%!PS-Adobe-3.0 %%Creator: Windows PSCRIPT %%Title: Microsoft Word - DETERM.NIS %%BoundingBox: 18 19 593 774 %%DocumentNeededResources: (atend) %%DocumentSuppliedResources: (atend) %%Pages: (atend) %%BeginResource: procset Win35Dict 3 1 /Win35Dict 290 dict def Win35Dict begin/bd{bind def}bind def/in{72 mul}bd/ed{exch def}bd/ld{load def}bd/tr/translate ld/gs/gsave ld/gr /grestore ld/M/moveto ld/L/lineto ld/rmt/rmoveto ld/rlt/rlineto ld /rct/rcurveto ld/st/stroke ld/n/newpath ld/sm/setmatrix ld/cm/currentmatrix ld/cp/closepath ld/ARC/arcn ld/TR{65536 div}bd/lj/setlinejoin ld/lc /setlinecap ld/ml/setmiterlimit ld/sl/setlinewidth ld/scignore false def/sc{scignore{pop pop pop}{0 index 2 index eq 2 index 4 index eq and{pop pop 255 div setgray}{3{255 div 3 1 roll}repeat setrgbcolor}ifelse}ifelse}bd /FC{bR bG bB sc}bd/fC{/bB ed/bG ed/bR ed}bd/HC{hR hG hB sc}bd/hC{ /hB ed/hG ed/hR ed}bd/PC{pR pG pB sc}bd/pC{/pB ed/pG ed/pR ed}bd/sM matrix def/PenW 1 def/iPen 5 def/mxF matrix def/mxE matrix 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(arise ) 100 SB 1065 728 37 (if ) 46 SB 1111 728 52 (the) 52 SB 150 778 202 (buffer used ) 203 SB 353 778 44 (to ) 45 SB 398 778 86 (hold ) 87 SB 485 778 63 (the ) 64 SB 549 778 93 (copy ) 94 SB 643 778 46 (of ) 47 SB 690 778 63 (the ) 64 SB 754 778 154 (message ) 155 SB 909 778 152 (contains ) 153 SB 1062 778 101 (unini-) 101 SB 150 828 137 (tialized ) 147 SB 297 828 116 (fields. ) 126 SB 423 828 11 ( ) 21 SB 444 828 39 (If ) 49 SB 493 828 63 (the ) 73 SB 566 828 173 (compiler, ) 184 SB 750 828 46 (or ) 57 SB 807 828 63 (the ) 74 SB 881 828 130 (TWOS ) 141 SB 1022 828 141 (memory) 141 SB 150 878 228 (management ) 253 SB 403 878 139 (system, ) 164 SB 567 878 121 (allows ) 146 SB 713 878 98 (these ) 124 SB 837 878 105 (fields ) 131 SB 968 878 44 (to ) 70 SB 1038 878 125 (contain) 125 SB 150 928 157 (different ) 171 SB 321 928 224 (uninitialized ) 238 SB 559 928 130 (values, ) 144 SB 703 928 84 (then ) 98 SB 801 928 200 (supposedly ) 215 SB 1016 928 147 (identical) 147 SB 150 978 170 (messages ) 180 SB 330 978 105 (could ) 116 SB 446 978 146 (actually ) 157 SB 603 978 136 (contain ) 147 SB 750 978 157 (different ) 168 SB 918 978 152 (contents ) 163 SB 1081 978 82 (from) 82 SB 150 1028 67 (run ) 68 SB 218 1028 44 (to ) 45 SB 263 1028 78 (run, ) 79 SB 342 1028 159 (resulting ) 161 SB 503 1028 44 (in ) 46 SB 549 1028 157 (different ) 159 SB 708 1028 170 (orderings ) 172 SB 880 1028 46 (of ) 48 SB 928 1028 63 (the ) 65 SB 993 1028 170 (messages.) 