I have two sets of questions relating to user limit "memlock" in limits.conf on Linux
1)
What does the user limit "memlock" in limits.conf signify-
- is it the memory that is locked for the user as a whole
- is it the memory that is locked for each process by that user
For example, oracle user on a server is running 4 databases with SGA of 5GB each. Total SGA size 4*5=20GB and the hugepage size is also set to 20GB.
In this case, should the memlock be set to 5GB or 20GB?
I am aware of the MOS notes suggesting to set memlock to slightly lower than physical RAM, but here I want to understand the meaning/implication of setting memlock rather than just going ahead and setting it as per suggestion in MOS notes.
2)
Is memlock required to be set if we are not using hugepages?
If it is required to be set, should it be 5GB or 20GB (considering the example in 1 above)?
Thanks,
Amol.