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+--------+-------------------------+-------------------------+--------+--------+
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|00000480| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 0a 54 69 74 6c 65 3a |--------|-.Title:|
|00000490| 20 20 20 20 20 44 65 73 | 69 67 6e 20 67 6f 61 6c |     Des|ign goal|
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|00000500| 6c 65 20 6f 6e 20 42 20 | 54 72 65 65 73 20 61 6e |le on B |Trees an|
|00000510| 64 20 42 2b 20 54 72 65 | 65 73 29 0a 41 75 74 68 |d B+ Tre|es).Auth|
|00000520| 6f 72 3a 20 20 20 20 44 | 75 6e 63 61 6e 2c 20 52 |or:    D|uncan, R|
|00000530| 6f 79 2e 0a 20 0a 53 75 | 6d 6d 61 72 79 3a 20 20 |oy.. .Su|mmary:  |
|00000540| 20 54 68 65 20 48 69 67 | 68 20 50 65 72 66 6f 72 | The Hig|h Perfor|
|00000550| 6d 61 6e 63 65 20 46 69 | 6c 65 20 53 79 73 74 65 |mance Fi|le Syste|
|00000560| 6d 20 28 48 50 46 53 29 | 20 65 6e 68 61 6e 63 65 |m (HPFS)| enhance|
|00000570| 6d 65 6e 74 20 74 6f 20 | 4f 53 2f 32 20 56 65 72 |ment to |OS/2 Ver|
|00000580| 73 69 6f 6e 0a 20 20 20 | 20 20 20 20 20 20 20 20 |sion.   |        |
|00000590| 31 2e 32 20 73 6f 6c 76 | 65 73 20 61 6c 6c 20 74 |1.2 solv|es all t|
|000005a0| 68 65 20 70 72 6f 62 6c | 65 6d 73 20 6f 66 20 74 |he probl|ems of t|
|000005b0| 68 65 20 46 69 6c 65 20 | 41 6c 6c 6f 63 61 74 69 |he File |Allocati|
|000005c0| 6f 6e 20 54 61 62 6c 65 | 20 28 46 41 54 29 20 66 |on Table| (FAT) f|
|000005d0| 69 6c 65 0a 20 20 20 20 | 20 20 20 20 20 20 20 73 |ile.    |       s|
|000005e0| 79 73 74 65 6d 20 61 6e | 64 20 69 73 20 64 65 73 |ystem an|d is des|
|000005f0| 69 67 6e 65 64 20 74 6f | 20 6d 65 65 74 20 74 68 |igned to| meet th|
|00000600| 65 20 64 65 6d 61 6e 64 | 73 20 65 78 70 65 63 74 |e demand|s expect|
|00000610| 65 64 20 69 6e 74 6f 20 | 74 68 65 20 6e 65 78 74 |ed into |the next|
|00000620| 20 66 65 77 0a 20 20 20 | 20 20 20 20 20 20 20 20 | few.   |        |
|00000630| 64 65 63 61 64 65 73 2e | 20 20 48 50 46 53 20 6e |decades.|  HPFS n|
|00000640| 6f 74 20 6f 6e 6c 79 20 | 73 65 72 76 65 73 20 61 |ot only |serves a|
|00000650| 73 20 61 20 77 61 79 20 | 74 6f 20 6f 72 67 61 6e |s a way |to organ|
|00000660| 69 7a 65 20 64 61 74 61 | 20 6f 6e 20 72 61 6e 64 |ize data| on rand|
|00000670| 6f 6d 0a 20 20 20 20 20 | 20 20 20 20 20 20 61 63 |om.     |      ac|
|00000680| 63 65 73 73 20 62 6c 6f | 63 6b 20 73 74 6f 72 61 |cess blo|ck stora|
|00000690| 67 65 20 64 65 76 69 63 | 65 73 2c 20 62 75 74 20 |ge devic|es, but |
|000006a0| 69 73 20 61 6c 73 6f 20 | 61 20 73 6f 66 74 77 61 |is also |a softwa|
|000006b0| 72 65 20 6d 6f 64 75 6c | 65 20 74 68 61 74 0a 20 |re modul|e that. |
|000006c0| 20 20 20 20 20 20 20 20 | 20 20 74 72 61 6e 73 6c |        |  transl|
|000006d0| 61 74 65 73 20 66 69 6c | 65 2d 6f 72 69 65 6e 74 |ates fil|e-orient|
|000006e0| 65 64 20 72 65 71 75 65 | 73 74 73 20 66 72 6f 6d |ed reque|sts from|
