# shmall - maximum number of shared memory pages. If you set it to too low value can slowdown any program usng shared memory
# shmmax - maximum size of shared memory segment that can be allocated in the memory. For servers with lots of memory can be increased to 80% of memory to avoid shared memory fragmentation
# shmmni - maximum number of segments. It's good idea to change it only by vendor recommendation
kernel.shmall = 2097152
kernel.shmmax = 2147483648
kernel.shmmni = 4096
# semaphores: semmsl, semmns, semopm, semmni
# semmsl - maximum number of semaphores per semaphore identifier. Very big number will eat memory not used later
# semmns - maximum number of semaphores in the system. Size it carefully because of above reason
# semopm - Define maximum number of semaphore operations per system call
# semmni ¨C maximum number of semaphore identifier. Do not increase it over needed limit, because of waste of memory
kernel.sem = 250 32000 100 128
# the maximum number of file handles
fs.file-max = 65536
# ip_local_port_range - define full range of local ports in Linux, normally upper limit is 32000
# rmem_default - Default Receive Window
# rmem_max Maximum - Receive Window
# wmem_default - Default Send Window
# wmem_max - Maximum Send Window
net.ipv4.ip_local_port_range = 1024 65000
net.core.rmem_default = 1048576
net.core.rmem_max = 1048576
net.core.wmem_default = 262144
net.core.wmem_max = 262144
5. 为oracle用户提高shell限额,配置环境变量
To improve the performance of the software on Linux systems, you must increase the following shell limits for the oracle user:
nofile - Maximum number of open file descriptors
nproc - Maximum number of processes available to a single user
5.1 修改/etc/security/limits.conf 文件:
oracle soft nproc 2047
oracle hard nproc 16384
oracle soft nofile 1024
oracle hard nofile 65536
5.2 修改/etc/pam.d/login文件: