Optimizing Linux network TCP/IP kernel parameters

You can verify the Linux networking kernel parms from the root user with these commands::Many Oracle professionals do not note the required setting for optimizing Oracle*Net on Oracle 10g release 2.  Here is a review of the suggested TCP/IP buffer parameters:

$ sysctl –a|grep rmem

$ sysctl –a|grep wmem

The Linux networking kernel parms files are located:

/proc/sys/net/core

rmem_default

wmem_max

rmem_max      

wmem_default

 

/proc/sys/net/ipv4

tcp_rmem

tcp_wmem

The Linux networking kernel settings for 10gR2 are:

rmem_default	262144	/proc/sys/net/core/rmem_default
rmem_max	262144	/proc/sys/net/core/rmem_max
wmem_default	262144	/proc/sys/net/core/wmem_default
wmem_max	262144	/proc/sys/net/core/wmem_max
tcp_rmem	4096 87380 8388608	/proc/sys/net/ipv4/tcp_rmem
tcp_wmem	4096 65536 8388608	/proc/sys/net/ipv4/tcp_wmem
tcp_mem	4096 4096 4096	/proc/sys/net/ipv4/tcp_mem

Setting /etc/sysctl.conf

You can enter them in sysctl.conf in /etc to have them persist through shutdowns. For setting the live values use sysctl –w  from the root user.

$ sysctl –w net.core.rmem_default=262144  <== no spaces

For multiple value entries:

$ sysctl –w net.ipv4.tcp_rmem="4096 87380 8388608"

In sysctl.conf:

net.core.rmem_default = 262144 <== has spaces

net.ipv4.tcp_rmem = 4096 87380 8388608