170 SB 150 1078 130 (TWOS ) 146 SB 296 1078 116 (solves ) 132 SB 428 1078 72 (this ) 88 SB 516 1078 152 (problem ) 169 SB 685 1078 53 (by ) 70 SB 755 1078 156 (ensuring ) 173 SB 928 1078 75 (that ) 92 SB 1020 1078 143 (message) 143 SB 150 1128 130 (buffers ) 134 SB 284 1128 63 (are ) 67 SB 351 1128 128 (always ) 132 SB 483 1128 134 (cleared ) 138 SB 621 1128 119 (before ) 124 SB 745 1128 105 (being ) 110 SB 855 1128 105 (given ) 110 SB 965 1128 44 (to ) 49 SB 1014 1128 63 (the ) 68 SB 1082 1128 81 (user,) 81 SB 150 1178 72 (and ) 82 SB 232 1178 53 (by ) 63 SB 295 1178 91 (ensur) 91 SB 386 1178 65 (ing ) 75 SB 461 1178 75 (that ) 86 SB 547 1178 63 (the ) 74 SB 621 1178 162 (compiler ) 173 SB 794 1178 88 (does ) 99 SB 893 1178 65 (not ) 76 SB 969 1178 122 (permit ) 133 SB 1102 1178 61 (any) 61 SB 150 1228 149 (portions ) 157 SB 307 1228 46 (of ) 54 SB 361 1228 30 (a ) 38 SB 399 1228 159 (structure ) 167 SB 566 1228 44 (to ) 53 SB 619 1228 136 (contain ) 145 SB 764 1228 235 (uninitialized, ) 244 SB 1008 1228 155 (unzeroed) 155 SB 150 1278 105 (fields.) 105 SB 150 1378 130 (TWOS ) 141 SB 291 1378 93 (must ) 104 SB 395 1378 79 (also ) 90 SB 485 1378 140 (provide ) 151 SB 636 1378 63 (the ) 74 SB 710 1378 175 (necessary ) 186 SB 896 1378 192 (guarantees ) 203 SB 1099 1378 64 (that) 64 SB 150 1428 59 (roll) 59 SB 209 1428 107 (backs ) 109 SB 318 1428 77 (will ) 79 SB 397 1428 105 (occur ) 107 SB 504 1428 154 (properly ) 156 SB 660 1428 175 (whenever ) 177 SB 837 1428 186 (necessary, ) 188 SB 1025 1428 138 (undoing) 138 SB 150 1478 164 (precisely ) 170 SB 320 1478 75 (that ) 81 SB 401 1478 97 (work ) 103 SB 504 1478 75 (that ) 81 SB 585 1478 76 (was ) 82 SB 667 1478 93 (done ) 99 SB 766 1478 44 (in ) 50 SB 816 1478 104 (error. ) 110 SB 926 1478 11 ( ) 18 SB 944 1478 130 (TWOS ) 137 SB 1081 1478 82 (must) 82 SB 150 1528 126 (further ) 141 SB 291 1528 116 (assure ) 131 SB 422 1528 75 (that ) 90 SB 512 1528 63 (the ) 78 SB 590 1528 97 (work ) 112 SB 702 1528 77 (will ) 92 SB 794 1528 51 (be ) 66 SB 860 1528 126 (redone ) 141 SB 1001 1528 162 (correctly.) 162 SB 150 1578 176 (However, ) 177 SB 327 1578 98 (these ) 99 SB 426 1578 192 (guarantees ) 193 SB 619 1578 63 (are ) 65 SB 684 1578 175 (necessary ) 177 SB 861 1578 60 (for ) 62 SB 923 1578 137 (reasons ) 139 SB 1062 1578 101 (above) 101 SB 150 1628 893 (and beyond determinism. Without such guarantees, ) 894 SB 1044 1628 119 (TWOS) 119 SB 150 1678 116 (would ) 123 SB 273 1678 105 (never ) 112 SB 385 1678 51 (be ) 58 SB 443 1678 82 (able ) 89 SB 532 1678 44 (to ) 51 SB 583 1678 103 (make ) 110 SB 693 1678 72 (any ) 79 SB 772 1678 86 (assur) 86 SB 858 1678 105 (ances ) 113 SB 971 1678 192 (whatsoever) 192 SB 150 1728 75 (that ) 81 SB 231 1728 35 (it ) 41 SB 272 1728 76 (was ) 82 SB 354 1728 171 (operating ) 177 SB 531 1728 44 (in ) 50 SB 581 1728 30 (a ) 36 SB 617 1728 129 (correct ) 135 SB 752 1728 149 (manner. ) 155 SB 907 1728 11 ( ) 17 SB 924 1728 123 (Proper ) 130 SB 1054 1728 67 (use ) 74 SB 1128 1728 35 (of) 35 SB 150 1778 161 (rollback, ) 163 SB 313 1778 154 (message ) 156 SB 469 1778 228 (cancellation, ) 230 SB 699 1778 72 (and ) 74 SB 773 1778 223 (re-execution ) 225 SB 998 1778 39 (is ) 42 SB 1040 1778 87 (vital ) 90 SB 1130 1778 33 (to) 33 SB 150 1828 852 (TWOS, and has been implemented very carefully.) 