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<!doctype linuxdoc system>
<title>RTACCT Utility
<author>Robert Olsson
<date>some_negative_number, 20 Dec 2001
Here is some code for monitoring the route cache. For systems handling high
network load, servers, routers, firewalls etc the route cache and its garbage
collection is crucial. Linux has a solid implementation.
The kernel patch (not required since linux-2.4.7) adds statistics counters
from route cache process into
/proc/net/rt_cache_stat. A companion user mode program presents the statistics
in a vmstat or iostat manner. The ratio between cache hits and misses gives
the flow length.
Hopefully it can help understanding performance and DoS and other related
<p> An URL where newer versions of this utility can be (probably) found
<p>The format of the command is:
rtstat [ OPTIONS ]
<p> <tt/OPTIONS/ are:
<item><tt/-h/, <tt/-help/ - show help page and version of the utility.
<item><tt/-i INTERVAL/ - interval between snapshots, default value is
2 seconds.
<item><tt/-s NUMBER/ - whether to print header line. 0 inhibits header line,
1 prescribes to print it once and 2 (this is default setting) forces header
line each 20 lines.