This is just a quick a note to show how we can monitor some important kernel parameters limits. This can be very handy in case of highly consolidated database environment where the default limits are usually not enough.
Semaphores (SEMMSL, SEMMNI, SEMMNS)
20 array out of 256 are used and 21 semaphore out of 32000 are used.
Maximum number of open file handles (fs.file-max)
3360 out of 6815744 are used .
Maximum number of current asynchronous I/O requests (fs.aio-max-nr)
0 out 1048576 slots are used .
Shared Memory (SHMMAX, SHMALL, SHMMNI)
1 segment out of 4096 is used and almost all the shared memory is free.
Hugepages configuration (vm.nr_hugepages)
That’s it 🙂 for guideline for setting the initial value for this parameters i invite you to check the following docs :
- https://access.redhat.com/documentation/en-us/reference_architectures/2017/html-single/deploying_oracle_rac_database_12c_release_2_on_red_hat_enterprise_linux_7/index
- What value should kernel parameter AIO-MAX-NR be set to ? (Doc ID 2229798.1)
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