Rick Noel
Systems Programmer | Westwood One
rn...@westwoodone.com

-----Original Message-----
From: Christopher Schultz <ch...@christopherschultz.net> 
Sent: Wednesday, March 27, 2024 8:24 AM
To: Tomcat Users List <users@tomcat.apache.org>; Rick Noel 
<rn...@westwoodone.com.INVALID>
Cc: Voodoo nmulcahy gmail <nmulc...@gmail.com>; David Jung 
<david.j...@cumulus.com>
Subject: [EXT]Re: performance tunning of Tomcat 10

Rick,

On 3/27/24 07:53, Rick Noel wrote:
> I was wondering if the apache foundation has any tools we can use to 
> fine tune Tomcat 10. Tools to deteming how to set the best heap size 
> for Tomcat startup and the best connection attributes of 
> minSpareThreads and MaxThreads.
What is your goal?
Our application is a sip phone call handling application.(A voice response xml 
application)
The goal is to not have  call bottleneck at peak call volume.
Sometimes too many folks call at one time hit our app and calls are not handle 
correctly.

> I know my application at times will reach 100 concurrent connections
 > and some times goes has high as 500 connections.

Okay.
Well I do not have actual traffic info down to the sec,
But from the application logs I know that that points in the day more than 300 
calls can come in

> Should I boost minSpareThreads and maxThread values of what I plan to 
> use below? > Or why would we not just set very high minSpareThreads 
> and maxThread values like minSpareThreads =300  and maxThread=1000
>
> This is a snippet of my server.xml
>
> <Executor  name="tomcatPhoneAppThreadPool"  namePrefix="catalina-executor-"
>                  minSpareThreads="50"
>                    maxThreads="300"    />
>
>        <Connector port="8585"
>                       executor="tomcatPhoneAppThreadPool"
>                       compression="on"
>                       compressionMinSize="2048"
>                       
> compressableMimeType="text/html,text/xml,text/plain,text/css,text/javascript,application/javascript,application/json,application/xml"
>                       protocol="org.apache.coyote.http11.Http11NioProtocol"
>                                     redirectPort="8443">
>                                         <UpgradeProtocol 
> className="org.apache.coyote.http2.Http2Protocol" />
>
>           </Connector>
>
> Also, am I good with setting  
> protocol="org.apache.coyote.http11.Http11NioProtocol"
> And then setting <UpgradeProtocol 
> className="org.apache.coyote.http2.Http2Protocol" />
>
> That will tell Tomcat to do HTTP2 Correct?

That's the only way to enable h2. Well... you could use Http11Nio2Protocol, 
too. NIO is the default protocol so you don't even need to add that 
specifically if you don't want to.

Back to threads.

Each thread (unless you go virtual, but that's not really production-ready IMHO 
at this point unless you have very strict circumstances where it will work 
great for you) takes up a bunch of memory, so you can't just set maxThreads=1M. 
Threads take "time" to start, but it's not really that much. If starting and 
stopping threads is what is making your application slow, than you have a very 
high-performance application and environment indeed.

Your question as stated is unanswerable.

You say you are sometimes hitting 500 connections. The default maximum number 
of connections is 10000 and you are only using 500. That means you aren't being 
flooded, which is a Good Thing. (BTW: How are you measuring "how many 
connections" you have? Make sure you are measuring the right thing...

I am estimating the actual connections just based on application call logs.

Is your *current* maxThreads set to 500? If so, then your thread pool maximum 
is set to your high-water mark which seems like it should be fine. If you set 
your maxThreads to 1000 you won't get any benefit because only 500 requests are 
ever being sent at once, right?

What else does your application do?
Our application is a sip phone call handling application.(A voice response xml 
application)

For example, if you have a thread-pool max-threads of 1000 and your application 
uses an RDBMS for every request but your db connection pool size is more like 
10, then many threads waiting on a small number of connections gets you 
absolutely no benefit. You'd have to make changes elsewhere in your application 
in order to make use of those extra threads.

Similarly, if you have a big thread pool and a big db connection pool, but your 
database performs slowly, then having all that power on the application server 
doesn't really help you.

Yes our app is using a database  (we use Postres)
And yes I assume that is our bottleneck
Our tomcat context.xml defines that database maxConnction to be only 
maxTotal="20"
We have other apps  and that hit this same database, so we define low maxTotal  
on each  server so each server can have only limit connection access to the 
database
I am thinkingit would be best to try and NOT optimize  minSpareThreads and 
maxThreads but instead to determine what is the optimal
Database  connection maxTotal to set

So anyone trying to answer "how big should be thread pool be" really needs to 
understand the nature of your application and the other things happening in 
your environment.

Sometimes the answer is "just add more threads/CPUs/memory" and sometimes the 
answer is "re-think your application architecture".

-chris

---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
For additional commands, e-mail: users-h...@tomcat.apache.org

CAUTION: This email originated from outside of the organization. Do not click 
links or open attachments unless you know the sender and you are sure the 
content is safe. Please report the message using the Report Message feature in 
your email client if you believe the email is suspicious.

Reply via email to