852 SB 150 1928 81 (One ) 87 SB 237 1928 126 (further ) 132 SB 369 1928 152 (problem ) 158 SB 527 1928 39 (is ) 45 SB 572 1928 175 (providing ) 181 SB 753 1928 233 (deterministic ) 240 SB 993 1928 121 (results ) 128 SB 1121 1928 42 (on) 42 SB 150 1978 106 (hetero) 106 SB 256 1978 149 (geneous ) 175 SB 431 1978 179 (hardware. ) 205 SB 636 1978 11 ( ) 37 SB 673 1978 46 (In ) 73 SB 746 1978 63 (the ) 90 SB 836 1978 138 (simpler ) 165 SB 1001 1978 95 (case, ) 122 SB 1123 1978 40 (an) 40 SB 150 2028 651 (application run on two different types ) 652 SB 802 2028 46 (of ) 47 SB 849 2028 155 (machine ) 156 SB 1005 2028 84 (may ) 85 SB 1090 2028 73 (give) 73 SB 150 2078 179 (determinis) 179 SB 329 2078 54 (tic ) 74 SB 403 2078 146 (answers ) 166 SB 569 2078 53 (on ) 73 SB 642 2078 89 (each ) 109 SB 751 2078 84 (type ) 104 SB 855 2078 46 (of ) 67 SB 922 2078 166 (machine, ) 187 SB 1109 2078 54 (but) 54 SB 150 2128 157 (different ) 185 SB 335 2128 146 (answers ) 174 SB 509 2128 152 (between ) 180 SB 689 2128 63 (the ) 91 SB 780 2128 139 (classes. ) 167 SB 947 2128 11 ( ) 39 SB 986 2128 113 (Issues ) 142 SB 1128 2128 35 (of) 35 SB 150 2178 251 (representation ) 253 SB 403 2178 46 (of ) 48 SB 451 2178 135 (various ) 137 SB 588 2178 82 (data ) 85 SB 673 2178 100 (types ) 103 SB 776 2178 102 (\(such ) 105 SB 881 2178 46 (as ) 49 SB 930 2178 143 (floating ) 146 SB 1076 2178 87 (point) 87 SB 150 2228 170 (numbers\) ) 175 SB 325 2228 72 (and ) 77 SB 402 2228 63 (the ) 68 SB 470 2228 100 (order ) 105 SB 575 2228 46 (of ) 51 SB 626 2228 100 (bytes ) 105 SB 731 2228 119 (within ) 125 SB 856 2228 30 (a ) 36 SB 892 2228 97 (word ) 103 SB 995 2228 70 (can ) 76 SB 1071 2228 92 (make) 92 SB 150 2278 175 (providing ) 194 SB 344 2278 63 (the ) 83 SB 427 2278 98 (same ) 118 SB 545 2278 130 (answer ) 150 SB 695 2278 116 (across ) 136 SB 831 2278 157 (different ) 177 SB 1008 2278 100 (types ) 120 SB 1128 2278 35 (of) 35 SB 150 2328 405 (machines very difficult.) 405 SB 150 2428 77 (The ) 82 SB 232 2428 152 (problem ) 158 SB 390 2428 39 (is ) 45 SB 435 2428 91 (even ) 97 SB 532 2428 111 (worse ) 117 SB 649 2428 37 (if ) 43 SB 692 2428 63 (the ) 69 SB 761 2428 200 (application ) 206 SB 967 2428 39 (is ) 45 SB 1012 2428 67 (run ) 73 SB 1085 2428 53 (on ) 59 SB 1144 2428 19 (a) 19 SB 150 2478 106 (hetero) 106 SB 256 2478 149 (geneous ) 156 SB 412 2478 160 (network. ) 167 SB 579 