a

Author: selimslab

_CONTENT/eng/data/acid.md _CONTENT/eng/db/acid.md_CONTENT/eng/data/acid.md renamed to _CONTENT/eng/db/acid.md

@@ -43,6 +43,17 @@ better compression and disk life
 10x write throughput vs b-tree, 0.5x read/s
 less stable response times in higher percentiles
 
+## lsm 
+  wal
+  memtable 
+  sstable
+    bloom
+    sparse index
+    block index 
+  compaction 
+    L0, L1, ..
+  delete by tombstones 
+  
 
 ## columnar vs wide column
 both lsm

_CONTENT/eng/pl/lang.md _CONTENT/eng/db/db.md_CONTENT/eng/pl/lang.md renamed to _CONTENT/eng/db/db.md

@@ -0,0 +1,45 @@
+---
+---
+```
+bit
+  get:     & 1<<i
+  set:     | 1<<i
+
+  clear:   & ~(1<<i)
+  lastbit: & 1
+
+  -1 << (i+1)
+  1111 << 2 = 1100
+
+  (1<<i)-1
+  (1<<2)-1
+  0100 - 0001 = 0011
+
+str
+  rk
+  lps + kmp
+  trie
+
+array
+
+stack
+q
+monotonic
+
+hashmap
+
+linked-list
+skip-list
+
+graph
+  topo: kahns or
+    dfs from all
+    visit after neighbors
+    reverse
+
+  paths
+    dijkstra_priority = new_cost
+    greedy_priority = heuristic(goal,next)
+    a_star_priority = new_cost + heuristic(goal,next)
+```
+

_CONTENT/eng/data/isolation.md _CONTENT/eng/db/isolation.md_CONTENT/eng/data/isolation.md renamed to _CONTENT/eng/db/isolation.md

@@ -0,0 +1,12 @@
+---
+---
+skiplist: levels of linked lists
+
+### sets
+membership: bloom filter (k hash funcs + bit array)
+cardinality: hyperloglog: hash items and count leading zeros. longest run of zeros ≈ log₂(cardinality)
+similarity: convert sets to hash signs. minhash, locality sensitive hashing
+
+### streams
+overestimate freq with count-min-sketch
+sample k random items with reservoir samp: Fill reservoir with first k elements. For ith stream item, replace if a random num in [1,i] <=k

_CONTENT/eng/data/layout.md _CONTENT/eng/db/layout.md_CONTENT/eng/data/layout.md renamed to _CONTENT/eng/db/layout.md

@@ -1,5 +1,42 @@
 ---
 ---
+control plane 
+    api-server
+    etcd 
+    scheduler 
+    controller-manager 
+
+  node
+    kubelet 
+    kube-proxy
+    coredns 
+    
+  namespace 
+
+    deployment 
+      daemonset
+      statefulset 
+      replicaset 
+        pod 
+          container 
+
+    resource quota
+
+    pvc
+    
+    network policy 
+    service 
+    endpoint 
+    ingress 
+
+    service account 
+    rbac role 
+    configmap 
+    secret 
+    
+    hpa/vpa pod auto scaler
+
+
 ```
 control plane
   kube-apiserver