Thanks Pete - good info. I'll file that away :) so each "address" is 64bits even if the storage is only 32bits. Weird but I think I got it.
I think 2 gigs for the OS is fine - at least on a windows box dedicated to CF the OS doesn't need much more than that typically even with some backup agents etc. I agree with you on the permsize though.... -mark -----Original Message----- From: Pete Freitag [mailto:p...@foundeo.com] Sent: Tuesday, September 03, 2013 11:41 AM To: cf-talk Subject: Re: Good jvm ram settings for 64 bit ColdFusion On Tue, Sep 3, 2013 at 9:08 AM, Mark A Kruger <mkru...@cfwebtools.com>wrote: > In 32 bit addressing each memory "address" takes up 4 bytes (4 x 8 bits) > but a 64 bit address space is wider (as in 8 x 8 bits). So for example, if > you store an integer - say 14 - on a 32 bit system, it will take 4 bytes to > do it (00000000 00000000 00000000 00001110). That is correct about the addressing being larger on 64 bit, but it still uses 32 bits to store an int (in Java at least, this may differ if you are doing c/c++, etc), but it's address is twice as big. So what accounts for the extra heap usage is that when you have an object reference (or a pointer) to another object or primitive within an object instead of taking 32 bits per reference it takes 64 bits. Also Michael - 2gb perm size seams rather large generally speaking (unless you have tons of cfm/cfc files). Further if your server has 8GB of ram, and you are setting 6GB max heap and 2GB max perm size then you are not leaving any room for the OS to operate when things get full. The perm size does not usually change much once the application is fully loaded and all possible logic routes have executed at least once (unless you have some sort of dynamic cfml generating going on) so you should be able to see how much you are actually using at runtime by running this code: http://www.petefreitag.com/item/821.cfm -- Pete Freitag - Adobe Community Professional http://foundeo.com/ - ColdFusion Consulting & Products http://hackmycf.com - Is your ColdFusion Server Secure? http://www.youtube.com/watch?v=ubESB87vl5U - FuseGuard your CFML in 10 minutes ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Order the Adobe Coldfusion Anthology now! http://www.amazon.com/Adobe-Coldfusion-Anthology/dp/1430272155/?tag=houseoffusion Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:356700 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/groups/cf-talk/unsubscribe.cfm
