# VM dirty ratio values from sysctl.conf not being set

## Apheus

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:

```
# /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

```

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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