Not To Be Reproduced 5-5 FaQA
DIRECTORY CONTROL DATA BASES
DIRECTORY SEGMENT STRUCTURE
Not To Be Reproduced 5-6
HASH TABLE
6
F8QA
DIRECTORY CONTROL ~ BASES DIRECTORY SEGMENTS
• DIRECTORY SEGMENTS ARE DISK RESIDENT (RLV) DATA BASES MAINTAINED BY DIRECTORY CONTROL
o ONE DIRECTORY SEGMENT PER DIRECTORY IN THE HIERARCHY
• ,DIRECTO~YSEGMENTS C,ONTAIN. "', . CATALOG ,OF STORAGE SYSTEM I~FORMATION ,'; ~ABOUT':OTHER 'SEGMENT'S, ,DlRECTORIES'AND'LINKS""'
• ALL-DIRECTORY' SEGMENTS, BY CONVENTION, RESIDE ON THE ROOT LOGICAL VOLUME (RLV)
• DIRECTORY SEGMENTS ARE CREATED BY append MUCH LIKE NORMAL SEGMENTS ARE CREATED
• DIRECTORY SEGMENTS CONTAIN MANY INTER-RELATED COMPLEX DATA STRUCTURES TO INCLUDE THE FOLLOWING (NOT NECESSARILY CONTIGUOUS) REGIONS:
D DIRECTORY HEADER' '
o CONTAINS SELF DESC~IPTlVE INFORMATION LIKE UID, AIM CLASSIFICATION, ETC; AND POINTERS TO OTHER REGIONS
Not To Be Reproduced 5-7 F8QA
DIRECTORY CONTROL DATA BASES DIRECTORY SEGMENTS
HASH TABLE
n USED TO QUICKLY LOCATE AN ENTRY, GIVEN ITS NAME
ENTRY LIST
D CONTAINS ONE DESCRIPTIVE DATA STRUCTURE (AN ENTRY) FOR EACH SEGMENT, DIRECTORY, ·OR LINK. IMMEDIATELY INFERIOR TO THE DIRECTORY (I~E. -ALL ENTRIES)
PERSON_ID AND PROJECT_ID NAME LISTS
n CONTAINS ·ALL PERSON_ID'S/PROJECT_ID'S REQUIRED TO DESCRIBE THE ACL, THE AUTHOR, ETC. OF ALL SEGMENTS AND DIRECTORIES
IMMEDIATELY INFERIOR TO THE DIRECTORY (I.E. ALL BRANCHES)
D NAME LIST (ONE PER ENTRY)
1
CONTAINS ALL NAMES CURRENTLY ASSIGNED TO THE ENTRY
PRIMARY NAME IS ACTUALLY CONTAINED IN ENTRY STRUCTURE ITSELF
n ACCESS CONTROL LIST (ONE PER ENTRY)
n CONTAINS ALL ACL ENTRIES CURRENTLY ASSOCIATED WITH THE ENTRY
Not To Be Reproduced 5-8 F8QA
o
DIRECTORY CONTROL DATA BASES DIRECr9RY HEADER ENTRY 1.IST START R_PTA
NUMBER OF SCG ENnUiS
6 WORDS USED BY SAL VAGt:R FOR Rt:COROING OA Ti TIME CHECXED AND ERRORS DISCOVERED
DIRECTOR" UNIQUE IDENTlFIER (UJOI DIRECTORY'S PHYSICAL VOLUME 10 (PVIO) SONS" LOGICAL VOLUME 10 (LVIO)