2478 11 ( ) 18 SB 597 2478 46 (In ) 53 SB 650 2478 72 (this ) 79 SB 729 2478 95 (case, ) 102 SB 831 2478 175 (providing ) 182 SB 1013 2478 91 (even ) 98 SB 1111 2478 52 (the) 52 SB 150 2528 379 (same results from run ) 380 SB 530 2528 44 (to ) 45 SB 575 2528 67 (run ) 68 SB 643 2528 53 (on ) 54 SB 697 2528 63 (the ) 64 SB 761 2528 98 (same ) 99 SB 860 2528 58 (set ) 59 SB 919 2528 46 (of ) 47 SB 966 2528 168 (hardware ) 169 SB 1135 2528 28 (is) 28 SB 150 2578 963 (difficult unless all objects reside on the same processors ) 964 SB 1114 2578 49 (for) 49 SB 150 2628 148 (all runs. ) 149 SB 299 2628 11 ( ) 12 SB 311 2628 105 (Since ) 106 SB 417 2628 106 (hetero) 106 SB 523 2628 136 (geneity ) 137 SB 660 2628 39 (is ) 40 SB 700 2628 65 (not ) 66 SB 766 2628 63 (the ) 64 SB 830 2628 102 (focus ) 103 SB 933 2628 46 (of ) 47 SB 980 2628 63 (the ) 64 SB 1044 2628 119 (TWOS) 119 SB 150 2678 140 (project, ) 141 SB 291 2678 90 (little ) 91 SB 382 2678 67 (has ) 68 SB 450 2678 91 (been ) 92 SB 542 2678 93 (done ) 94 SB 636 2678 44 (to ) 45 SB 681 2678 82 (deal ) 83 SB 764 2678 86 (with ) 87 SB 851 2678 72 (this ) 73 SB 924 2678 106 (issue. ) 107 SB 1031 2678 11 ( ) 13 SB 1044 2678 119 (TWOS) 119 SB 150 2728 833 (runs are always done on homogeneous hardware.) 833 SB 32 0 0 42 42 1 0 0 38 /Times-Roman /font32 ANSIFont font 411 2828 491 (Determinism and Debugging) 491 SB 32 0 0 42 42 0 0 0 38 /Times-Roman /font32 ANSIFont font 1238 228 105 (Since ) 108 SB 1346 228 130 (TWOS ) 133 SB 1479 228 93 (must ) 96 SB 1575 228 51 (be ) 54 SB 1629 228 197 (guaranteed ) 201 SB 1830 228 44 (to ) 48 SB 1878 228 147 (produce ) 151 SB 2029 228 222 (deterministic) 222 SB 1238 278 121 (results ) 131 SB 1369 278 102 (when ) 112 SB 1481 278 216 (applications ) 226 SB 1707 278 170 (programs ) 181 SB 1888 278 121 (follow ) 132 SB 2020 278 127 (certain ) 138 SB 2158 278 93 (rules,) 93 SB 1238 328 897 (any non-determinism that appears in a TWOS run is ) 898 SB 2136 328 115 (caused) 115 SB 1238 378 53 (by ) 57 SB 1295 378 51 (an ) 55 SB 1350 378 93 (error ) 97 SB 1447 378 44 (in ) 48 SB 1495 378 108 (either ) 113 SB 1608 378 63 (the ) 68 SB 1676 378 200 (application ) 205 SB 1881 378 46 (or ) 51 SB 1932 378 141 (TWOS. ) 146 SB 2078 378 11 ( ) 16 SB 2094 378 100 (Once ) 105 SB 2199 378 52 (the) 52 SB 1238 428 85 (appli) 85 SB 1323 428 115 (cation ) 120 SB 1443 428 67 (has ) 73 SB 1516 428 91 (been ) 97 SB 1613 428 150 (checked ) 156 SB 1769 428 44 (to ) 50 SB 1819 428 103 (make ) 109 SB 1928 428 81 (sure ) 87 SB 2015 428 35 (it ) 41 SB 2056 428 137 (follows ) 143 SB 2199 428 52 (the) 52 SB 1238 478 798 (rules, the problem is narrowed to TWOS itself.) 