CPU goes to 100%

["Murthy, Anand" <An...@tfn.com>]

Hi,

We have a big application using Tomcat v3.2.1 and we are doing alot of
Database connections.  It is running on Windows 2000 server and we are using
Sun's Java 1.3.  Most of the day the CPU stays at 0%, but for some reason
every afternoon it goes to 100% and application slows down to a crawl.  At
the end of each jsp file, we do some garbage collection, but it still does
not seem to help.

Does anyone have any ideas?

Thank you,

Anand Murthy
Jr. Software Engineer
Thomson Financial Research
617-856-1795

RE: CPU goes to 100%

[Victor Martinez <vi...@ariceta.com>]

> We have a big application using Tomcat v3.2.1 and we are doing alot of
> Database connections.  It is running on Windows 2000 server and
> we are using
> Sun's Java 1.3.  Most of the day the CPU stays at 0%, but for some reason
> every afternoon it goes to 100% and application slows down to a crawl.  At
> the end of each jsp file, we do some garbage collection, but it still does
> not seem to help.
>
> Does anyone have any ideas?
We had the same problem. Tomcat died and httpd threads grew up to consume
all cpu time.

Check references to objects stored in user's session, and mainly db
connections. If there are cyclic references, garbage collector will not free
any memory.
Use some debug application such as JProbe or OptimiceIt to see number of
objects, memory, etc.

Dead Locks could be other problem  :(

Un saludo.

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Victor Martinez Conte (victor.martinez@ariceta.com)
Analista funcional

Ariceta & Asociados  http://www.ariceta.com
Grupo IT Deusto
Alberto Alcocer 24, 7ª Planta 28036 - Madrid
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