reverse connection failures are not moved. If segments
86 are moved for some purpose other than evacuation, the inhibit_pv
87 command should be invoked with the -off control argument after
88 moving has taken place. The sweep_pv command attempts to target
89 segment moves to the physical volume in the logical volume with the
90 most page space available by inhibiting and disinhibiting volumes
91 dynamically; all volumes except the volume being evacuated are
92 disinhibited when the sweep_pv command is exited. Volumes found to
93 be inhibited at the time the command is invoked are not
94 disinhibited; this facilitates simultaneous evacuation of volumes.
95 Any volume that is completely evacuated by this means should be
96 deregistered before the logical volume is reaccepted. Access to the
97 hphcs_ gate is required to use this control argument. See the
98 Multics System Maintenance Procedures manual Order No. AM81 for
99 more details.
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101
102 -only vtocx
103 processes only the single VTOCE whose octal index is vtocx.
104 -to last
105 indicates last VTOCE to be processed. If last is not given,
106 processing proceeds to the end of the VTOC.
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108
109 Access required: The sweep_pv command requires phcs_ access, access to
110 hc_backup_ if the -adopt control argument is used, and access to hphcs_
111 if the -delete or -move control arguments are used.
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113
114 Notes: Any errors encountered during the VTOC sweep are reported to a
115 file that is given a three-component name and placed in the working
116 directory. The three-component name has "pvef" as the first component,
117 the physical volume name as the second, and the time the segment is
118 created as the third component e.g. pvef.public.1321. Errors in
119 command usage, such as specifying a nonexistent or unmounted physical
120 volume, are reported to the bootload console.
121
122 When sweep_pv is invoked with the -move control argument, it first
123 inhibits segment creation on the volume being vacated, and then vacates
124 the pack. When sweep_pv terminates, it leaves the volume inhibited and
125 prints a message to this effect. The volume can be uninhibited
126 manually by means of the inhibit_pv command.