798 SB 1238 578 130 (TWOS ) 152 SB 1390 578 107 (keeps ) 129 SB 1519 578 157 (statistics ) 179 SB 1698 578 75 (that ) 97 SB 1795 578 102 (assist ) 124 SB 1919 578 44 (in ) 66 SB 1985 578 167 (detecting ) 189 SB 2174 578 77 (non-) 77 SB 1238 628 151 (determin) 151 SB 1389 628 83 (ism. ) 92 SB 1481 628 11 ( ) 20 SB 1501 628 77 (The ) 87 SB 1588 628 183 (sequential ) 193 SB 1781 628 67 (run ) 77 SB 1858 628 46 (of ) 56 SB 1914 628 51 (an ) 61 SB 1975 628 73 (appl) 73 SB 2048 628 127 (ication ) 137 SB 2185 628 66 (will) 66 SB 1238 678 490 (produce a certain number of ) 491 SB 1729 678 170 (messages ) 171 SB 1900 678 79 (sent ) 80 SB 1980 678 93 (from ) 94 SB 2074 678 72 (one ) 73 SB 2147 678 104 (object) 104 SB 1238 728 44 (to ) 45 SB 1283 728 149 (another, ) 150 SB 1433 728 72 (and ) 74 SB 1507 728 30 (a ) 32 SB 1539 728 127 (certain ) 129 SB 1668 728 140 (number ) 142 SB 1810 728 46 (of ) 48 SB 1858 728 119 (events ) 121 SB 1979 728 126 (caused ) 128 SB 2107 728 53 (by ) 55 SB 2162 728 89 (those) 89 SB 1238 778 181 (messages. ) 192 SB 1430 778 11 ( ) 22 SB 1452 778 119 (\(Since ) 131 SB 1583 778 51 (an ) 63 SB 1646 778 103 (event ) 115 SB 1761 778 70 (can ) 82 SB 1843 778 51 (be ) 63 SB 1906 778 126 (caused ) 138 SB 2044 778 53 (by ) 65 SB 2109 778 142 (multiple) 142 SB 1238 828 181 (messages, ) 185 SB 1423 828 63 (the ) 67 SB 1490 828 74 (two ) 78 SB 1568 828 156 (numbers ) 161 SB 1729 828 63 (are ) 68 SB 1797 828 65 (not ) 70 SB 1867 828 199 (necessarily ) 204 SB 2071 828 63 (the ) 68 SB 2139 828 112 (same.\)) 112 SB 1238 878 41 (A ) 48 SB 1286 878 130 (TWOS ) 137 SB 1423 878 67 (run ) 74 SB 1497 878 93 (must ) 100 SB 1597 878 147 (produce ) 154 SB 1751 878 134 (exactly ) 141 SB 1892 878 63 (the ) 70 SB 1962 878 98 (same ) 106 SB 2068 878 140 (number ) 148 SB 2216 878 35 (of) 35 SB 1238 928 193 (committed ) 195 SB 1433 928 170 (messages ) 172 SB 1605 928 72 (and ) 74 SB 1679 928 193 (committed ) 196 SB 1875 928 130 (events. ) 133 SB 2008 928 11 ( ) 14 SB 2022 928 130 (TWOS ) 133 SB 2155 928 96 (prints) 96 SB 1238 978 63 (the ) 67 SB 1305 978 140 (number ) 144 SB 1449 978 46 (of ) 50 SB 1499 978 193 (committed ) 197 SB 1696 978 170 (messages ) 174 SB 1870 978 72 (and ) 76 SB 1946 978 193 (committed ) 197 SB 2143 978 108 (events) 108 SB 1238 1028 42 (at ) 45 SB 1283 1028 63 (the ) 66 SB 1349 1028 72 (end ) 75 SB 1424 1028 46 (of ) 49 SB 1473 1028 63 (the ) 67 SB 1540 1028 78 (run. ) 82 SB 1622 1028 11 ( ) 15 SB 1637 1028 60 (By ) 64 SB 1701 1028 164 (checking ) 168 SB 1869 1028 98 (these ) 102 SB 1971 1028 156 (numbers ) 160 SB 2131 1028 120 (against) 120 SB 1238 1078 63 (the ) 74 SB 1312 1078 156 (numbers ) 167 SB 1479 1078 168 (produced ) 180 SB 1659 1078 53 (by ) 65 SB 1724 1078 63 (the ) 75 SB 1799 1078 183 (sequential ) 195 SB 1994 1078 135 (version ) 147 SB 2141 