Updated 10-19-2008

Slow internet speed for Mandriva 2009.0 2008.1 2008.0

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This could be a major speed problem if you just installed mandriva 2008.0 or 2008.1 or 2009.0 and you are using a router that is running ipv4. Mandriva default on 2008.0, 2008.1, and 2009.0 is defaulted as ipv6. In that case you probably need to modify the following files for faster Internet surfing. Modification of these files will at least double your Internet speed, unless you are using a ipv6 router.

Slow internet response (particularly web browsing)

See also Bug #27070. There is a known problem with all Linux distributions that enable IPv6 networking (the new standard for network addresses which uses a longer, hexadecimal address format to provide a much larger number of possible addresses. The old standard is IPv4, which gives the four-groups-of-three-digits decimal address format most people are familiar with, e.g. 216.105.167.65). Some systems and networks do not cope well if your system has IPv6 networking enabled. If you experience sluggish response on the Internet – especially when browsing web sites – and cannot find the cause, you should try disabling IPv6. To do this, edit the file /etc/modprobe.conf, add the following line, and reboot:

install ipv6 /bin/true

See also
Bug #27073.
If this does not resolve the problem, there is another possibility.
Most Linux distributions, including Mandriva, enable a kernel feature
called TCP window scaling. This is useful for increasing the speed of
transfers over very high bandwidth connections. However, a change was
made in the default values for TCP window scaling in kernel 2.6.17,
which seems to cause very slow network performance for some users
with some internet sites. To see if TCP window scaling is the
problem, you can disable it with this command:

sysct1
-w net.ipv4.tcp_window_scaling=0

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