Re: What is the timeout of TCP in freeBSD?

2013-01-20 Thread Karthik Reddy
When I change the kern.hz to 50, the timeout is happening at 76sec. Could
you please elaborate on kern.hz and how does it effect timing.


On Sun, Jan 20, 2013 at 10:12 PM, Adam Vande More wrote:

> On Sun, Jan 20, 2013 at 8:50 AM, Karthik Reddy 
> <22karthikre...@gmail.com>wrote:
>
>> I was doing a experiment on FreeBSD for testing TCP timeout and RTO. OS is
>> being run from two different VMware versions 4.0 and 5.0.
>>
>> Present Scenario: VMware Player 4.0
>> I'll start a telnet session to a non-existing system in the network. When
>> I
>> look at the tcpdump the RTO starts at every 3 seconds and after some
>> exponential backoff starts. In this scenario after 75 seconds the TCP
>> gives
>> up and tells me that there is no system existing with the IP and telnet
>> session terminates.
>>
>> Next Scenario: VMware Player 5.0
>> In this scenario, I did the same but the RTO starts at 5 sec and then
>> varies. In this scenario, it takes more than 120 seconds for telnet
>> session
>> to tell me that there is no system is available in the network.
>>
>> I have seen sysctl in both VM's. net.inet.tcp.keepinit = 75000
>>
>> Is this problem something related to timing of the VM's or any other
>> issue?
>>
>
> What's the wallclock delta during such a test?  Have you tried setting
> 'kern.hz="50"' or fiddling other TC options?  UP VM's tend to keep time
> better than other multicore configs.
>
> --
> Adam Vande More




-- 
Karthik Reddy
I'm not the best, but I'm not like the Rest
___
freebsd-questions@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-questions
To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"


What is the timeout of TCP in freeBSD?

2013-01-20 Thread Karthik Reddy
I was doing a experiment on FreeBSD for testing TCP timeout and RTO. OS is
being run from two different VMware versions 4.0 and 5.0.

Present Scenario: VMware Player 4.0
I'll start a telnet session to a non-existing system in the network. When I
look at the tcpdump the RTO starts at every 3 seconds and after some
exponential backoff starts. In this scenario after 75 seconds the TCP gives
up and tells me that there is no system existing with the IP and telnet
session terminates.

Next Scenario: VMware Player 5.0
In this scenario, I did the same but the RTO starts at 5 sec and then
varies. In this scenario, it takes more than 120 seconds for telnet session
to tell me that there is no system is available in the network.

I have seen sysctl in both VM's. net.inet.tcp.keepinit = 75000

Is this problem something related to timing of the VM's or any other issue?

-- 
Karthik Reddy
I'm not the best, but I'm not like the Rest
___
freebsd-questions@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-questions
To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"