ACCISS ISOLATION MECHANISM (AlMt CUSS
*
HEADER VERSION NUMBERPROJECT -'0 LIST START R.JTR PROJECT _10 LIST END R _PTA NUMBER OF OIR ENTRiES
NUMBER OF UNK ENTRIES NUMBER OF ACL ENTRIES
ALLOCATION AREA R _PTA
24WORDSUSCD FOR INITIALAC1.IMPLeMENTATION
HASH TABLE SIZE
NUMBER OF USED PLACES IN HASH T ASLE DEPTH OF THIS DIRECTORY
OATi TIME SALVAGED (OTS) UIO OF SUPERIOR MASTeR DIR
MOOIF1CA TlON PSEUDO-CLOCK
os UNUSED
*
*
~
____________________________C_H_ec~~
____ '_NO_T __~
__ O_I ______________________________~1~.
UfO OF PARENT CIR •
DIRECTORY CONTROL DATA BASES DIRECTORY HEADER
B THE DIRECTORY HEADER IS A DISK RESIDENT DATA BASE CONTAINED AT THE BEGINNING OF A DIRECTORY SEGMENT
n ONE DIRECTORY HEADER PER DIRECTORY SEGMENT
B THE D~REC.TO~Y .. HEADER CONT~INS SELF DESCRIPTIVE INFORMATION SUCH AS:
4 ' , . . . . 1;. :-tr, .~. t • .. . : _ ' : " . i " ... , ... : . , .' : .. :~".:. " ", ' . . . ' f, • . ';[/ . • ~' .. '
... ':'.'
o
• • , . . . > '! '. -",.p ... , . - ~. . : '.~. ~ .',. ~.' • .; •
• ~, ,r', . . . ,.\; ••• ~,'., .'.I,,#-.~~ :,. .. • ... 1". \-. -,; ~:'._ /~,~··t~.· , .
THE' PROCESS 'ID OF THE LAST PROCESS SEGMENT'S CONTENTS
D THE DIRECTORY'S OlD, CLASSIFICATION
LVID, PVID,
~ _ .
01-TO MODIFY THE DIRECTORY
VTOC INDEX, AND AIM
o RELATIVE POINTERS TO THE BEGINNING AND END OF THE ENTRY LIST, PERSON ID LIST, PROJECT_ID ~IST; AND THE HASH TABLE
HIERARCHY DEPTH OF THE DIRECTORY SEGMENT
n UID OF THE MASTER DIRECTORY AND THE PARENT DIRECTORY
o SON'S LVID - THE ID"OF THE LV ON WHICH INFERIOR NON-DIRECTORY SEGMENTS RESIDE (AND WILL RESIDE)
B THE DIRECTORY HEADER IS ACCESSED AT THE BEGINNING OF DIRECTORY QUERY AND UPDATE OPERATIONS
Not To Be Reproduced 5-10 F8QA
o
DIRECTORY CONTROL.~ BASES DIRECTORY ENTRIES ENTRY'S UNIQUE IDENTIFIER IUID,
DATE nMe £NTRV MODIFIED (DTEM)
NUMBER OF NAMES
ACC!SS ISCLAnON MeCHANISM (AIM) CLASS .
Rm XR(31 AC1. ENTRY COUNT
ACI. START R _PTA
Be AUTHOR"S PERSON _10 R _PTA
ac AUTHOR"S TAG BIT COUNT IIF OIR. ;. 0 IMPUES MSFl SONS" IHON-OIR'S) LOGICAL VOLUME 10 (LVIO)
CHECKSUM FROM om
UIO OF PARENT DIRECTORY (WORDS)
o LINK"S UNIQUE IDENTIFIER (UID) INEYER YISIBLE TO USERS) DATE TIME ENTRY MODIFIED (DTEMI
NUMBER OF NAMES NAME LIST END R_PTA
.AUTHOR"STAG., '
IWORDS)
1. wORDS CONTAINING PRIMARY NAME
Q WORDS CONTAINING THE ABSOLUTE PATHNAME OF THE LINK"S TARGET
UIO CHECKSUM
DIRECTORY CONTROL DATA BASES DlRECTO,RY ENTRIES
B THE DIRECTORY ENTRY IS A DISK RESIDENT (RLV) DATA BASE CONTAINED WITHIN A DIRECTORY SEGMENT
D ONE DIRECTORY ENTRY (IN THE DIRECTORY SEGMENT) FOR EACH IMMEDIATELY INFERIOR ENTRY IN THE HIERARCHY
'e'
'EACH n'iREcTORY'ENTRY' I'S' A" "DATA STRUCTtiRE DESCRIB'INC; THE ATTRIBUTES" ,;' ,OF· A· SEGMENT, DIRECTO~Y, OR -LINK, . . ....