|000006f0| 20 61 70 70 6c 69 63 61 | 74 69 6f 6e 73 20 70 72 | applica|tions pr|
|00000700| 6f 67 72 61 6d 73 20 74 | 6f 20 64 65 76 69 63 65 |ograms t|o device|
|00000710| 0a 20 20 20 20 20 20 20 | 20 20 20 20 64 72 69 76 |.       |    driv|
|00000720| 65 72 73 2e 20 20 48 50 | 46 53 20 69 73 20 61 6c |ers.  HP|FS is al|
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|00000750| 66 69 6c 65 20 73 79 73 | 74 65 6d 20 77 68 69 63 |file sys|tem whic|
|00000760| 68 0a 20 20 20 20 20 20 | 20 20 20 20 20 6d 61 6b |h.      |     mak|
|00000770| 65 73 20 69 74 20 70 6f | 73 73 69 62 6c 65 20 74 |es it po|ssible t|
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|00000790| 20 69 6e 63 6f 6d 70 61 | 74 69 62 6c 65 20 76 6f | incompa|tible vo|
|000007a0| 6c 75 6d 65 20 73 74 72 | 75 63 74 75 72 65 73 0a |lume str|uctures.|
|000007b0| 20 20 20 20 20 20 20 20 | 20 20 20 6f 6e 20 74 68 |        |   on th|
|000007c0| 65 20 73 61 6d 65 20 4f | 53 2f 32 20 73 79 73 74 |e same O|S/2 syst|
|000007d0| 65 6d 20 73 69 6d 75 6c | 74 61 6e 65 6f 75 73 6c |em simul|taneousl|
|000007e0| 79 2e 20 20 45 78 63 65 | 6c 6c 65 6e 74 20 74 68 |y.  Exce|llent th|
|000007f0| 72 6f 75 67 68 70 75 74 | 20 69 73 0a 20 20 20 20 |roughput| is.    |
|00000800| 20 20 20 20 20 20 20 61 | 63 68 69 65 76 65 64 20 |       a|chieved |
|00000810| 62 79 20 74 68 65 20 75 | 73 65 20 6f 66 20 61 64 |by the u|se of ad|
|00000820| 76 61 6e 63 65 64 20 64 | 61 74 61 20 73 74 72 75 |vanced d|ata stru|
|00000830| 63 74 75 72 65 73 20 73 | 75 63 68 20 61 73 20 69 |ctures s|uch as i|
|00000840| 6e 74 65 6c 6c 69 67 65 | 6e 74 0a 20 20 20 20 20 |ntellige|nt.     |
|00000850| 20 20 20 20 20 20 63 61 | 63 68 69 6e 67 2c 20 72 |      ca|ching, r|
|00000860| 65 61 64 2d 61 68 65 61 | 64 20 61 6e 64 20 77 72 |ead-ahea|d and wr|
|00000870| 69 74 65 2d 62 65 68 69 | 6e 64 2e 20 20 44 69 73 |ite-behi|nd.  Dis|
|00000880| 6b 20 73 70 61 63 65 20 | 69 73 20 6d 61 6e 61 67 |k space |is manag|
|00000890| 65 64 20 6d 6f 72 65 0a | 20 20 20 20 20 20 20 20 |ed more.|        |
|000008a0| 20 20 20 65 63 6f 6e 6f | 6d 69 63 61 6c 6c 79 20 |   econo|mically |
|000008b0| 62 79 20 74 68 65 20 75 | 73 65 20 6f 66 20 73 65 |by the u|se of se|
|000008c0| 63 74 6f 72 69 6e 67 2e | 20 20 48 50 46 53 20 61 |ctoring.|  HPFS a|
|000008d0| 6c 73 6f 20 69 6e 63 6c | 75 64 65 73 20 67 72 65 |lso incl|udes gre|
|000008e0| 61 74 6c 79 0a 20 20 20 | 20 20 20 20 20 20 20 20 |atly.   |        |
|000008f0| 69 6d 70 72 6f 76 65 64 | 20 66 61 75 6c 74 20 74 |improved| fault t|
|00000900| 6f 6c 65 72 61 6e 63 65 | 2e 20 20 41 70 70 6c 69 |olerance|.  Appli|
|00000910| 63 61 74 69 6f 6e 73 20 | 70 72 6f 67 72 61 6d 73 |cations |programs|
|00000920| 20 6e 65 65 64 20 6f 6e | 6c 79 20 73 69 6d 70 6c | need on|ly simpl|
|00000930| 65 0a 20 20 20 20 20 20 | 20 20 20 20 20 6d 6f 64 |e.      |     mod|
|00000940| 69 66 69 63 61 74 69 6f | 6e 73 20 74 6f 20 6d 61 |ificatio|ns to ma|
