Re: How to make the each looping concurrent thread to improve WHILE-loop performance?

From:

Patricia Shanahan <pats@acm.org>

Newsgroups:

comp.lang.java.programmer

Date:

Thu, 01 Feb 2007 13:55:23 GMT

Message-ID:

<fjmwh.17783$yx6.12007@newsread2.news.pas.earthlink.net>

www wrote:

Hi,

I have a while-loop which loops 360 times. Each looping takes 100ms, so
in total it takes 36 seconds, which is very long.

while(true) //looping 360 times
{
....//code for preparation of the method calling in the end

doIt(); //this method takes time. It inserts data into database
}

Right now, the flow is:

first looping -> second looping -> ..... -> 360th looping

I am wondering if I can make the loopings more or less concurrent so no
need for next looping to wait for the previous looping ends:

first looping ->
second looping ->
...
360th looping ->

Could you please give me some help? Thank you.

Is most of doIt's time spent waiting for the database insert? If so,
there may be potential, depending on the capabilities of the database.

You will need to use multiple threads to run the doIt calls. At the
other extreme from using a single thread to do all the calls, you could
start a new thread for each call. However, that will probably involve
more thread start overhead than is needed.

I think you will get better control over resources if you use the new
java.util.Concurrent features. See the API documentation introduction to
java.util.ThreadPoolExecutor.

Patricia