APPARENT DEADLOCK!!! Creating emergency threads for unassigned pending tasks!

My c3p0 version is
compile 'com.mchange:c3p0:0.9.1.2'

[1] Error 

WARN   run, com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@c3d2e5 -- APPARENT DEADLOCK!!! Creating emergency threads for unassigned pending tasks!
WARN   run, com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@c3d2e5 -- APPARENT DEADLOCK!!! Complete Status: 
 Managed Threads: 3
 Active Threads: 3
 Active Tasks: 
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@1556819 (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2)
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@254f54 (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0)
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@17b15ec (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1)
 Pending Tasks: 
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@1dc5047
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@11a9ca3
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@21b8e1
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@1f0c306
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@193e3d0
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@5174ad
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@1c325b7
Pool thread stack traces:
 Thread[com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2,5,main]
  java.lang.Thread.sleep(Native Method)
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1805)
  com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
 Thread[com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0,5,main]
  java.lang.Thread.sleep(Native Method)
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1805)
  com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
 Thread[com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1,5,main]
  java.lang.Thread.sleep(Native Method)
  com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1805)
  com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

C3po

[2] Pooled DataSource / jpa-context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc"
 xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
 xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
  http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd 
  http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
  http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd"
 default-autowire="byName">


  <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">
  <property name="driverClass" value="${db.driver}"/>
  <property name="jdbcUrl" value="${db.url}"/>
  <property name="user" value="${db.username}"/>
  <property name="password" value="${db.password}"/>
  <property name="minPoolSize" value="${db.poolsize.min}"/>
  <property name="maxPoolSize" value="${db.poolsize.max}"/>
  <property name="maxStatementsPerConnection" value="15"/>
  <property name="idleConnectionTestPeriod" value="3000"/>
 </bean>

</beans>

hibernate.cfg.xml is : 

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
  "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
  "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
 <session-factory>
  <property name="hibernate.default_batch_fetch_size">16</property>
  <property name="hibernate.max_fetch_depth">5</property>

   <property name="hibernate.cache.use_query_cache">false</property>
  <property name="hibernate.cache.use_second_level_cache">false</property>
  <property name="hibernate.cache.provider_class">org.hibernate.cache.EhCacheProvider</property> 
  
  <!-- property name="show_sql">true</property-->
        <!--property name="format_sql">true</property-->
        <!--property name="use_sql_comments">true</property-->

  </session-factory>
</hibernate-configuration>

db.properties

db.username=root
db.password=mysql55
db.url=jdbc:mysql://localhost/eccount
db.dialect=org.hibernate.dialect.MySQL5Dialect
db.driver=com.mysql.jdbc.Driver
db.generateDdl=false
db.showSql=false

db.persistenceUnit=eccount

db.generateDdl=true
db.poolsize.max=100
db.poolsize.min=10
# turn on statement pooling

[3] PROPOSED SOLUTION

For version 0.9.2 of c3p0 (compile 'com.mchange:c3p0:0.9.2'), 

[1] Configure Statement Pooling
1.1 statementCacheNumDeferredCloseThreads="1"

If statementCacheNumDeferredCloseThreads is > zero, 
the Statement pool will defer physically close()ing cached Statements until its parent Connection is not   in use by any client or internally (in e.g. a test) by the pool itself.
For some JDBC drivers (especially Oracle), attempts to close a Statement freeze if the parent Connection is in use.
This parameter defaults to 0.

Set it to a positive value if you observe "APPARENT DEADLOCKS" realted to Connection close tasks.
Almost always, that value should be one: if you need more than one Thread dedicated solely to Statement destruction, you probably should set maxStatements and/or maxStatementsPerConnection to higher values so you don't churn through cached Statements so quickly.



SOLUTION IN MY CASE
Restart mysql server.

REFERENCES
Configuring Statement Pooling
http://www.mchange.com/projects/c3p0/#configuring_statement_pooling

c3p0 - JDBC3 Connection and Statement Pooling,  http://www.mchange.com/projects/c3p0/#numHelperThreads

What are the required C3P0 settings for hibernate in order to avoid Deadlocks, http://stackoverflow.com/a/3731978/432903

c3p0 apparent deadlock / creating emergency threads, https://forum.hibernate.org/viewtopic.php?t=947246&highlight=apparent+deadlock+c3p0

java+hibernate webservice - apperant deadlock,
http://stackoverflow.com/a/11669290/432903

c3p0 - JDBC3 Connection and Statement Pooling, http://www.mchange.com/projects/c3p0/#configuration_files

Best way of database pooling in spring for production system,
http://stackoverflow.com/a/14548122/432903

http://stackoverflow.com/a/12088523/432903