Hi Chris, ah.. yes. You are right, I overlooked the available 16 GB Ram. Long time ago, when I used a physical server with 16 GB but in cloud environment, ram is money.
Greetings, Thomas -----Ursprüngliche Nachricht----- Von: Christopher Schultz <ch...@christopherschultz.net> Gesendet: Donnerstag, 20. Januar 2022 13:01 An: users@tomcat.apache.org Betreff: Re: AW: Tomcat dedicated server Thomas, On 1/20/22 04:16, Thomas Hoffmann (Speed4Trade GmbH) wrote: > just one remark: Take care about the 32 GB. Configuring more than 32 GB, the > Java Pointers will use 64 Bit and thus need double the space. > Thus 34 GB memory can be worse than 31 GB. > See also > https://blog.codecentric.de/en/2014/02/35gb-heap-less-32gb-java-jvm-me > mory-oddities/ > > Just my 2 cents. While this is indeed true (and can be surprising), it is not relevant. Nobody with 16GiB of physical memory has any business attempting to use a 32GiB heap. -chris > -----Ursprüngliche Nachricht----- > Von: Olaf Kock <tom...@olafkock.de> > Gesendet: Donnerstag, 20. Januar 2022 09:54 > An: users@tomcat.apache.org > Betreff: Re: Tomcat dedicated server > > Hi Lance > > On 19.01.22 23:35, Campbell, Lance wrote: >> On a Tomcat 9.x dedicated Linux server with 16G of memory, how much memory >> would you allocate for the OS? >> >> Assume there is no file processing taking place. Also assume Tomcat is >> communicating primarily with a PostgreSQL database and Apache web server >> each running on their own dedicated servers. The Tomcat application server >> is the only thing running on the Linux server. > > It depends (TM) > > Without knowing your application, the load (e.g. number of concurrent > users) and general setup, there's no way to tell. I'd rather handle > the question the other way around: How much memory does (your > application > on) Tomcat require. Tomcat itself is happy with just a little bit of memory, > but applications vary widely. Also, some applications are memory-bound, some > are I/O-bound, some are CPU-bound. So memory might not be your bottleneck to > worry about. > > You should load-test your application with a realistic load (plus > margin) and keep an eye on memory consumption. But in the end you'll find out > what is the first bottleneck to appear. It might not be memory. > > But to come back closer to your original question: I recommend to > deactivate swapspace for production servers, and configure -Xms equal > to -Xmx, so that you find shortages of memory early (when you start > the > application) rather than Sunday night at 3am. You might want to leave > 1-2G for the OS and start testing this way, or rather test how little > memory your app requires to run and add margin. My rule of thumb is: > The more memory there is to be claimed in GC, the longer a full GC run > takes. Often, many short but frequent GC runs are preferable to fewer > but longer lasting. (I didn't check if this still applies to the newer > generation of garbage collectors, so take this GC-statement with a > grain of salt) > > Olaf > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org > --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