1078 46 (of ) 58 SB 2199 1078 52 (the) 52 SB 1238 1128 123 (applica) 123 SB 1361 1128 88 (tion, ) 89 SB 1450 1128 46 (or ) 47 SB 1497 1128 156 (previous ) 157 SB 1654 1128 139 (parallel ) 140 SB 1794 1128 94 (runs, ) 95 SB 1889 1128 130 (TWOS ) 131 SB 2020 1128 70 (can ) 71 SB 2091 1128 110 (check ) 111 SB 2202 1128 49 (for) 49 SB 1238 1178 487 (obviously non-deterministic ) 488 SB 1726 1178 132 (results. ) 133 SB 1859 1178 11 ( ) 12 SB 1871 1178 102 (\(Two ) 103 SB 1974 1178 157 (different ) 158 SB 2132 1178 83 (runs ) 84 SB 2216 1178 35 (of) 35 SB 1238 1228 63 (the ) 71 SB 1309 1228 98 (same ) 106 SB 1415 1228 85 (appli) 85 SB 1500 1228 115 (cation ) 123 SB 1623 1228 105 (could ) 113 SB 1736 1228 147 (produce ) 155 SB 1891 1228 63 (the ) 71 SB 1962 1228 98 (same ) 106 SB 2068 1228 140 (number ) 148 SB 2216 1228 35 (of) 35 SB 1238 1278 170 (messages ) 186 SB 1424 1278 72 (and ) 88 SB 1512 1278 119 (events ) 135 SB 1647 1278 140 (without ) 156 SB 1803 1278 105 (being ) 121 SB 1924 1278 134 (exactly ) 150 SB 2074 1278 63 (the ) 79 SB 2153 1278 98 (same.) 98 SB 1238 1328 112 (These ) 116 SB 1354 1328 157 (statistics ) 161 SB 1515 1328 116 (would ) 120 SB 1635 1328 65 (not ) 69 SB 1704 1328 113 (detect ) 117 SB 1821 1328 300 (non-determinism ) 304 SB 2125 1328 44 (in ) 49 SB 2174 1328 77 (such) 77 SB 1238 1378 111 (cases. ) 125 SB 1363 1378 11 ( ) 25 SB 1388 1378 176 (However, ) 191 SB 1579 1378 63 (the ) 78 SB 1657 1378 77 (size ) 92 SB 1749 1378 72 (and ) 87 SB 1836 1378 202 (complexity ) 217 SB 2053 1378 46 (of ) 61 SB 2114 1378 63 (the ) 78 SB 2192 1378 59 (test) 59 SB 1238 1428 216 (applications ) 232 SB 1470 1428 103 (make ) 119 SB 1589 1428 88 (such ) 104 SB 1693 1428 104 (coinci) 104 SB 1797 1428 126 (dences ) 142 SB 1939 1428 161 (unlikely. ) 177 SB 2116 1428 11 ( ) 27 SB 2143 1428 39 (If ) 56 SB 2199 1428 52 (the) 52 SB 1238 1478 187 (possibility ) 188 SB 1426 1478 46 (of ) 47 SB 1473 1478 96 (them ) 97 SB 1570 1478 114 (seems ) 115 SB 1685 1478 97 (high, ) 98 SB 1783 1478 84 (then ) 85 SB 1868 1478 81 (user ) 82 SB 1950 1478 94 (level ) 96 SB 2046 1478 121 (results ) 123 SB 2169 1478 82 (from) 82 SB 1238 1528 63 (the ) 74 SB 1312 1528 190 (simulation ) 201 SB 1513 1528 96 (itself ) 107 SB 1620 1528 70 (can ) 81 SB 1701 1528 51 (be ) 62 SB 1763 1528 150 (checked ) 161 SB 1924 1528 131 (against ) 142 SB 2066 1528 63 (the ) 75 SB 2141 1528 110 (proper) 110 SB 1238 1578 155 (answer.