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dual-core CPUs

What do you think about dual-core CPUs? Is it a good idea to use them in a SQL Server 2005 machine? Have you ever worked with such a machine? From the performance point of view, a dual-core CPU is not as good as 2 equivalent single-core CPUs, isn’t it? But is its performance rather like 90% or 70% of the latter one? — "Recommended By Dr. Audioscrobbler."
http://www.last.fm/user/chopeen/

As for a Dual Core processor, it would depends on how Windows as an OS would abstract it and present it to rest of the applications – if it presents it as a dual proc, then SQL uses all the available processors.<br /><br />We were thinking about dual-core CPUs, but due to licensing costs this was thrown out of window [<img src=’/community/emoticons/emotion-1.gif’ alt=’:)‘ />].<br /><br /><hr noshade size="1"><b>Satya SKJ</b><br />Contributing Editor & Forums Moderator<br /<a target="_blank" href=http://www.SQL-Server-Performance.Com>http://www.SQL-Server-Performance.Com</a><br /><center><font color="teal"><font size="1">This posting is provided “AS IS” with no rights for the sake of <i>knowledge sharing.</i></font id="size1"></font id="teal"></center>
Due to licensing costs?? SQL Server is licensed on a per socket basis Satya. A two processor dual-core server is essentially four processors. These are actual processors, as opposed to the HTT type of processing from Intel. Since there are only two sockets, you pay for two processor licenses. MS has enforced that this will remain their policy in the foreseeable future. MeanOldDBA
[email protected] When life gives you a lemon, fire the DBA.
a dual core 2.8GHz is exactly like 2 single core 2.8GHz, assuming both have the same cache.
its just that it is still possible to get the single core at slightly higher freq., so some apps not designed for parallel ops will do better in the faster single core
quote:Originally posted by joechang a dual core 2.8GHz is exactly like 2 single core 2.8GHz, assuming both have the same cache.
But don’t the cores need to share some resources between them? For example, cache – does each core has its onw cache?
And there’s one socket instead of two – doesn’t this slow down the communication with the rest of the machine?
quote:Originally posted by joechang its just that it is still possible to get the single core at slightly higher freq., so some apps not designed for parallel ops will do better in the faster single core
That’s not a problem in case of SQL Server. — "Recommended By Dr. Audioscrobbler."
http://www.last.fm/user/chopeen/

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by satya</i><br /><br />We were thinking about dual-core CPUs, but due to licensing costs this was thrown out of window [<img src=’/community/emoticons/emotion-1.gif’ alt=’:)‘ />].<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote"><br />I agree with Derrick on this – what do you mean, Satya?<br /><br />–<br /><br /><i>"Recommended By Dr. Audioscrobbler." <br /<a target="_blank" href=http://www.last.fm/user/chopeen/>http://www.last.fm/user/chopeen/</a></i>
the current Intel dual cores have separate caches, but it is possible to get bigger cache on the single core 2M vs. 1M.
the new CPU scheduled for late 06 may have shared L2 cache,
there are some arguments that a shared 2M is better than 2 separate 1M cache.
AMD may already have this, not sure. there is no reduction in comm capability between 2 cores in one socket vs 2 sockets. in fact it possible to build between comm in multi-core (IBM Power5) but this has not been done in the Intel line yet.
Dual core procs are great especially for scalability. They work just like having multiple procs. We use AMD’s dual core procs. Performance wise their much better than Intel’s procs right now.
Guys<br />This was used for a small project where they don’t want to spend the money, but wanted to get optimum performance with high-end configuration [<img src=’/community/emoticons/emotion-5.gif’ alt=’;)‘ />]. Even though I have explained the cost is not a factor and a way to get around, the PM is too reluctant .. they have ended up using normal server with horrible performance. [}<img src=’/community/emoticons/emotion-1.gif’ alt=’:)‘ />].<br /><blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by chopeen</i><br /><br /><blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by satya</i><br /><br />We were thinking about dual-core CPUs, but due to licensing costs this was thrown out of window [<img src=’/community/emoticons/emotion-1.gif’ alt=’:)‘ />].<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote"><br />I agree with Derrick on this – what do you mean, Satya?<br /><br />–<br /><br /><i>"Recommended By Dr. Audioscrobbler." <br /<a target="_blank" href=http://www.last.fm/user/chopeen/>http://www.last.fm/user/chopeen/</a></i><br /><hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote"><br /><br /><hr noshade size="1"><b>Satya SKJ</b><br />Contributing Editor & Forums Moderator<br /<a target="_blank" href=http://www.SQL-Server-Performance.Com>http://www.SQL-Server-Performance.Com</a><br /><center><font color="teal"><font size="1">This posting is provided “AS IS” with no rights for the sake of <i>knowledge sharing.</i></font id="size1"></font id="teal"></center>
Ahh, tell them congratulations. Idiots once again make the wrong decision and cost the company money by trying to make a name for themselves and not listen to the experts they hired to do the job. Good job. Dilbert is so real. [<img src=’/community/emoticons/emotion-1.gif’ alt=’:)‘ />]<br /><br />MeanOldDBA<br />[email protected]<br /><br />When life gives you a lemon, fire the DBA.
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