Apheus
Guru
Joined: 12 Jul 2008
Posts: 422
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 Posted: Sat May 07, 2011 1:33 pm Post subject: VM dirty ratio values from sysctl.conf not being set |
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Hi all,
I try to set background_ratio for the vm subsystem via /etc/sysctl.conf. I want to try if this makes the system more responsive on high IO load, after I have read this: https://forums.gentoo.org/viewtopic-t-876543.html#6676119.
However, on reboot the dirty_ratio is at the default value (10) again. I have the following in /etc/sysctl.conf:
| Code: | # /etc/sysctl.conf
#
# For more information on how this file works, please see
# the manpages sysctl(8) and sysctl.conf(5).
#
# In order for this file to work properly, you must first
# enable 'Sysctl support' in the kernel.
#
# Look in /proc/sys/ for all the things you can setup.
#
# Disables packet forwarding
#net.ipv4.ip_forward = 0
# Disables IP dynaddr
#net.ipv4.ip_dynaddr = 0
# Disable ECN
#net.ipv4.tcp_ecn = 0
# Enables source route verification
net.ipv4.conf.default.rp_filter = 1
# Enable reverse path
net.ipv4.conf.all.rp_filter = 1
# Enable SYN cookies (yum!)
# http://cr.yp.to/syncookies.html
#net.ipv4.tcp_syncookies = 1
# Disable source route
#net.ipv4.conf.all.accept_source_route = 0
#net.ipv4.conf.default.accept_source_route = 0
# Disable redirects
#net.ipv4.conf.all.accept_redirects = 0
#net.ipv4.conf.default.accept_redirects = 0
# Disable secure redirects
#net.ipv4.conf.all.secure_redirects = 0
#net.ipv4.conf.default.secure_redirects = 0
# Ignore ICMP broadcasts
#net.ipv4.icmp_echo_ignore_broadcasts = 1
# Disable TCP timestamping
net.ipv4.tcp_timestamps = 0
# Disables the magic-sysrq key
#kernel.sysrq = 0
# When the kernel panics, automatically reboot in 3 seconds
#kernel.panic = 3
# Allow for more PIDs (cool factor!); may break some programs
#kernel.pid_max = 999999
# You should compile nfsd into the kernel or add it
# to modules.autoload for this to work properly
# TCP Port for lock manager
#fs.nfs.nlm_tcpport = 0
# UDP Port for lock manager
#fs.nfs.nlm_udpport = 0
# swappiness
vm.swappiness = 0
# drop dirty ratio, for responsiveness on high io load
vm.dirty_ratio = 1
vm.dirty_background_ratio = 1
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tcp_timestamps and swappiness are being set correctly, but not dirty_ratio and dirty_background_ratio.
I have found some hints to similar problems, which seem to exist due to a race condition between various services/start scripts/modules being loaded:
http://comments.gmane.org/gmane.linux.slackware.armedslack/832
http://linux.derkeiler.com/Newsgroups/comp.os.linux.networking/2004-10/1016.html
Where would I have to set the ratio values, or where should I put a "sysctl -p" if this is the only way?
Thank you. |
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Kernel & Hardware
