Shared Memory Limiits
Posted: Thu Feb 02, 2017 10:23 pm
Does hardware impose limits on the size of shared memory?
I am running a Dell E6330 i7 3rd Generation box with 8gb of ram. The system,, by default, configures 4 gb of shared memory.
7 cams run just fine under 720p resolution but when I bump em up to 1080p I end up with /dev/shm showing 100% used via df command and just one of the 7 cams fails. Converting that cam to 720p results all cams running fine. Nothing I do seems to change the maximum of 4gb shared memory via kernel shmmax and shmall parameters. I would think shared memory would be limited to less than or equal to ram and not 1/2 of ram. Am I running into a linux or hardware limitation here? Thx!
I am running a Dell E6330 i7 3rd Generation box with 8gb of ram. The system,, by default, configures 4 gb of shared memory.
7 cams run just fine under 720p resolution but when I bump em up to 1080p I end up with /dev/shm showing 100% used via df command and just one of the 7 cams fails. Converting that cam to 720p results all cams running fine. Nothing I do seems to change the maximum of 4gb shared memory via kernel shmmax and shmall parameters. I would think shared memory would be limited to less than or equal to ram and not 1/2 of ram. Am I running into a linux or hardware limitation here? Thx!
Code: Select all
Filesystem Size Used Avail Use% Mounted on
udev 3.9G 0 3.9G 0% /dev
tmpfs 787M 9.6M 778M 2% /run
/dev/mapper/ubuntu--vg-root 1.8T 1.5T 198G 89% /
tmpfs 3.9G 3.9G 0 100% /dev/shm
tmpfs 5.0M 4.0K 5.0M 1% /run/lock
tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup
/dev/sda1 472M 207M 242M 47% /boot
tmpfs 787M 28K 787M 1% /run/user/108
tmpfs 787M 0 787M 0% /run/user/1000