I completely agree with Axel, expecially speaking about a middle-range machine (as mine, for example, a linux home-assembled server with a careful look at the costs).
Carlo 2014-08-07 14:18 GMT+02:00 Axel Kohlmeyer <akohlmey at gmail.com>: > On Thu, Aug 7, 2014 at 6:56 AM, siddheshwar chopra <sidhusai at gmail.com> > wrote: > > Dear Sir, > > Oh I am sorry... I think I didn't mention correctly.. I said "write > times".. > > It is actually "number of write times". Ofcourse these are very fast..But > > their life is shorter than the normal HDDs... > > Yes budget is what is the final verdict.. :-) > > not only that. but also, how much time you save, i.e. how much value > you attribute to your own time. > if an SSD will wear out and become unusable, you can easily replace it > at the fraction of the cost of the entire machine, and then - provided > an SSD scratch does significantly improve your calculation run times - > you have a faster machine all the time. > > please also note that SSD performance varies a lot and also the amount > of guaranteed writes. > > axel. > > > > > > Regards, > > > > > > On Thu, Aug 7, 2014 at 4:18 PM, Carlo Nervi <carlo.nervi at unito.it> > wrote: > >> > >> I'm not an expert, and maybe my infos are old, but I think you are > wrong. > >> Certain SSD have degraded performances, however the best SSD have much > >> faster access I/O time than than the best HDD. at least for medium > >> workstation. Cost for Gb is of course much higher for SSD, but in this > case > >> I would go only for a working directory to be placed on a SSD partition > (128 > >> Gb could be enough). I do not know how is the situation for high-end > >> enterprise solutions or supercomputers, but in this case i suspect that > the > >> special HDDs are not connected via simple SATA or SAS, and in these > cases > >> very probably they are much faster (again at much hgher prices) due > several > >> optimized performances (independent memory cache, for example). > >> > >> In other words, it depend how much is your budget... > >> Cheers, > >> Carlo > >> > >> > >> > >> 2014-08-07 11:42 GMT+02:00 siddheshwar chopra <sidhusai at gmail.com>: > >>> > >>> Dear Sir, > >>> I just want to participate in this good discussion. I read somewhere > that > >>> Solid State Hard Disk has LESSER write times than a normal HDD. Yes > >>> undoubtedly it is the fastest we have in the market with low power > >>> consumption and zero mechanical failure risk, but at the cost of > shorter > >>> lives and more money. > >>> Any comments welcome.. > >>> > >>> Regards, > >>> > >>> > >>> On Thu, Aug 7, 2014 at 2:16 PM, Carlo Nervi <carlo.nervi at unito.it> > wrote: > >>>> > >>>> My two cents: even though there are differences between SAS and SATA, > >>>> they are not so huge. > >>>> From this point of view I guess that a fast Solid State Hard Disk > would > >>>> make the difference on the I/O. > >>>> > >>>> > >>>> > >>>> 2014-08-07 10:06 GMT+02:00 Paolo Giannozzi <paolo.giannozzi at uniud.it > >: > >>>> > >>>>> On Wed, 2014-08-06 at 18:15 -0400, Eduardo Menendez wrote: > >>>>> > >>>>> > Is it critical to use SAS disks (compared to SATA) for good > >>>>> > performance of Quantum ESPRESSO? > >>>>> > >>>>> I guess it depends upon the amount of I/O you plan to do > >>>>> > >>>>> Paolo > >>>>> > >>>>> -- > >>>>> Paolo Giannozzi, Dept. Chemistry&Physics&Environment, > >>>>> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy > >>>>> Phone +39-0432-558216, fax +39-0432-558222 > >>>>> > >>>>> _______________________________________________ > >>>>> Pw_forum mailing list > >>>>> Pw_forum at pwscf.org > >>>>> http://pwscf.org/mailman/listinfo/pw_forum > >>>> > >>>> > >>>> > >>>> > >>>> -- > >>>> > >>>> ------------------------------------------------------------ > >>>> Prof. Carlo Nervi carlo.nervi at unito.it Tel:+39 0116707507/8 > >>>> Fax: +39 0116707855 - Dipartimento di Chimica, via > >>>> P. Giuria 7, 10125 Torino, Italy. http://lem.ch.unito.it/ > >>>> > >>>> > >>>> _______________________________________________ > >>>> Pw_forum mailing list > >>>> Pw_forum at pwscf.org > >>>> http://pwscf.org/mailman/listinfo/pw_forum > >>> > >>> > >>> > >>> > >>> -- > >>> Dr. Siddheshwar chopra, > >>> M.Sc., Ph.D (Physics) > >>> Assistant Professor (Physics), > >>> Amity University, Noida, India. > >>> > >>> > >>> _______________________________________________ > >>> Pw_forum mailing list > >>> Pw_forum at pwscf.org > >>> http://pwscf.org/mailman/listinfo/pw_forum > >> > >> > >> > >> > >> -- > >> > >> ------------------------------------------------------------ > >> Prof. Carlo Nervi carlo.nervi at unito.it Tel:+39 0116707507/8 > >> Fax: +39 0116707855 - Dipartimento di Chimica, via > >> P. Giuria 7, 10125 Torino, Italy. http://lem.ch.unito.it/ > >> > >> > >> _______________________________________________ > >> Pw_forum mailing list > >> Pw_forum at pwscf.org > >> http://pwscf.org/mailman/listinfo/pw_forum > > > > > > > > > > -- > > Dr. Siddheshwar chopra, > > M.Sc., Ph.D (Physics) > > Assistant Professor (Physics), > > Amity University, Noida, India. > > > > > > _______________________________________________ > > Pw_forum mailing list > > Pw_forum at pwscf.org > > http://pwscf.org/mailman/listinfo/pw_forum > > > > -- > Dr. Axel Kohlmeyer akohlmey at gmail.com http://goo.gl/1wk0 > College of Science & Technology, Temple University, Philadelphia PA, USA > International Centre for Theoretical Physics, Trieste. Italy. > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -- ------------------------------------------------------------ Prof. Carlo Nervi carlo.nervi at unito.it Tel:+39 0116707507/8 Fax: +39 0116707855 - Dipartimento di Chimica, via P. Giuria 7, 10125 Torino, Italy. http://lem.ch.unito.it/ -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20140807/7320f8a7/attachment.html
