realtime for freeradius
With modern operating systems we have various server task scheduling options available to use. We can either use OSes modified to provide soft real-time such as versions of Linux. We can also ask the task schedulers to give certain processes either higher priority or to give them real-time alike scheduling, as is possible in Solaris and maybe Linux. I wonder of anyone has experimented with observing FreeRadius performance under load conditions with these options? We shouldn't expect faster performance, but we may achieve more consistent behaviour - for example a smaller variance in response times. Thoughts and suggestions welcome. tariq (this applies not just to freeradius but other server tasks too) - List info/subscribe/unsubscribe? See http://www.freeradius.org/list/users.html
Re: realtime for freeradius
On Wed 20 Sep 2006 14:09, Tariq Rashid wrote: With modern operating systems we have various server task scheduling options available to use. We can either use OSes modified to provide soft real-time such as versions of Linux. We can also ask the task schedulers to give certain processes either higher priority or to give them real-time alike scheduling, as is possible in Solaris and maybe Linux. I wonder of anyone has experimented with observing FreeRadius performance under load conditions with these options? We shouldn't expect faster performance, but we may achieve more consistent behaviour - for example a smaller variance in response times. Thoughts and suggestions welcome. Realtime typically is used for Telecom and Telemetry applications. I can't think of any reason why you would need a radius server to run as realtime however... Generally you are in any case waiting on a backend LDAP or SQL database in any case.. Cheers -- Peter Nixon http://www.peternixon.net/ PGP Key: http://www.peternixon.net/public.asc pgpElaJl7voKk.pgp Description: PGP signature - List info/subscribe/unsubscribe? See http://www.freeradius.org/list/users.html
RE: realtime for freeradius
yes - realtime scheduling won't be of too much help for throughput-bound services buy may improve the performance characteristics of latency-bound services, especially in small size transaction services. consider clusters of proxying freeradius - no database backend - these servers merely proxy radius requests onto other servers (possibly other organisations)... would real-time scheduling improve the jitter at this layer which sees large numbers of small sized transactions? t -Original Message- From: [EMAIL PROTECTED] g [mailto:[EMAIL PROTECTED] adius.org]On Behalf Of Peter Nixon Sent: 20 September 2006 12:22 To: FreeRadius users mailing list Subject: Re: realtime for freeradius On Wed 20 Sep 2006 14:09, Tariq Rashid wrote: With modern operating systems we have various server task scheduling options available to use. We can either use OSes modified to provide soft real-time such as versions of Linux. We can also ask the task schedulers to give certain processes either higher priority or to give them real-time alike scheduling, as is possible in Solaris and maybe Linux. I wonder of anyone has experimented with observing FreeRadius performance under load conditions with these options? We shouldn't expect faster performance, but we may achieve more consistent behaviour - for example a smaller variance in response times. Thoughts and suggestions welcome. Realtime typically is used for Telecom and Telemetry applications. I can't think of any reason why you would need a radius server to run as realtime however... Generally you are in any case waiting on a backend LDAP or SQL database in any case.. Cheers -- Peter Nixon http://www.peternixon.net/ PGP Key: http://www.peternixon.net/public.asc - List info/subscribe/unsubscribe? See http://www.freeradius.org/list/users.html
Re: realtime for freeradius
Tariq Rashid [EMAIL PROTECTED] wrote: consider clusters of proxying freeradius - no database backend - these servers merely proxy radius requests onto other servers (possibly other organisations)... would real-time scheduling improve the jitter at this layer which sees large numbers of small sized transactions? Probably not. The server keeps track of time in 1s increments internally, rather than using 'struct timeval', and more detailed tracking. So even if the OS scheduled the process better, the internal packet scheduling will probably have high jitter. Alan DeKok. -- http://deployingradius.com - The web site of the book http://deployingradius.com/blog/ - The blog - List info/subscribe/unsubscribe? See http://www.freeradius.org/list/users.html
