Understanding and using socket RTT

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi,

I am writing an application in kernel which needs to make decisions based on RTT of the socket open with another host. So, I was looking at TCP code to find out how can I get that information from it. Whatever little I have understood from the code, it looks like tcp_sock->srtt (smoothed round trip time) is the one I can more or less trust to be the current rtt of the socket and that this value is in jiffies. 

However I got confused due to the comment on its declaration.

u32     srtt;           /* smoothed round trip time << 3        */

Questions I have 
1) Does this mean that the value stored in this variable is already left shifted by 3 or it should be left shifted by 3 before using it ?
Or the value is simply the computed rtt in jiffies and it has no relation with the left shift operation ?

2) Is the SRTT correct value to look at for rtt or should another metric / value be used for this?


Regards,
Vikash Kumar
http://VikashKumar.com/

_______________________________________________
Kernelnewbies mailing list
Kernelnewbies@xxxxxxxxxxxxxxxxx
http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies

[Index of Archives]     [Newbies FAQ]     [Linux Kernel Mentors]     [Linux Kernel Development]     [IETF Annouce]     [Git]     [Networking]     [Security]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux RAID]     [Linux SCSI]     [Linux ACPI]
  Powered by Linux