Looks like one hope/theory knocked on the head

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Now I have mapped the speed of OPT and LRU using a traditional two level memory hierarchy, my task is to find something better that might make NoC a more viable computing platform.

One thought that occurred to me was that the preference of C and similar languages for page aligned memory in certain situations might make it feasible or reasonable to cache the first 128 bits (16 bytes) in faster access memory.

So I wrote some code to test which 16 byte “segments” of a page were accessed by code.

The list that follows is for read/write accesses (i.e. not instructions). I will get around to plotting a graph, but it looks like that idea – which was always a bit of a straw clutching exercise – is not going to fly.

 

Segment: 0 Count: 3145700

Segment: 1 Count: 4892407

Segment: 2 Count: 3207293

Segment: 3 Count: 3790303

Segment: 4 Count: 5315932

Segment: 5 Count: 8143085

Segment: 6 Count: 6060159

Segment: 7 Count: 3900910

Segment: 8 Count: 10018940

Segment: 9 Count: 3738990

Segment: 10 Count: 3654813

Segment: 11 Count: 3887982

Segment: 12 Count: 4046926

Segment: 13 Count: 7366857

Segment: 14 Count: 5029997

Segment: 15 Count: 5555853

Segment: 16 Count: 5101695

Segment: 17 Count: 4919006

Segment: 18 Count: 5536030

Segment: 19 Count: 3679621

Segment: 20 Count: 3496416

Segment: 21 Count: 4175369

Segment: 22 Count: 4126270

Segment: 23 Count: 3264013

Segment: 24 Count: 4100255

Segment: 25 Count: 4322633

Segment: 26 Count: 9749020

Segment: 27 Count: 19622721

Segment: 28 Count: 11919679

Segment: 29 Count: 3679721

Segment: 30 Count: 8063852

Segment: 31 Count: 11752619

Segment: 32 Count: 23894391

Segment: 33 Count: 14935880

Segment: 34 Count: 17010081

Segment: 35 Count: 12806447

Segment: 36 Count: 11758764

Segment: 37 Count: 13757944

Segment: 38 Count: 5967876

Segment: 39 Count: 8410322

Segment: 40 Count: 9751409

Segment: 41 Count: 10568546

Segment: 42 Count: 8047474

Segment: 43 Count: 9064589

Segment: 44 Count: 9219878

Segment: 45 Count: 7913851

Segment: 46 Count: 4868922

Segment: 47 Count: 5057902

Segment: 48 Count: 6649602

Segment: 49 Count: 8562603

Segment: 50 Count: 3609239

Segment: 51 Count: 3965129

Segment: 52 Count: 4869654

Segment: 53 Count: 5149858

Segment: 54 Count: 2055722

Segment: 55 Count: 32499129

Segment: 56 Count: 2733892

Segment: 57 Count: 8887833

Segment: 58 Count: 2329809

Segment: 59 Count: 2946391

Segment: 60 Count: 2946919

Segment: 61 Count: 8444848

Segment: 62 Count: 2890405

Segment: 63 Count: 3106806

Segment: 64 Count: 3349164

Segment: 65 Count: 4892046

Segment: 66 Count: 4453014

Segment: 67 Count: 4943979

Segment: 68 Count: 4595481

Segment: 69 Count: 6552969

Segment: 70 Count: 15521259

Segment: 71 Count: 4037689

Segment: 72 Count: 3737825

Segment: 73 Count: 5438653

Segment: 74 Count: 5012634

Segment: 75 Count: 4229649

Segment: 76 Count: 11143742

Segment: 77 Count: 6171722

Segment: 78 Count: 11938365

Segment: 79 Count: 11041493

Segment: 80 Count: 6030829

Segment: 81 Count: 9557385

Segment: 82 Count: 23490594

Segment: 83 Count: 9314300

Segment: 84 Count: 11119997

Segment: 85 Count: 8870504

Segment: 86 Count: 9059886

Segment: 87 Count: 4581160

Segment: 88 Count: 13002081

Segment: 89 Count: 6050274

Segment: 90 Count: 4850064

Segment: 91 Count: 4495531

Segment: 92 Count: 6551494

Segment: 93 Count: 6294404

Segment: 94 Count: 5852555

Segment: 95 Count: 9759357

Segment: 96 Count: 5688209

Segment: 97 Count: 9991460

Segment: 98 Count: 5155181

Segment: 99 Count: 3923768

Segment: 100 Count: 3319723

Segment: 101 Count: 8659639

Segment: 102 Count: 4416737

Segment: 103 Count: 2534491

Segment: 104 Count: 2470280

Segment: 105 Count: 2709695

Segment: 106 Count: 2535015

Segment: 107 Count: 3050061

Segment: 108 Count: 2772341

Segment: 109 Count: 3621580

Segment: 110 Count: 3332878

Segment: 111 Count: 4358518

Segment: 112 Count: 4282092

Segment: 113 Count: 3523498

Segment: 114 Count: 3111625

Segment: 115 Count: 3474108