|00000950| 6b 65 20 75 73 65 20 6f | 66 20 65 78 74 65 6e 64 |ke use o|f extend|
|00000960| 65 64 20 61 74 74 72 69 | 62 75 74 65 73 20 61 6e |ed attri|butes an|
|00000970| 64 20 6c 6f 6e 67 20 66 | 69 6c 65 6e 61 6d 65 73 |d long f|ilenames|
|00000980| 2e 0a 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |..------|--------|
|00000990| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000009a0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000009b0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|000009c0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 0a |--------|-------.|
|000009d0| 44 65 73 63 72 69 70 74 | 6f 72 73 2e 2e 0a 50 72 |Descript|ors...Pr|
|000009e0| 6f 64 75 63 74 3a 20 20 | 20 4f 53 2d 32 20 45 78 |oduct:  | OS-2 Ex|
|000009f0| 74 65 6e 64 65 64 20 45 | 64 69 74 69 6f 6e 20 31 |tended E|dition 1|
|00000a00| 2e 32 20 28 4f 70 65 72 | 61 74 69 6e 67 20 73 79 |.2 (Oper|ating sy|
|00000a10| 73 74 65 6d 29 20 28 70 | 72 6f 64 75 63 74 20 65 |stem) (p|roduct e|
|00000a20| 6e 68 61 6e 63 65 6d 65 | 6e 74 29 2e 0a 54 6f 70 |nhanceme|nt)..Top|
|00000a30| 69 63 3a 20 20 20 20 20 | 4f 53 2d 32 0a 20 20 20 |ic:     |OS-2.   |
|00000a40| 20 20 20 20 20 20 20 20 | 46 69 6c 65 20 4d 61 6e |        |File Man|
|00000a50| 61 67 65 6d 65 6e 74 0a | 20 20 20 20 20 20 20 20 |agement.|        |
|00000a60| 20 20 20 45 6e 68 61 6e | 63 65 6d 65 6e 74 73 0a |   Enhan|cements.|
|00000a70| 20 20 20 20 20 20 20 20 | 20 20 20 44 61 74 61 20 |        |   Data |
|00000a80| 53 74 72 75 63 74 75 72 | 65 73 0a 20 20 20 20 20 |Structur|es.     |
|00000a90| 20 20 20 20 20 20 44 69 | 73 6b 20 53 70 61 63 65 |      Di|sk Space|
|00000aa0| 20 41 6c 6c 6f 63 61 74 | 69 6f 6e 0a 20 20 20 20 | Allocat|ion.    |
|00000ab0| 20 20 20 20 20 20 20 53 | 65 63 74 6f 72 69 6e 67 |       S|ectoring|
|00000ac0| 2e 0a 46 65 61 74 75 72 | 65 3a 20 20 20 69 6c 6c |..Featur|e:   ill|
|00000ad0| 75 73 74 72 61 74 69 6f | 6e 0a 20 20 20 20 20 20 |ustratio|n.      |
|00000ae0| 20 20 20 20 20 74 61 62 | 6c 65 0a 20 20 20 20 20 |     tab|le.     |
|00000af0| 20 20 20 20 20 20 63 68 | 61 72 74 2e 0a 43 61 70 |      ch|art..Cap|
|00000b00| 74 69 6f 6e 3a 20 20 20 | 28 43 6f 6d 70 61 72 69 |tion:   |(Compari|
|00000b10| 73 6f 6e 20 6f 66 20 46 | 41 54 20 61 6e 64 20 48 |son of F|AT and H|
|00000b20| 69 67 68 20 50 65 72 66 | 6f 72 6d 61 6e 63 65 20 |igh Perf|ormance |
|00000b30| 46 69 6c 65 20 53 79 73 | 74 65 6d 2e 29 0a 20 20 |File Sys|tem.).  |
|00000b40| 20 20 20 20 20 20 20 20 | 20 28 4f 76 65 72 61 6c |        | (Overal|
|00000b50| 6c 20 73 74 72 75 63 74 | 75 72 65 20 6f 66 20 61 |l struct|ure of a|
|00000b60| 6e 20 48 50 46 53 20 76 | 6f 6c 75 6d 65 2e 29 0a |n HPFS v|olume.).|
|00000b70| 20 20 20 20 20 20 20 20 | 20 20 20 28 4f 76 65 72 |        |   (Over|
|00000b80| 61 6c 6c 20 73 74 72 75 | 63 74 75 72 65 20 6f 66 |all stru|cture of|
|00000b90| 20 61 6e 20 46 6e 6f 64 | 65 2e 29 0a 20 0a 52 65 | an Fnod|e.). .Re|
