vault backup: 2025-03-18 08:34:12

.obsidian/workspace.json

@@ -4,7 +4,7 @@
     "type": "split",
     "children": [
       {
-        "id": "376bc91799eae4a7",
+        "id": "4c1f5b7a6abb1339",
         "type": "tabs",
         "children": [
           {
@@ -28,20 +28,36 @@
         "type": "tabs",
         "children": [
           {
-            "id": "51157f32453cba69",
+            "id": "e8fbc9b0750d5e3b",
             "type": "leaf",
             "state": {
               "type": "pdf",
               "state": {
                 "file": "Concurrent Systems/slides/class 5.pdf",
-                "page": 7,
+                "page": 8,
                 "left": -27,
-                "top": 68,
+                "top": 340,
                 "zoom": 0.5754156769596199
               },
               "icon": "lucide-file-text",
               "title": "class 5"
             }
+          },
+          {
+            "id": "51157f32453cba69",
+            "type": "leaf",
+            "state": {
+              "type": "pdf",
+              "state": {
+                "file": "Concurrent Systems/slides/class 6.pdf",
+                "page": 1,
+                "left": -34,
+                "top": 598,
+                "zoom": 0.4382422802850357
+              },
+              "icon": "lucide-file-text",
+              "title": "class 6"
+            }
           }
         ]
       }
@@ -216,10 +232,11 @@
       "companion:Toggle completion": false
     }
   },
-  "active": "51157f32453cba69",
+  "active": "6edd4157a160e462",
   "lastOpenFiles": [
-    "Concurrent Systems/notes/5 - Software Transactional Memory.md",
     "Concurrent Systems/slides/class 5.pdf",
+    "Concurrent Systems/notes/5 - Software Transactional Memory.md",
+    "Concurrent Systems/slides/class 6.pdf",
     "Concurrent Systems/notes/4c - Dining Philosophers.md",
     "Concurrent Systems/notes/4 - Semaphores.md",
     "Concurrent Systems/notes/4b - Monitors.md",
@@ -248,7 +265,6 @@
     "Pasted image 20250305182542.png",
     "HCIW/notes/1 - UX for IoT.md",
     "HCIW/exercises/Exercise.md",
-    "HCIW/exercises",
     "Concurrent Systems/notes/images/Pasted image 20250304082459.png",
     "Concurrent Systems/notes/images/Pasted image 20250304093223.png",
     "Concurrent Systems/notes/images/Pasted image 20250304090219.png",

Concurrent Systems/notes/5 - Software Transactional Memory.md

@@ -33,6 +33,7 @@ Implementation: every transaction uses a local working space
 #### A Logical Clock based STM system
 All the READs perform if no inconsistencies arise, or before any inconsistency
 
+(definizioni in def qua sotto)
 >[!def]
 >Let T be a transaction; its read prefix is formed by all its successful READ before its possible abortion.
 
@@ -108,18 +109,21 @@ VWC allows more transactions to commit -> it is a more liberal property than opa
 
 #### A Vector clock based STM system
 We have m shared MRMW registers; register X is represented by a pair XX, with:
-- XX.val the current value of X
+- `XX.val` the current value of X
-- XX.depend[1...m] a vector clock s.t.
+- `XX.depend[1...m]` a vector clock s.t.
-	- XX.depend[X] is the sequence number associated with the current value of X
+	- `XX.depend[X]` is the sequence number associated with the current value of X
-	- XX.depend[Y] is the sequence number associated with the value of Y on which the current value of X depends from
+		- corresponds to the `date` of the previous algorithm
+	- `XX.depend[Y]` is the sequence number associated with the value of Y on which the current value of X depends from
 - There is a starvation-free lock object associated to the pair
 
-We have n processes; process $p_i$ has
+So for X, I don't just have to track "who modified X", but also "who modified "Y or Z", if they may have influenced X.
-- for every X, a local copy lc(XX) of the implementation of X
-- $p\_depend_i[1…m]$ s.t. $p\_depend_i[X]$ is the seq.num. of the last val of X (directly or undirectly) known by $p_i$
 
-Every transaction T issues by pi has:
+We have n processes; process $p_i$ has
-- read_set(T) and write_set(T)
+- for every X, a local copy `lc(XX)` of the implementation of X
+- $p\_depend_i[1…m]$ s.t. $p\_depend_i[X]$ is the sequence number of the last val of X (directly or indirectly) known by $p_i$
+
+Every transaction T issues by $p_i$ has:
+- `read_set(T)` and `write_set(T)`
 - $t\_depend_{T}[1…m]$ a local copy of $p\_depend_i$ (this is used in the optimistic execution, not to change $p\_depend_{i}$ if T aborts)
 
 ```