Shminfo_shmmax in /etc/system does not match project.max-shm-memory

Question

If I specified 'shminfo_shmmax' in /etc/system and hava the system default in /etc/project(no change is made), the size of 'project.max-shm-memory' is 10 times larger than 'shminfo_shmmax'.
#more /etc/system // (16MB)
set shmsys:shminfo_shmmax=16000000
#prctl -n "project.max-shm-memory" -i project user.root
=> will display like below.
project: 1: user.root
NAME PRIVILEGE VALUE FLAG ACTION RECIPIENT
project.max-shm-memory
privileged 1.49GB - deny -
system 16.0EB max deny
1.49GB is 10 times larger than 'SHMMAX'. If I add more entries /etc/system like below, max_shm_memory will become even larger.
#more /etc/system
set shmsys:shminfo_shmmax=16000000
set semsys:seminfo_semmni=2000
set shmsys:shminfo_shmmni=2000
set msgsys:msginfo_msgmni=2048
After I reboot with the above /etc/system and no change /etc/project(all default, no values added)
# prctl -n "project.max-shm-memory" -i project user.root
project: 1: user.root
NAME PRIVILEGE VALUE FLAG ACTION RECIPIENT
project.max-shm-memory
privileged 29.8GB - deny -
system 16.0EB max deny -
Can anyone shed light about this area how to configure SHMAX in /etc/system right?

Answer 1

We saw similar behavior and opened a case with Sun.
The problem turns out to be that the (deprecated) /etc/system to (new) project resource limits isn't always one-to-one.
For example process.max-shm-memory gets set to shmsys:shminfo_shmmax * shmsys:shminfo_shmmni.
The logic here is that under the /etc/system tunings you might have wanted the maximum number of segments of the maximum size so the system has to be able to handle that. Make sense to some degree. I think Sun updated one of their info docs on the process at the end of our case to make this clearer.