\) ) 160 SB 1398 1578 11 ( ) 16 SB 1414 1578 46 (In ) 51 SB 1465 1578 194 (production ) 199 SB 1664 1578 116 (mode, ) 122 SB 1786 1578 63 (the ) 69 SB 1855 1578 81 (user ) 87 SB 1942 1578 127 (clearly ) 133 SB 2075 1578 116 (would ) 122 SB 2197 1578 54 (not) 54 SB 1238 1628 103 (make ) 106 SB 1344 1628 30 (a ) 34 SB 1378 1628 117 (sequen) 117 SB 1495 1628 66 (tial ) 70 SB 1565 1628 67 (run ) 71 SB 1636 1628 44 (to ) 48 SB 1684 1628 115 (match ) 119 SB 1803 1628 105 (every ) 109 SB 1912 1628 139 (parallel ) 143 SB 2055 1628 67 (run ) 71 SB 2126 1628 72 (just ) 76 SB 2202 1628 49 (for) 49 SB 1238 1678 160 (purposes ) 161 SB 1399 1678 46 (of ) 47 SB 1446 1678 181 (validating ) 182 SB 1628 1678 151 (determin) 151 SB 1779 1678 83 (ism. ) 84 SB 1863 1678 11 ( ) 13 SB 1876 1678 72 (But ) 74 SB 1950 1678 37 (if ) 39 SB 1989 1678 63 (the ) 65 SB 2054 1678 139 (parallel ) 141 SB 2195 1678 56 (run) 56 SB 1238 1728 168 (produced ) 179 SB 1417 1728 186 (suspicious ) 197 SB 1614 1728 157 (answers, ) 169 SB 1783 1728 102 (using ) 114 SB 1897 1728 151 (TWSIM ) 163 SB 2060 1728 44 (to ) 56 SB 2116 1728 135 (validate) 135 SB 1238 1778 933 (determinism would be a good place to start debugging.) 933 SB 1238 1878 46 (In ) 50 SB 1288 1878 105 (many ) 110 SB 1398 1878 111 (cases, ) 116 SB 1514 1878 211 (mismatches ) 216 SB 1730 1878 53 (on ) 58 SB 1788 1878 63 (the ) 68 SB 1856 1878 193 (committed ) 198 SB 2054 1878 157 (statistics ) 162 SB 2216 1878 35 (of) 35 SB 1238 1928 51 (an ) 57 SB 1295 1928 200 (application ) 206 SB 1501 1928 91 (have ) 97 SB 1598 1928 164 (signalled ) 171 SB 1769 1928 109 (errors ) 116 SB 1885 1928 44 (in ) 51 SB 1936 1928 141 (TWOS. ) 148 SB 2084 1928 11 ( ) 18 SB 2102 1928 107 (Some ) 114 SB 2216 1928 35 (of) 35 SB 1238 1978 98 (these ) 114 SB 1352 1978 109 (errors ) 125 SB 1477 1978 91 (have ) 107 SB 1584 1978 91 (been ) 107 SB 1691 1978 127 (related ) 143 SB 1834 1978 119 (purely ) 135 SB 1969 1978 44 (to ) 60 SB 2029 1978 222 (deterministic) 222 SB 1238 2028 172 (concerns, ) 191 SB 1429 2028 88 (such ) 107 SB 1536 2028 46 (as ) 65 SB 1601 2028 63 (the ) 82 SB 1683 2028 138 (method ) 158 SB 1841 2028 46 (of ) 66 SB 1907 2028 154 (ordering ) 174 SB 2081 2028 170 (messages.) 170 SB 1238 2078 134 (Others, ) 136 SB 1374 2078 167 (however, ) 170 SB 1544 2078 91 (have ) 94 SB 1638 2078 91 (been ) 94 SB 1732 2078 223 (fundamental ) 226 SB 1958 2078 109 (errors ) 112 SB 2070 2078 75 (like ) 78 SB 2148 2078 103 (losing) 103 SB 1238 2128 181 (messages, ) 190 SB 1428 2128 122 (failing ) 132 SB 1560 2128 44 (to ) 54 SB 1614 2128 70 (roll ) 80 SB 1694 2128 91 (back ) 101 SB 1795 2128 165 (properly, ) 175 SB 1970 2128 46 (or ) 56 SB 2026 2128 109 (errors ) 119 SB 2145 2128 44 (in ) 54 SB 2199 2128 52 (the) 52 SB 1238 2178 194 (scheduling ) 196 SB 1434 2178 203 (algorithms. ) 205 SB 1639 2178 11 ( ) 13 SB 1652 2178 98 (Even ) 100 SB 1752 2178 37 (if ) 39 SB 1791 2178 72 (one ) 74 SB 1865 2178 93 (were ) 96 SB 1961 2178 131 (willing ) 134 SB 2095 2178 44 (to ) 47 SB 2142 2178 109 (accept) 109 SB 1238 