~ DIRECTORY ENTRIES COME IN TWO FLAVORS:
B LINK ENTRY, (38 OR 72 WORDS) CONTAINING:
U DATE TIME MODIFIED AND DUMPED (BY THE HIERARCHY DUMPER, NOT VOLUME DUMPER)
o RELATIVE POINTERS TO THE ENTRY'S NAME LIST AND AUTHOR'S USER ID
D ABSOLUTE PATHNAME OF THE LINK'S TARGET D OID OF PARElf! DIRECTORY
Not To Be Reproduced 5-13 F80A
DIRECTORY CONTROL ~ BASES DIRECTORY ENTRIES
D BRANCH ENTRY, (38 WORDS) CONTAINING:
o DATE TIME MODIFIED AND DUMPED (BY THE HIERARCHY DUMPER, NOT VOLUME DUMPER)
D RELATIVE POINTERS TO THE ENTRY'S NAME LIST AND AUTHOR'S OSER ID
B BRANCH'S'UID, PVID, ~ND VTOC IND~X
D ,AIM CLASSIFICATION, ENTRY POINT BOUND, .RING BRACKETS, AND . RELATIVE POINTERS TO THE ACL
o BRANCH'S BIT COUNT AND BIT COUNT AUTHOR
SON'S LVID (IF A DIRECTORY) AND PARENT'S UID
D FLAGS DESCRIBING VARIOUS STATES AND PROPERTIES OF THE ENTRY SUCH AS: DIRECTORY, MASTER DIRECTORY, SECURITY OUT OF SERVICE; COpy AND SAFETY SWITCH~ ETC
Not To Be Reproduced 5-14 FBQA
DIRECTORY CONTROL COMMANDS displaY.branch
~ DISPLAY_BRANCH - DISPLAYS BRANCHES IN THE DIRECTORY HIERARCHY
I OFTEN USEFUL ON CONJUNCT ION WITH DUMP _ VTOCE
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020756 123151~42145 162164040040 040040040040 040040040040 Sibert 020762 040040040040 040040040040 040040040040 040040040040
020766 000000000000 .. 102401170050 446752147026 000000000000 ..•• B.xC •. g ...
020772 135240026001000063000000 400000000000 000000000000 ] ..•. 3 ••....•...
020776 000000000000 000770000012 021170021300 001720000532 ..••.•.•. x ••.•••
021002 172000000000 225072707470 000000000000 000000000000 z .••• : •••.••.•..
021006 033023254650 000000000000 ..•••...
Net To Se Reproduced FgOA
TOPIC VI
Volume Management
Volume Management Overview • The New Storage System .•
Volume Management Terminology.
Volume Management Data Bases
. . . Volume Labe'l'~'! :... . •. ,. ' . . ".,~ :
..
Volume Management Operations .,.Accep'tance of' Physical Volumes • Demounting of Physical Volumes • Logical Volume Management..
Volume Management Commands • . p~int_configuration_deck
Ilst volso • • e • ., • •
":;;~T"IT::av '::ah~'_
---::---J., ---.
displayyvte •
Volume Management .Meters disk meters.
VOLUME MANAGEMENT OVERVIEW
It FUNCTION
i VOLuME MANAGEMENT IS RESPONSIBLE FOR THE MANAGEMENT OF PHYSICAL AND LOGICAL VOLUMES
D ITS TASKS INCLUDE:
1 ' ACCEPTANCE'AND' DEMOUNTING OF PHYSICAL VOLUMES
:-1 ' ' ,1-!A.I NT~I Nt NG . ~., AS.SOC I AT I, QN~, ,,;B:eTWEEN J)H~S I GAL VO~OMES,,. ,LOGI CAL . . "'VOLUMES,AND' DISK ,DRIVES' . '.' " .. '.:.,," ". .' ,""'-'-' ,
g. ENSURING THE INTEGRITY OF VOLUME CONTENTS
I MA~ING VOLUME CONTENTS ACCESSABLE TO PAGE CONTROL (PAGES) AND SEGMENT CONTROL (VTOC ENTRIES)
D VOLUME MANAGEMENT IS INVOKED ONLY BY SUBROUTINE CALLS
Noi To Be Reproduced 6-1 F8QA
VOLUME MANAGEMENT OVERVIEW
~ MAJOR DATA BASES
n PHYSICAL VOLUME TABLE (PVT) - ONE PER SYSTEM
n PHYSICAL VOLUME TABLE ENTRY (PVTE) - ONE PER DISK DRIVE :KNOWN TO THE SYSTEM
o EACH PVTE IDENTIFIES A DRIVE'S DEVICE NUMBER, SUBSYSTEM NAME, DEVICE TYPE, AND INFORMATION ABOUT THE PHYSICAL VOLUME CURRENTLY MOUNTED ..
