On Wed, Jan 7, 2015 at 3:30 PM, John R Pierce <pierce at hogranch.com> wrote: >> >> Right... but only cost 133% (about) more than consumer drives, as opposed >> to the 300% that the "server/enterprise" grade drives' cost. > > > well, those $$$ drives are likely SAS rather than SATA, and that has other > advantages... 10k or 15k RPM gives you up to double the IOPS per spindle of > a 7200rpm SATA drive (and WD Reds are only 5900 RPM, I believe?)... 2.5" > enterprise disks let you have more smaller spindles in the same space (24-25 > per 2U vs 12 for 3.5") for higher IO concurrency, and SAS supports > multipathing (dual porting) for higher IO bandwidth, also SAS has tagged > command queueing which often performs better than SATA NCQ under high IO > concurrency workloads, like database servers. These particular drives are enterprise SAS versions, but about as old as they made them. -- Les Mikesell lesmikesell at gmail.com