1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Has anyone calculated how much memory...

Discussion in 'Tomato Firmware' started by Kiwi8, Jan 20, 2008.

  1. Kiwi8

    Kiwi8 LI Guru Member

    ... is taken by a single connection in the Conntrack table? How much memory will 4096 entries take up in total?
     
  2. szfong

    szfong Network Guru Member

    368 bytes per conntrack --> 1472KBytes
     
  3. Kiwi8

    Kiwi8 LI Guru Member

    Thanks. I have since got back to checking the code and it is as u said. That means with a typical free 7MB when the router is in usage, a table of 4096 entries is more than enough for the router to handle?
     
  4. szfong

    szfong Network Guru Member

    Actually you WILL NOT reach near 4096 conn track before your router's cpu becomes unusable. Depending on what you do, eg, if your blasting away on bittorrent and opening up about 1500 conn tracked will pretty much saturate the cpu, even on a 6Mbps cable connection. On a FIOS connection a couple dozen connections doing high speed transfers will saturate the cpu. The higher your speed, the less # of "simultaneous" connected connections it takes to saturate the router's cpu. When the NAT table gets large, it will cause the router to slow down even further.
     
  5. Kiwi8

    Kiwi8 LI Guru Member

    So your suggestion is to set the maximum number of connections to be its default value 2048?
     
  6. M_ars

    M_ars LI Guru Member

    yes 2048 is just perfect. 4096 is too much. You can easily test that with Steam (Valve HL2). If you let the server-browser refesh too long, the router reboots...
     
  7. szfong

    szfong Network Guru Member

    2048 is plenty, all the default timeouts are good, in my opinion. if your connection count goes up check cpu usage, if it's (cpu usage is relatively) low, you may increase the # of conn. if it's reaching max usage, try lowering timouts, it's less cpu cpu intensive that way. Also, the max # is 10240, I believe, but I leave it at 2048, just to keep cpu usage in check.
     
  8. Kiwi8

    Kiwi8 LI Guru Member

    Thanks for the information everyone.

    I have since left it alone and instead tweaked the timeout to be 1800 seconds (30 mins).
     

Share This Page