|00000ba0| 63 6f 72 64 23 3a 20 20 | 20 30 37 20 35 38 35 20 |cord#:  | 07 585 |
|00000bb0| 34 35 34 2e 0a 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |454..---|--------|
|00000bc0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00000bd0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00000be0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00000bf0| 2d 2d 2d 2d 2d 2d 2d 2d | 2d 2d 2d 2d 2d 2d 2d 2d |--------|--------|
|00000c00| 2d 2d 0a 46 75 6c 6c 20 | 54 65 78 74 3a 0a 20 0a |--.Full |Text:. .|
|00000c10| 5c 65 6e 64 7b 76 65 72 | 62 61 74 69 6d 7d 0a 5c |\end{ver|batim}.\|
|00000c20| 6e 6f 69 6e 64 65 6e 74 | 0a 7b 5c 73 66 20 54 48 |noindent|.{\sf TH|
|00000c30| 45 20 48 50 46 53 20 49 | 53 20 41 20 57 41 59 20 |E HPFS I|S A WAY |
|00000c40| 4f 46 20 4f 52 47 41 4e | 49 5a 49 4e 47 20 44 41 |OF ORGAN|IZING DA|
|00000c50| 54 41 20 4f 4e 20 41 20 | 52 41 4e 44 4f 4d 20 41 |TA ON A |RANDOM A|
|00000c60| 43 43 45 53 53 20 42 4c | 4f 43 4b 20 53 54 4f 52 |CCESS BL|OCK STOR|
|00000c70| 41 47 45 0a 44 45 56 49 | 43 45 2e 0a 49 54 20 49 |AGE.DEVI|CE..IT I|
|00000c80| 53 20 41 4c 53 4f 20 41 | 20 53 4f 46 54 57 41 52 |S ALSO A| SOFTWAR|
|00000c90| 45 20 4d 4f 44 55 4c 45 | 20 54 48 41 54 20 54 52 |E MODULE| THAT TR|
|00000ca0| 41 4e 53 4c 41 54 45 53 | 20 46 49 4c 45 2d 4f 52 |ANSLATES| FILE-OR|
|00000cb0| 49 45 4e 54 45 44 20 52 | 45 51 55 45 53 54 53 20 |IENTED R|EQUESTS |
|00000cc0| 46 52 4f 4d 20 41 4e 0a | 41 50 50 4c 49 43 41 54 |FROM AN.|APPLICAT|
|00000cd0| 49 4f 4e 20 50 52 4f 47 | 52 41 4d 20 49 4e 54 4f |ION PROG|RAM INTO|
|00000ce0| 20 4d 4f 52 45 20 50 52 | 49 4d 49 54 49 56 45 20 | MORE PR|IMITIVE |
|00000cf0| 52 45 51 55 45 53 54 53 | 20 54 48 41 54 20 41 20 |REQUESTS| THAT A |
|00000d00| 44 45 56 49 43 45 20 44 | 52 49 56 45 52 20 43 41 |DEVICE D|RIVER CA|
|00000d10| 4e 0a 55 4e 44 45 52 53 | 54 41 4e 44 2e 7d 0a 20 |N.UNDERS|TAND.}. |
|00000d20| 0a 54 68 65 20 48 69 67 | 68 20 50 65 72 66 6f 72 |.The Hig|h Perfor|
|00000d30| 6d 61 6e 63 65 20 46 69 | 6c 65 20 53 79 73 74 65 |mance Fi|le Syste|
|00000d40| 6d 20 28 68 65 72 65 61 | 66 74 65 72 20 48 50 46 |m (herea|fter HPF|
|00000d50| 53 29 2c 20 77 68 69 63 | 68 20 69 73 20 6d 61 6b |S), whic|h is mak|
|00000d60| 69 6e 67 20 69 74 73 20 | 66 69 72 73 74 0a 61 70 |ing its |first.ap|
|00000d70| 70 65 61 72 61 6e 63 65 | 20 69 6e 20 74 68 65 20 |pearance| in the |
|00000d80| 4f 53 2f 32 20 6f 70 65 | 72 61 74 69 6e 67 20 73 |OS/2 ope|rating s|
|00000d90| 79 73 74 65 6d 20 56 65 | 72 73 69 6f 6e 20 31 2e |ystem Ve|rsion 1.|
|00000da0| 32 2c 20 68 61 64 20 69 | 74 73 20 67 65 6e 65 73 |2, had i|ts genes|
|00000db0| 69 73 20 69 6e 20 74 68 | 65 0a 6e 65 74 77 6f 72 |is in th|e.networ|
|00000dc0| 6b 20 64 69 76 69 73 69 | 6f 6e 20 6f 66 20 4d 69 |k divisi|on of Mi|
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+--------+-------------------------+-------------------------+--------+--------+