To determine the maximum size of a shared memory segment, run:
\n# cat \/proc\/sys\/kernel\/shmmax
\n2147483648
\nThe default shared memory limit for SHMMAX can be changed in the proc file system without reboot:
\n# echo 2147483648 > \/proc\/sys\/kernel\/shmmax
\nAlternatively, you can use sysctl(8) to change it:
\n# sysctl -w kernel.shmmax=2147483648
\nTo make a change permanent, add the following line to the file \/etc\/sysctl.conf (your setting may vary).
\nThis file is used during the boot process.
\n# echo “kernel.shmmax=2147483648” >> \/etc\/sysctl.conf
\nWe also got this:
\nChecking kernel
\n222\/433
\nparameters
\nChecking for
\nsemmsl=250; found semmsl=250. Passed
\nChecking for
\nsemmns=32000; found semmns=32000. Passed
\nChecking for
\nsemopm=100; found semopm=32. Failed
\n<<<<
\nChecking for
\nsemmni=128; found semmni=128. Passed
\nChecking for
\nshmmax=536870912; found shmmax=33554432. Failed
\n<<<<
\nChecking for
\nshmmni=4096; found shmmni=4096. Passed
\nChecking for
\nshmall=2097152; found shmall=2097152. Passed
\nChecking for
\nfile-max=65536; found file-max=751357. Passed
\nChecking for
\nVERSION=2.6.9; found VERSION=2.6.9-55.0.0.0.2.ELlargesmp.
\nPassed
\nChecking for
\nip_local_port_range=1024 – 65000; found ip_local_port_range=32768
\n– 61000. Failed
\n<<<<
\nChecking for
\nrmem_default=262144; found rmem_default=135168. Failed
\n<<<<
\nChecking for
\nrmem_max=262144; found rmem_max=135168. Failed
\n<<<<
\nChecking for
\nwmem_default=262144; found wmem_default=135168. Failed
\n<<<<
\nChecking for
\nwmem_max=262144; found wmem_max=135168. Failed
\n<<<<
\nCheck complete. The
\noverall result of this check is: Failed
\n<<<<
\nProblem: The kernel
\nparameters do not meet the minimum requirements (see
\nabove).
\nRecommendation: Perform
\noperating system specific instructions to update the kernel
\nparameters.
\n223\/433
\nso for semopm we do a:
\n[root@irwdbd1 ~]# ipcs -ls
\n—— Semaphore Limits ——–
\nmax number of arrays = 128
\nmax semaphores per array = 250
\nmax semaphores system wide = 32000
\nmax ops per semop call = 32
\nsemaphore max value = 32767
\nand set it to be changed on reboot as:
\n[root@server ~]# echo “kernel.sem=250 32000 100 128” >> \/etc\/sysctl.conf
\nset it also live as:
\n[root@server ~]# echo “250 32000 100 128” > \/proc\/sys\/kernel\/sem
\nFor the rest, i just added these lines to \/etc\/sysctl.conf:
\nnet.ipv4.ip_local_port_range = 1024 65000
\nnet.core.rmem_default=262144
\nnet.core.wmem_default=262144
\nnet.core.rmem_max=262144
\nnet.core.wmem_max=262144
\nand ran a
\n[root@server ~]# \/sbin\/sysctl -p
\nnet.ipv4.ip_forward = 0
\nnet.ipv4.conf.default.rp_filter = 1
\nnet.ipv4.conf.default.accept_source_route = 0
\nkernel.sysrq = 0
\nkernel.core_uses_pid = 1
\nkernel.sem = 250 32000 100 128
\n224\/433
\nkernel.shmmax = 536870912
\nnet.ipv4.ip_local_port_range = 1024 65000
\nnet.core.rmem_default = 262144
\nnet.core.wmem_default = 262144
\nnet.core.rmem_max = 262144
\nnet.core.wmem_max = 262144
\nYou can also run these commands to get the variables oracle recommends to tune:
\nsysctl -a | grep -i shmmni
\nsysctl -a | grep -i ‘kernel.sem’
\nsysctl -a | grep -i ip_local_port_range
\nsysctl -a | grep -i rmem_default
\nsysctl -a | grep -i rmem_max
\nsysctl -a | grep -i wmem_default
\nsysctl -a | grep -i wmem_max
\nsysctl -a | grep -i shmmax
\nYou will get something like:
\nkernel.shmmni = 4096
\nkernel.sem = 250 32000 100 128
\nnet.ipv4.ip_local_port_range = 1024 65000
\nnet.core.rmem_default = 262144
\nnet.core.rmem_max = 262144
\nnet.core.wmem_default = 262144
\nnet.core.wmem_max = 262144
\nkernel.shmmax = 2147483648
\n225\/433<\/p>\n","protected":false},"excerpt":{"rendered":"
To determine the maximum size of a shared memory segment, run: # cat \/proc\/sys\/kernel\/shmmax 2147483648 The default shared memory limit for SHMMAX can be changed in the proc file system without reboot: # echo 2147483648 > \/proc\/sys\/kernel\/shmmax Alternatively, you can use sysctl(8) to change it: # sysctl -w kernel.shmmax=2147483648 To make a change permanent, add […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-438","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"\/blog\/index.php\/wp-json\/wp\/v2\/posts\/438","targetHints":{"allow":["GET"]}}],"collection":[{"href":"\/blog\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"\/blog\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"\/blog\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"\/blog\/index.php\/wp-json\/wp\/v2\/comments?post=438"}],"version-history":[{"count":0,"href":"\/blog\/index.php\/wp-json\/wp\/v2\/posts\/438\/revisions"}],"wp:attachment":[{"href":"\/blog\/index.php\/wp-json\/wp\/v2\/media?parent=438"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"\/blog\/index.php\/wp-json\/wp\/v2\/categories?post=438"},{"taxonomy":"post_tag","embeddable":true,"href":"\/blog\/index.php\/wp-json\/wp\/v2\/tags?post=438"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}