Hu, ZhangHao wrote: > Hi All > > > > I am using commons-dbcp-1.2.2 + common-pools-1.5.2 and meet a dead-lock > problem. > > The problem is if all connections in the thread pool are occupied, and > other threads are waiting for db connection. > > Then if those threads received InterruptedException, then the thread > pool will be dead and can't be used any more. > > > > But commons-dbcp-1.2.2 + common-pools-1.4 can work will with same > setting and same test program. > > The new version can't work properly with commons-dbcp-1.2.2? (I also try > commons-dbcp-1.4 + common-pools-1.5.2, it can't work too...) > > Any suggestions are appreciated. >
Thank you for reporting this. Unfortunately, this looks like a pool bug. It is being tracked as POOL-162 in JIRA (https://issues.apache.org/jira/browse/POOL-162). The only workaround that I can suggest immediately is to avoid interrupting threads blocked waiting on the pool, possibly using a positive maxWait value as an alternative means of controlling blocked waits. Comments on the ticket are welcome. The fix looks simple. Assuming I am right on this, we should get this patched ASAP. Phil > > > The configuration for dbcp is as follow: > > dal.connectionProperties=autoReconnect=true; > > dal.initialSize=0 > > dal.maxActive=1 > > dal.maxIdle=1 > > dal.minIdle=0 > > dal.maxWait=-1 > > dal.validationQuery=select 1 > > dal.testOnBorrow=true > > dal.testOnReturn=false > > dal.testWhileIdle=true > > dal.timeBetweenEvictionRunsMillis=60000 > > dal.numTestsPerEvictionRun=3 > > dal.minEvictableIdleTimeMillis=60000 > > dal.poolPreparedStatements=true > > dal.maxOpenPreparedStatements=20 > > > > The test program is as follow: > > > > package db.test; > > > > import java.util.List; > > import com.telenav.dal.content.verse.crawler.ISiteDefinition; > > import com.telenav.dal.content.verse.crawler.PageCrawlTaskDao; > > import com.telenav.dal.content.verse.crawler.SiteDefinitionDao; > > > > public class TestConnection { > > public static void main(String[] args) throws Exception { > > Runnable t1 = new Runnable() { > > @Override > > public void run() { > > int cnt = 0; > > try { > > cnt = > PageCrawlTaskDao.getInstance().getCountAllPageTask(1); // a > time-consuming db operation, it will occupy the connection for some time > > } > > catch ( Exception e ) { > > > System.out.println("------------------------------------------------"); > > e.printStackTrace(); > > } > > > > System.out.println(cnt); > > } > > }; > > > > Runnable t2 = new Runnable() { > > @Override > > public void run() { > > int cnt = 0; > > try { > > cnt = > PageCrawlTaskDao.getInstance().getCountAllPageTask(1); > > } > > catch ( Exception e ) { > > System.out.println("catch exception: " + > Thread.currentThread().getName()); > > //e.printStackTrace(); > > } > > > > System.out.println("thread " + > Thread.currentThread().getName() + " : " + cnt); > > } > > }; > > > > Thread tt1 = new Thread(t1); > > tt1.start(); > > Thread.sleep(2000); > > tt1.interrupt(); > > > > int i = 0; > > while ( i < 20 ) { > > Thread tt2 = new Thread(t2, Integer.toString(i)); > > tt2.start(); > > Thread.sleep(1000); > > if(i == 3) > > tt2.interrupt(); > > i ++; > > } > > > > //tt1.interrupt(); > > > > Thread.sleep(60000); > > > System.out.println("xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"); > > > > List<ISiteDefinition> sites = null; > > while ( true ) { > > try { > > // The main thread can't get any > connection here..... > > sites = > SiteDefinitionDao.getInstance().getAllSiteDefinitions(); // a > non-time-consuming db operation to show the db connection pool is > correct to use > > } > > catch (Exception e ) { > > e.printStackTrace(); > > } > > > > if ( sites != null ) { > > for ( ISiteDefinition site : sites ) { > > System.out.println(site.getUrl()); > > } > > } > > Thread.sleep(5000); > > } > > } > > } > > > > > > Best wishes, > > Hu Zhanghao > > > > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
