24 hours java loop - resources leak?

[G Svensson]

Hi,

We are in a situation at work where we need to get away from having jobs executing on timer since there can be overlaps. We need to move towards having jobs executing based on events like if files exists in a given catalog.

Is it advisable to let a java loop run 24 hours a day - checking every 5 minutes if there exist files in a given catalog and only then do an external call to the actual job? In my opinion a loop using Thread.sleep(5*60*1000) is returning resources to the operating system (Idle process). Is this true or false?

I am constantly beeing questioned at work by a colleague. He always tells me that java is no good since it consumes so much memory and resources.
Please give me a web URL (or arguments) that explains to him that small java applications are not more harmful than batch files or shell scripts. Both can of course contain bugs but java is not bound to clay down our servers.

Cheers,

Mr G

[Vinoth Kumar Kannan]

java.util.Timer and java.util.TimerTask classes can help you set timers in java. With this, you can schedule a particular part of your code to be executed in specific intervals.
I would consider this better than sleeping & waking inside a loop.

[Karthik Shiraly]

In such a situation, I'd have used cron or scheduled task (depending on the OS) for scheduling, and made it execute a java class only if shell script couldn't do the job.
As much as I'd like to bat for java, I agree with your colleague - JVMs occupy a little too much system memory; even the low signature ones like JRockit. Sometimes, this is acceptable; sometimes it's not.

[G Svensson]

I understand. Thanks.

So what about the last part:

I am constantly beeing questioned at work by a colleague. He always tells me that java is no good since it consumes so much memory and resources.
Please give me a web URL (or arguments) that explains to him that small java applications are not more harmful than batch files or shell scripts. Both can of course contain bugs but java is not bound to clay down our servers.

 

[G Svensson]

 

Karthik Shiraly wrote:JVMs occupy a little too much system memory; even the low signature ones like JRockit. Sometimes, this is acceptable; sometimes it's not.

So is it better to move to Scala? It uses jvm as well but occupies not so much system memory.

Cheers,
G

[fred rosenberger]

 

G Svensson wrote:I am constantly beeing questioned at work by a colleague. He always tells me that java is no good since it consumes so much memory and resources.
Please give me a web URL (or arguments) that explains to him that small java applications are not more harmful than batch files or shell scripts. Both can of course contain bugs but java is not bound to clay down our servers.

Turn it around. Ask him to provide a document or web URL that shows that java DOES use so much more memory and resources (and make sure it is a recent article).

[G Svensson]

 

Turn it around. Ask him to provide a document or web URL that shows that java DOES use so much more memory and resources (and make sure it is a recent article).

I will do that. Thank you all for your answers and efforts.
cheers,
G Svensson

[Pat Farrell]

 

fred rosenberger wrote: Ask him to provide a document or web URL that shows that java DOES use so much more memory and resources (and make sure it is a recent article).

Especially the "recent" part.

When I first started writing Java code, a typical PC would have 64MB of ram. It wasn't until about 2000 that I had one with 256MB of RAM. These days, even a toy PC has one GB of ram, and all of the new ones I buy have 6 or 8 GB. Memory is essentially free. Its silly to argue over small differences. Changes of 4GB are meaningful, less is noise.