update

.idea/workspace.xml

@@ -261,14 +261,7 @@
       <workItem from="1588302756697" duration="3701000" />
       <workItem from="1588749661816" duration="451000" />
       <workItem from="1589857792404" duration="221000" />
-      <workItem from="1591254276718" duration="1288000" />
-    </task>
-    <task id="LOCAL-00017" summary="update md">
-      <created>1581704713975</created>
-      <option name="number" value="00017" />
-      <option name="presentableId" value="LOCAL-00017" />
-      <option name="project" value="LOCAL" />
-      <updated>1581704713975</updated>
+      <workItem from="1591254276718" duration="1552000" />
     </task>
     <task id="LOCAL-00018" summary="update q10/q746">
       <created>1581705212871</created>
@@ -606,7 +599,14 @@
       <option name="project" value="LOCAL" />
       <updated>1591254334745</updated>
     </task>
-    <option name="localTasksCounter" value="66" />
+    <task id="LOCAL-00066" summary="update">
+      <created>1591262493149</created>
+      <option name="number" value="00066" />
+      <option name="presentableId" value="LOCAL-00066" />
+      <option name="project" value="LOCAL" />
+      <updated>1591262493149</updated>
+    </task>
+    <option name="localTasksCounter" value="67" />
     <servers />
   </component>
   <component name="TypeScriptGeneratedFilesManager">
@@ -691,16 +691,16 @@
       <screen x="0" y="0" width="1440" height="900" />
     </state>
     <state x="458" y="204" key="#com.intellij.refactoring.safeDelete.UnsafeUsagesDialog/0.0.1440.900@0.0.1440.900" timestamp="1587221348872" />
-    <state x="404" y="60" key="CommitChangelistDialog2" timestamp="1591254334575">
+    <state x="404" y="60" key="CommitChangelistDialog2" timestamp="1591262493032">
       <screen x="0" y="0" width="1920" height="1080" />
     </state>
     <state x="303" y="50" key="CommitChangelistDialog2/0.0.1440.900@0.0.1440.900" timestamp="1588749779133" />
-    <state x="404" y="60" key="CommitChangelistDialog2/0.0.1920.1080@0.0.1920.1080" timestamp="1591254334575" />
-    <state x="191" y="94" width="1152" height="720" key="DiffContextDialog" timestamp="1591254332165">
+    <state x="404" y="60" key="CommitChangelistDialog2/0.0.1920.1080@0.0.1920.1080" timestamp="1591262493032" />
+    <state x="191" y="94" width="1152" height="720" key="DiffContextDialog" timestamp="1591262490778">
       <screen x="0" y="0" width="1920" height="1080" />
     </state>
     <state x="143" y="78" width="1152" height="720" key="DiffContextDialog/0.0.1440.900@0.0.1440.900" timestamp="1588749770793" />
-    <state x="191" y="94" key="DiffContextDialog/0.0.1920.1080@0.0.1920.1080" timestamp="1591254332165" />
+    <state x="191" y="94" key="DiffContextDialog/0.0.1920.1080@0.0.1920.1080" timestamp="1591262490778" />
     <state x="144" y="78" width="1152" height="720" key="DiffContextDialog/0.23.1440.793@0.23.1440.793" timestamp="1582714686712" />
     <state x="143" y="78" width="1152" height="720" key="DiffContextDialog/0.23.1440.797@0.23.1440.797" timestamp="1588303139733" />
     <state width="1398" height="204" key="GridCell.Tab.0.bottom" timestamp="1587225087588">
@@ -747,11 +747,11 @@
       <screen x="0" y="0" width="1440" height="900" />
     </state>
     <state x="221" y="63" key="SettingsEditor/0.0.1440.900@0.0.1440.900" timestamp="1585223890241" />
-    <state x="427" y="228" key="Vcs.Push.Dialog.v2" timestamp="1591254336079">
+    <state x="427" y="228" key="Vcs.Push.Dialog.v2" timestamp="1591262494365">
       <screen x="0" y="0" width="1920" height="1080" />
     </state>
     <state x="320" y="190" key="Vcs.Push.Dialog.v2/0.0.1440.900@0.0.1440.900" timestamp="1588749781144" />
-    <state x="427" y="228" key="Vcs.Push.Dialog.v2/0.0.1920.1080@0.0.1920.1080" timestamp="1591254336079" />
+    <state x="427" y="228" key="Vcs.Push.Dialog.v2/0.0.1920.1080@0.0.1920.1080" timestamp="1591262494365" />
     <state x="100" y="100" width="1240" height="700" key="com.intellij.history.integration.ui.views.FileHistoryDialog" timestamp="1587219014962">
       <screen x="0" y="23" width="1440" height="797" />
     </state>

Rocket.md

@@ -165,7 +165,7 @@ Read View就是事务进行快照读操作的时候生产的读视图，在该
 
 ### Next-Key Lock
 
-InnoDB 采用 Next-Key Lock 解决幻读问题。在`insert into test(xid) values (1), (3), (5), (8), (11);`后，由于xid上是有索引的，该算法总是会去锁住索引记录。现在，该索引可能被锁住的范围如下：(-∞, 1], (1, 3], (3, 5], (5, 8], (8, 11], (11, +∞)。Session A执行后会锁住的范围：(5, 8], (8, 11]。除了锁住8所在的范围，还会锁住下一个范围，所谓Next-Key。
+InnoDB 采用 Next-Key Lock 解决幻读问题。在`insert into test(xid) values (1), (3), (5), (8), (11);`后，由于xid上是有索引的，该算法总是会去锁住索引记录。现在，该索引可能被锁住的范围如下：(-∞, 1], (1, 3], (3, 5], (5, 8], (8, 11], (11, +∞)。Session A（`select * from test where id = 8 for update`）执行后会锁住的范围：(5, 8], (8, 11]。除了锁住8所在的范围，还会锁住下一个范围，所谓Next-Key。
 
 ### Mysql的逻辑结构
 
@@ -515,6 +515,13 @@ AQS有两个队列，同步对列和条件队列。同步队列依赖一个双
 6. threadFactory：线程工厂，用于创建线程，一般用默认的即可。
 7. handler：拒绝策略。当任务太多来不及处理，如何拒绝任务。
 
+### 线程池都有哪几种工作队列
+
+1. ArrayBlockingQueue：底层是数组，有界队列，如果我们要使用生产者-消费者模式，这是非常好的选择。
+2. LinkedBlockingQueue：底层是链表，可以当做无界和有界队列来使用，所以大家不要以为它就是无界队列。
+3. SynchronousQueue：本身不带有空间来存储任何元素，使用上可以选择公平模式和非公平模式。
+4. PriorityBlockingQueue：无界队列，基于数组，数据结构为二叉堆，数组第一个也是树的根节点总是最小值。
+
 ### 线程池的拒绝策略
 
 1. ThreadPoolExecutor.AbortPolicy:丢弃任务并抛出RejectedExecutionException异常。