2228 30 (a ) 33 SB 1271 2228 127 (certain ) 130 SB 1401 2228 300 (non-determinism ) 303 SB 1704 2228 44 (in ) 47 SB 1751 2228 63 (the ) 67 SB 1818 2228 132 (results, ) 136 SB 1954 2228 98 (these ) 102 SB 2056 2228 195 (phenomena) 195 SB 1238 2278 105 (could ) 107 SB 1345 2278 86 (only ) 88 SB 1433 2278 51 (be ) 53 SB 1486 2278 159 (regarded ) 161 SB 1647 2278 46 (as ) 48 SB 1695 2278 109 (errors ) 111 SB 1806 2278 166 (requiring ) 168 SB 1974 2278 194 (correction. ) 197 SB 2171 2278 11 ( ) 14 SB 2185 2278 66 (The) 66 SB 1238 2328 122 (failure ) 123 SB 1361 2328 46 (of ) 47 SB 1408 2328 144 (TWOS\222 ) 145 SB 1553 2328 151 (determin) 151 SB 1704 2328 72 (ism ) 74 SB 1778 2328 142 (brought ) 144 SB 1922 2328 96 (them ) 98 SB 2020 2328 44 (to ) 46 SB 2066 2328 89 (light ) 91 SB 2157 2328 94 (much) 94 SB 1238 2378 98 (more ) 104 SB 1342 2378 138 (quickly ) 144 SB 1486 2378 84 (than ) 90 SB 1576 2378 37 (if ) 43 SB 1619 2378 60 (we ) 67 SB 1686 2378 72 (had ) 79 SB 1765 2378 65 (not ) 72 SB 1837 2378 185 (demanded ) 192 SB 2029 2378 222 (deterministic) 222 SB 1238 2428 481 (results from the mechanism.) 481 SB 1238 2528 100 (Once ) 121 SB 1359 2528 88 (such ) 109 SB 1468 2528 30 (a ) 51 SB 1519 2528 152 (problem ) 173 SB 1692 2528 67 (has ) 88 SB 1780 2528 91 (been ) 112 SB 1892 2528 164 (detected, ) 185 SB 2077 2528 63 (the ) 85 SB 2162 2528 89 (usual) 89 SB 1238 2578 195 (difficulties ) 198 SB 1436 2578 46 (of ) 49 SB 1485 2578 189 (debugging ) 192 SB 1677 2578 139 (parallel ) 142 SB 1819 2578 46 (or ) 50 SB 1869 2578 192 (distributed ) 196 SB 2065 2578 91 (code ) 95 SB 2160 2578 91 (arise.) 91 SB 1238 2628 118 (Often, ) 125 SB 1363 2628 63 (the ) 70 SB 1433 2628 93 (error ) 100 SB 1533 2628 182 (producing ) 190 SB 1723 2628 162 (incorrect ) 170 SB 1893 2628 193 (committed ) 201 SB 2094 2628 121 (results ) 129 SB 2223 2628 28 (is) 28 SB 1238 2678 1013 (itself non-deterministic, so it may not appear on subsequent) 1013 SB 1238 2728 94 (runs. ) 117 SB 1355 2728 11 ( ) 34 SB 1389 2728 199 (Sometimes ) 222 SB 1611 2728 63 (the ) 86 SB 1697 2728 152 (problem ) 175 SB 1872 2728 39 (is ) 62 SB 1934 2728 107 (based ) 130 SB 2064 2728 53 (on ) 76 SB 2140 2728 111 (timing) 111 SB 1238 2778 266 (considerations, ) 275 SB 1513 2778 48 (so ) 57 SB 1570 2778 159 (inserting ) 168 SB 1738 2778 103 (debug) 103 SB 1841 2778 86 (ging ) 95 SB 1936 2778 91 (code ) 100 SB 2036 2778 70 (can ) 79 SB 2115 2778 103 (make ) 112 SB 2227 2778 24 (it) 24 SB 1238 2828 184 (disappear. ) 186 SB 1424 2828 11 ( ) 13 SB 1437 2828 176 (However, ) 179 SB 1616 2828 51 (an ) 54 SB 1670 2828 93 (error ) 96 SB 1766 2828 118 (whose ) 121 SB 1887 2828 168 (symptom ) 171 SB 2058 2828 39 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