Arch Linux

scott_fakename

Member

Registered: 2012-08-15

Posts: 92

Java GUI applications always hang when connected to the network

I have the java package installed on my computer from the arch repos. It always works, but whenever I am connected to the internet, anything swing-based takes inordinately long to load. Any java program that does NOT use swing runs just fine. Eclipse always takes a long time so it's difficult for me to tell if it's affected.

Running any application on java with the -verbose command line argument shows that it appears to be hanging on:

// Bunch of things omitted...
[Loaded java.net.InetAddressImplFactory from /usr/lib/jvm/java-7-openjdk/jre/lib/rt.jar]
[Loaded java.net.InetAddressImpl from /usr/lib/jvm/java-7-openjdk/jre/lib/rt.jar]
[Loaded java.net.Inet4AddressImpl from /usr/lib/jvm/java-7-openjdk/jre/lib/rt.jar]
[Loaded sun.net.spi.nameservice.NameService from /usr/lib/jvm/java-7-openjdk/jre/lib/rt.jar]
[Loaded java.net.InetAddress$1 from /usr/lib/jvm/java-7-openjdk/jre/lib/rt.jar]
[Loaded sun.awt.AppContext$PostShutdownEventRunnable from /usr/lib/jvm/java-7-openjdk/jre/lib/rt.jar]
[Loaded sun.awt.AWTAutoShutdown$1 from /usr/lib/jvm/java-7-openjdk/jre/lib/rt.jar]

wait about fifteen to twenty seconds, and it loads.

I have googled around a bunch and found nothing. I have asked people I know and found nothing. I wondered if anyone else had ever heard about this? If they had ever had this problem? Much appreciated.

Thanks,
--Scott

marcelomorales

Member

Registered: 2013-03-03

Posts: 4

Re: Java GUI applications always hang when connected to the network

Looks like a DNS problem. While you run the java application. try to do something like `sudo tcpdump -n -i wlan0 udp port 53` to see what dns lookups get made. Post the results and we'll see it from there.