Win a copy of Java Database Connections & Transactions (e-book only) this week in the JDBC forum!
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Devaka Cooray
  • Knute Snortum
  • Paul Clapham
  • Tim Cooke
Sheriffs:
  • Liutauras Vilda
  • Jeanne Boyarsky
  • Bear Bibeault
Saloon Keepers:
  • Tim Moores
  • Stephan van Hulst
  • Ron McLeod
  • Piet Souris
  • Frits Walraven
Bartenders:
  • Ganesh Patekar
  • Tim Holloway
  • salvin francis

One Java program makes all java programs very slow  RSS feed

 
Rancher
Posts: 4686
7
Linux Mac OS X VI Editor
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
I'm running Snow Leopard on my quad core MBP. I am developing Java programs on it. I have the Sun Java JDK.

java version "1.6.0_26"
Java(TM) SE Runtime Environment (build 1.6.0_26-b03-384-10M3425)
Java HotSpot(TM) 64-Bit Server VM (build 20.1-b02-384, mixed mode)

I'm seeing something on this OSX machine that I've never seen before. When I run a big, slow program, say one that processes a million big records, it can take a long time, several hours to run.

I find that while it is running, every other application that uses Java is also dog slow. Things like Vuze become so unresponsive as to be unusable.

It feels as if there is only one JVM on the box.

Top does not show more than one core being used heavily, and typically no Java process uses more than 50% of one core. Which makes sense, because the programs do a bit of java, then talk to MySql, then do a bit more, iterating back and forth.

Is this normal?
Is my guess (one JVM for the whole machine) likely? or correct?

Is there a way to run two JVMs at once? Its not as if there is anything in common between the code I write and the code in Vuze.
 
If tomatoes are a fruit, then ketchup must be a jam. Taste this tiny ad:
how do I do my own kindle-like thing - without amazon
https://coderanch.com/t/711421/engineering/kindle-amazon
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
Boost this thread!