tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Robinson, Eric" <>
Subject RE: Setting the Right Amount of Memory
Date Sun, 20 Jun 2010 00:27:59 GMT
> Just a note here : 160 X 512 MB = 81 GB. If each Tomcat's 
> JVM Is allowed to use up to 512 MB of Heap, there might be 
> moments where a lot of JVM's will be using close to that 
> amount.  Unless your system can really support that amount 
> of real RAM, you may be in for massive swapping.

Thanks, but no worries there. I would never allow swapping. If I have to
allocate 512MB RAM to each instance, it will be on a new server with
adequate physical RAM.

> During a full GC, the JVM does nothing else (applications are
> frozen). So there may be an impact on the user experience during 
> that time.

That's the effect I'm trying to anticipate.

> Note also that the 81 GB above count only the Tomcat Heaps, and 
> disregard any other memory needed by your 160 instances.

Very good point.

Eric Robinson

Disclaimer - June 19, 2010 
This email and any files transmitted with it are confidential and intended solely for Tomcat
Users List. If you are not the named addressee you should not disseminate, distribute, copy
or alter this email. Any views or opinions presented in this email are solely those of the
author and might not represent those of . Warning: Although  has taken reasonable precautions
to ensure no viruses are present in this email, the company cannot accept responsibility for
any loss or damage arising from the use of this email or attachments. 
This disclaimer was added by Policy Patrol:

To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message