tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Adrian Sutton <adr...@symphonious.net>
Subject Re: Very Slow Startup with APR
Date Tue, 21 Aug 2007 12:06:39 GMT
> I had just re-read Mladen's mail and experimented with RANDFILE  
> myself,
> thinking that setting it to /dev/urandom might be the easiest  
> solution.
> I strace'd Tomcat but couldn't find any hint that the value of  
> RANDFILE
> is honored. Since my APR is built to use /dev/urandom I can't be sure,
> but if you just restarted Tomcat doing some typing and mouse-moving in
> between, the speed increase during startup might just be a result of
> /dev/random having gathered enough entropy in the meantime to satisfy
> Tomcat's read request without blocking.

RANDFILE is definitely honored and it does work well setting it as / 
dev/urandom. I've restarted Tomcat a number of times and it stayed  
fast, plus:
cat /proc/sys/kernel/random/entropy_avail
consistently returns low values. Generating activity. In fact, with  
hindsight the times that Tomcat took longest to start were the times  
I wasn't doing anything else on the server - but the startup time was  
always 5 minutes or more and now it starts in under a minute. I'm  
only accessing the server via SSH btw - it's actually an Amazon EC2  
instance.

> Does Tomcat start still fast if you do something like
> dd if=/dev/random of=/dev/null bs=1
> let that run for a couple of seconds and start Tomcat immediately  
> after
> interrupting it?

Yep, no delays at all.

Adrian Sutton
http://www.symphonious.net

---------------------------------------------------------------------
To start a new topic, e-mail: users@tomcat.apache.org
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org


Mime
View raw message