daniel at danielknoll.de
2011-May-27 17:30 UTC
[asterisk-users] More Cores or more CPU Speed
Hi Guys, in next week i plan to upgrade my Asterisk Server. To buy the optimal Hardware i have a question. What is better more cores (eg. 2x quadcore) or more CPU speed for a server that handle a lot of of Meetme Concerences with hundreds of concurrent G711 alaw Channels (no transcoding) ? in my opinion, more cores are better, because Asterisk ist multithreded and each channel has a good chance to distribute to the cores. is that right or what do you think? Thanks for your answers. Daniel
On Fri, May 27, 2011 at 05:30:02PM +0000, daniel at danielknoll.de wrote:> > What is better more cores (eg. 2x quadcore) or more CPU speed for a server > that handle a lot of of Meetme Concerences with hundreds of concurrent G711 > alaw Channels (no transcoding) ? > > in my opinion, more cores are better, because Asterisk ist multithreded and > each channel has a good chance to distribute to the cores. > > is that right or what do you think?I don't have an answer for you (too many unknown variables to say one way or another) but I do know that MeetMe currently is serialized onto a single CPU. For example, all the conference participants threads queue up their audio data on their pseudo channels which can happen in parallel on SMP systems. Then they wait for the "masterspan" to mix the audio for all conferences currently active. This happens on a single CPU to simplifly keeping channels synchronized to whatever timing source is your master. When this was originally written there were not too many SMP systems in use. Then the mixed audio is queued back on the channels. Finally, all the user space channel threads can read out the mixed audio which can happen in parallel on SMP. If you have too many conferences, one CPU may not be able to mix all the audio and you will have audio problems even if there are 7+ other CPUs that are essentially idle while waiting for one CPU to mix everything. You should be able to handle 512 conference participants on a modern server system without problem. The current trunk of DAHDI linux limits the number of open pseudo channels to 512 for this reason. [1] [1] http://svn.asterisk.org/view/dahdi?view=revision&revision=9610 The new ConfBridge module in the upcoming 1.10 release may not have this limitation. -- Shaun Ruffell Digium, Inc. | Linux Kernel Developer 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA Check us out at: www.digium.com & www.asterisk.org
---------------------------------------- From: daniel at danielknoll.de Sent: Friday, May 27, 2011 1:30 PM To: asterisk-users at lists.digium.com Subject: [asterisk-users] More Cores or more CPU Speed Hi Guys, in next week i plan to upgrade my Asterisk Server. To buy the optimal Hardware i have a question. What is better more cores (eg. 2x quadcore) or more CPU speed for a server that handle a lot of of Meetme Concerences with hundreds of concurrent G711 alaw Channels (no transcoding) ? in my opinion, more cores are better, because Asterisk ist multithreded and each channel has a good chance to distribute to the cores. is that right or what do you think? Thanks for your answers. Daniel Daniel I would use a Single AMD 8 or 12 Core processor. They work great for us and you can't beat price for the complete package. It blows intel out of the water per core pricing. If you really want to go wiled you could use a Dual Processer 8 or 12 core system and then your in for a ride. We have been having great luck with the Supermicro boards and the 6100 series AMD processors. Bryant (ZK Tech Inc.) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.digium.com/pipermail/asterisk-users/attachments/20110527/24411000/attachment.htm>