" ~. .
U"'· USED . TO. MAP REFE:RENCES' TO" PAGES OF SEGMENTS' I:NTO AN I/O REQUEST TO THE CORRECT DISK DRIVE
o LOGICAL VOLUME TABLE (LVT) - ONE PER SYSTEM
D LOGICAL VOLUME TABLE ENTRY (LVTE) - ONE PER MOUNTED LOGICAL VOLUME .
n EACH Lv~E CONTAINS THE LOGICAL VOLL~ ID, POINTERS TO MEMBER PVTE'S, AIM CLASS LIMITS, ETC.
o USED TO DETERMINE A USER'S ACCESS TO A LOGICAL VOLUME (PRIVATE OR PUBLIC) AND TO LOCATE MEMBER PHYSICAL VOLUMES
o VOLUME HEADER - ONE PER PACK
o VOLUME LABEL (REGISTRATION AND ACCEPTANCE INFORMATION)
D VOLUME MAP (OCCUPIEDjVACANT INFORMATION FOR VOLUME CONTENTS)
Not To Be Reproduced 6-2 F8QA
VOLUME MANAGEMENT OVERVIEW
D RECORD STOCKS - ONE PER MOUNTED VOLUME
D ONLINE CACHE OF INFORMATION ABOUT USED / UNUSED RECORDS ON THE VOLtJ"ME
B THI S I NFORMA TI ON IS DERI VED FROM , THE VOLUME MAP, BUT KEPT ONLINE TO AVOID THE NECESSITY OF REFERRING TO THE VOLUME MAP ON DISK EVERY TIME A RECORD IS ALLOCATED OR FREED
8
WHEN THE CACHE BECOMES COMPLETELY EMPTY OR COMPLETELY FULL, .. ,IT ,MOST BEUPDA:TED FROM/TO DISK ~ A PROTOCOL ENSURES THAT THECOpy ON DISK' IS ALWAYS CONSISTENT
D PROVIDED BY VOLUME MANAGEMENT, BUT USED BY PAGE CONTROL
n VTOCE STOCKS'- ONE PER VOLUME
&
SIMILAR TO RECORD STOCKS, BL~ ¥AINTAINS INFO~vATION ABOUT USED / UNUSED VTOC ENTRIES ON THE VOLUMEo PROVIDED BY VOLUME MANAGE~NT, BUT USED BY SEGMENT CONTROL
o PHYSICAL VOLUME HOLD TABLE (PVHT) - ONE PER SYSTEM
. RECORDS THE COMMENCEMENT OF COMPOUND I/O OPERATIONS UPON A PHYSICAL VOLUME
o THIS INFORMAT~ON PREVENTS A VOLUME FROM BEING DEMOUNTED WHILE SUCH AN OPERATION IS IN PROGRESS
Not To Be Reproduced 6-3 F8QA
0'\
PHYSICAL VOLUME (PV):
LOGICAL VOLUME (LV):
VOLUME HEADER:
VOLUME TABLE OF CONTENTS (VTOCI:
PAQING REGION: VOLUMES GIVEN A S,NGlE LOGICAL IDENTITY CONTAINS THE LABEL, VOLUME MAP, VTOC THAN PAGES OF STORAGE SYSTEM SEGMENTS