Segment: 116 Count: 2809375

Segment: 117 Count: 3592879

Segment: 118 Count: 2768848

Segment: 119 Count: 10525789

Segment: 120 Count: 4122297

Segment: 121 Count: 3660249

Segment: 122 Count: 3432971

Segment: 123 Count: 3671499

Segment: 124 Count: 3066933

Segment: 125 Count: 3271576

Segment: 126 Count: 7069611

Segment: 127 Count: 3774229

Segment: 128 Count: 3258290

Segment: 129 Count: 2416892

Segment: 130 Count: 3413264

Segment: 131 Count: 2789339

Segment: 132 Count: 7841394

Segment: 133 Count: 2992968

Segment: 134 Count: 3624867

Segment: 135 Count: 3304507

Segment: 136 Count: 3573405

Segment: 137 Count: 4226925

Segment: 138 Count: 4803447

Segment: 139 Count: 5630354

Segment: 140 Count: 6420305

Segment: 141 Count: 4721786

Segment: 142 Count: 4860223

Segment: 143 Count: 4183175

Segment: 144 Count: 3790705

Segment: 145 Count: 7974241

Segment: 146 Count: 4146253

Segment: 147 Count: 3063269

Segment: 148 Count: 3485084

Segment: 149 Count: 2923729

Segment: 150 Count: 2947715

Segment: 151 Count: 3818073

Segment: 152 Count: 2769076

Segment: 153 Count: 2645308

Segment: 154 Count: 4452525

Segment: 155 Count: 4793146

Segment: 156 Count: 2281903

Segment: 157 Count: 3256076

Segment: 158 Count: 2414992

Segment: 159 Count: 2951958

Segment: 160 Count: 1747487

Segment: 161 Count: 2385269

Segment: 162 Count: 4128250

Segment: 163 Count: 5101661

Segment: 164 Count: 3579155

Segment: 165 Count: 3746030

Segment: 166 Count: 3117725

Segment: 167 Count: 3516756

Segment: 168 Count: 6842484

Segment: 169 Count: 2145906

Segment: 170 Count: 2281955

Segment: 171 Count: 3043248

Segment: 172 Count: 2946803

Segment: 173 Count: 2638829

Segment: 174 Count: 3543883

Segment: 175 Count: 3509146

Segment: 176 Count: 7295889

Segment: 177 Count: 3061840

Segment: 178 Count: 4201176

Segment: 179 Count: 22324025

Segment: 180 Count: 7157776

Segment: 181 Count: 14223711

Segment: 182 Count: 5079461

Segment: 183 Count: 6497476

Segment: 184 Count: 3395786

Segment: 185 Count: 3594557

Segment: 186 Count: 4511617

Segment: 187 Count: 3377908

Segment: 188 Count: 4015556

Segment: 189 Count: 3884031

Segment: 190 Count: 4418048

Segment: 191 Count: 4425675

Segment: 192 Count: 4151888

Segment: 193 Count: 4073928

Segment: 194 Count: 7515643

Segment: 195 Count: 4260252

Segment: 196 Count: 15629731

Segment: 197 Count: 8020217

Segment: 198 Count: 8051874

Segment: 199 Count: 8100937

Segment: 200 Count: 4875180

Segment: 201 Count: 6493053

Segment: 202 Count: 5447678

Segment: 203 Count: 5587693

Segment: 204 Count: 4748458

Segment: 205 Count: 5004972

Segment: 206 Count: 6418567

Segment: 207 Count: 10145254

Segment: 208 Count: 5678528

Segment: 209 Count: 5601157

Segment: 210 Count: 5702977

Segment: 211 Count: 5590463

Segment: 212 Count: 6693545

Segment: 213 Count: 4030951

Segment: 214 Count: 5199543

Segment: 215 Count: 7942092

Segment: 216 Count: 6376629

Segment: 217 Count: 7480443

Segment: 218 Count: 5150624

Segment: 219 Count: 4318579

Segment: 220 Count: 4535156

Segment: 221 Count: 3908294

Segment: 222 Count: 4547756

Segment: 223 Count: 4509968

Segment: 224 Count: 2944729

Segment: 225 Count: 3301802

Segment: 226 Count: 3638158

Segment: 227 Count: 4838325

Segment: 228 Count: 9253359

Segment: 229 Count: 2775284

Segment: 230 Count: 3601569

Segment: 231 Count: 3482137

Segment: 232 Count: 3594477

Segment: 233 Count: 2952485

Segment: 234 Count: 3315834

Segment: 235 Count: 2438082

Segment: 236 Count: 4846832

Segment: 237 Count: 2711387

Segment: 238 Count: 5907452

Segment: 239 Count: 3551899

Segment: 240 Count: 3621086

Segment: 241 Count: 3032466

Segment: 242 Count: 3572000

Segment: 243 Count: 3020379

Segment: 244 Count: 3275738

Segment: 245 Count: 3398733

Segment: 246 Count: 4023338

Segment: 247 Count: 3839542

Segment: 248 Count: 6434160

Segment: 249 Count: 3999611

Segment: 250 Count: 4388716

Segment: 251 Count: 8178958

Segment: 252 Count: 3622946

Segment: 253 Count: 3564538

Segment: 254 Count: 3182242

Segment: 255 Count: 3133097

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