I'm trying to set up a tomcat server to make use of my machine's 6 gig worth of memmory (it needs it). However when i try to set the -Xmx option to set a maximum heap size over 1800m then i get an error saying "could not reserve enough space for object heap" . This behavior is the same with sun's j2sdk1.4.1_02, blackdowns j2sdk1.4.1-01 and bea's jrockit 8. Does anyone know if heap size can get beyond 1.8 gig on linux, and if so how to do it?
posted 12 years ago
To answer my own question looks like just below 2 gig is all the memmory the jvm can use on linux. see http://developer.java.sun.com/developer/bugParade/bugs/4435069.html Fo the lazy this says: "using Java on linux the maximum amount of memory you can use is -mx1960m, ie you cannot use a 2GB Java heap. Ie Java -mx2000m -version will display an error message about lack of heap space Part of the problem is that linux has previously had restrictions with pthreads using a 2GB heap even though the stack space per process is 'unlimited'" my research seems to indicate that the limit is 4gig on sparcs so even suns own hardware has a fairly low limit.