Turbo I could see, especially if you're lightly loaded with single-process workloads. That scenario means you're mostly limited by processor clock speed. How significant that is will depend on what processor you've got, what multipliers it uses, etc.
Are you seeing benefits to hyperthreading? In our experiments it's been at best, negligible improvement, and more often a significant slowdown. But it's been a year or two since I did those tests. Lloyd Brown Systems Administrator Fulton Supercomputing Lab Brigham Young University http://marylou.byu.edu On 05/08/2014 12:25 PM, Atom Powers wrote: > Not necessarily. On any recent CPU with "turbo" or any CPU with > Hyperthreading you can experience a performance impact when more than > about half the cores are in use. More use also means more heat which, on > some system, will cause the CPU to clock down. > > > On Thu, May 8, 2014 at 11:18 AM, Lloyd Brown <[email protected] > <mailto:[email protected]>> wrote: > > > Doesn't this imply that somebody is using more resources than they're > supposed to? Essentially this shouldn't occur unless there is resource > contention on the node. Am I missing something? > > Lloyd Brown > Systems Administrator > Fulton Supercomputing Lab > Brigham Young University > http://marylou.byu.edu > > On 05/08/2014 12:14 PM, Atom Powers wrote: > > The specific issue that I want to address is: > > "My job runs slower when there are other jobs on the same node and > some > > of the nodes are unused, why doesn't my job run on the unused nodes?" > > > > > -- > Perfection is just a word I use occasionally with mustard. > --Atom Powers--
