Hello, I was wondering about the memory indications displayed at boot time. For example:
# dmesg| grep memory real memory = 51539607552 (49152 MB) avail memory = 49663688704 (47362 MB) The "real memory" is the size of the RAM modules in this computer (48 Gb). What's "avail memory"? The memory left after loading the kernel and its data structures? # sysctl -a | grep -i "hw.[a-z]*mem" hw.physmem: 51469168640 hw.usermem: 48338657280 hw.realmem: 53418655744 How come "physmem" be lower and "realmem" be higher than "real memory"? As an exercise, i've been unable to malloc more than 38 Gb of memory, despite having at least 43 Gb free at the time: # sysctl -a | egrep "vm.stats.vm.v_(free_count|inactive_count|cache_count|page_size)" vm.stats.vm.v_cache_count: 19 vm.stats.vm.v_inactive_count: 2113 vm.stats.vm.v_free_count: 11414720 vm.stats.vm.v_page_size: 4096 # sysctl kern.maxdsiz kern.maxdsiz: 51539607552 # mdconfig -a -t malloc -o reserve -s 38g md0 # mdconfig -d -u 0 # mdconfig -a -t malloc -o reserve -s 39g mdconfig: ioctl(/dev/mdctl): Cannot allocate memory Just for the sake of curiosity, any idea about why? Best regards, Hubert -- View this message in context: http://old.nabble.com/phys-vs-real-vs-user-%28avail%29-memory--tp28505453p28505453.html Sent from the freebsd-questions mailing list archive at Nabble.com. _______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
