The answer I expected is the JVM grows as much as to the available system memory of there are m min and max set.
-Gokul Sent from iPhone > On Feb 22, 2016, at 2:43 AM, André Warnier (tomcat) <a...@ice-sa.com> wrote: > >> On 22.02.2016 03:44, Gokul.Baskaran wrote: >> Thanks again, to make things clear. When I meant default, what is the >> default min and max that is given to an application if there nothing defined >> in the JVM ? > > In how many different ways do you need to be told this ? > Re-read the previous answers that you already received. All the information > is there. > >> In my case, the Tomcat is running on windows and I don't have setenv.bat or >> sentenv.sh or even catalina.bat and catalina.conf does not have the OPT >> config for min and max. HTH >> >> Thank you >> >> -Gokul >> >> >> -----Original Message----- >> From: Olaf Kock [mailto:tom...@olafkock.de] >> Sent: Sunday, February 21, 2016 3:04 PM >> To: Tomcat Users List <users@tomcat.apache.org> >> Subject: Re: Tomcat memory >> >> grep mx bin/* found only settings in setenv.sh in my installation - this >> lets me state that there are no defaults: setenv.sh is not contained in the >> distribution but will be read in case it's found in the file system. >> Thus there's no tomcat default that I'm aware of. Anybody who distributes >> tomcat with a setenv.sh might have a sensible default for their embedded >> application, but the raw distribution AFAIK has none. >> >> Safe assumption should be: Whatever the JVM thinks is appropriate is the >> default. >> >> Create a setenv.sh or setenv.bat and set CATALINA_OPTS to the desired value, >> e.g. "-Xms 2048m -Xmx2048m" (but there will probably be more settings, e.g. >> for tuning the garbage collector... >> >> (apologies in case this goes out after the problem has long been solved: >> I'm in a hotel that blocks SMTP and have to find a way to send mail from >> here) >> >> Olaf >> >>> Am 21.02.2016 um 18:23 schrieb Gokul.Baskaran: >>> Question was for Java 7 >>> >>> It is a Tomcat / Application question as well, as memory default can be >>> configured in the application config. >>> >>> I totally agree that the best practice is to set the Xms and -Xmx. As am >>> going to change the config, I would curious to know if the tomcat ui or the >>> catalina does not have a Xms and -Xmx, would it default to 400MB? I read >>> this in another forum. >>> >>> -Gokul >>> >>> >>> -----Original Message----- >>> From: Olaf Kock [mailto:tom...@olafkock.de] >>> Sent: Sunday, February 21, 2016 3:14 AM >>> To: Tomcat Users List <users@tomcat.apache.org> >>> Subject: Re: Tomcat memory >>> >>> This is rather a Java than a tomcat question: >>> >>> The JVM allocates memory based on whatever default your current JVM >>> version decides (you don't mention what version of Java you're on) >>> >>> From a text on >>> http://docs.oracle.com/javase/7/docs/technotes/guides/vm/gc-ergonomics >>> .html >>> that's linked from my Java's manpage: >>> >>> *initial heap size* >>> >>> Larger of 1/64th of the machine's physical memory on the machine >>> or some reasonable minimum. Before J2SE 5.0, the default initial >>> heap size was a reasonable minimum, which varies by platform. >>> You can override this default using the |-Xms| command-line option. >>> >>> *maximum heap size* >>> >>> Smaller of 1/4th of the physical memory or 1GB. Before J2SE 5.0, >>> the default maximum heap size was 64MB. You can override this >>> default using the |-Xmx| command-line option. >>> >>> *Note:* The boundaries and fractions given for the heap size are >>> correct for J2SE 5.0. They are likely to be different in subsequent >>> releases as computers get more powerful. >>> >>> Note that this is from JavaSE7 and even mentions 5 - with more power there >>> comes more initial and maximum memory defaults. >>> >>> I'm not aware of the actual development of the default memory - mostly >>> because I consider it good practice to know what an application uses >>> and provide it explicitly, rather than relying on defaults. (and >>> frankly, on the applications that I see, the default typically is not >>> even enough - let alone a good basis for tuning) >>> >>> While we're at it: For production systems I consider it good practice to >>> set -Xms and -Xmx to the same value. Reason: If you don't have enough >>> memory available, you want to know this when the process starts, not days >>> later when it tries to allocate "the rest" - typically sunday night at 3am. >>> >>> Olaf >>> >>>> Am 21.02.2016 um 03:39 schrieb Gokul.Baskaran: >>>> Hi, >>>> >>>> I am currently running tomcat 7 in Windows 2012. >>>> >>>> The current JVM Heap memory parameters are set to empty, does the JVM Heap >>>> memory utilize the entire memory of the OS or does it default to a >>>> specific memory number? >>>> >>>> Thank you >>>> -Gokul >>> >>> --------------------------------------------------------------------- >>> 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 > > --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
