On 1/21/2012 6:53 AM, Michael Tokarev wrote: > On 21.01.2012 15:42, Michael Tokarev wrote: >> On 20.01.2012 16:01, Stan Hoeppner wrote: > [] >>> As it turns out the OP has Seagate LP drives which are not Advanced >>> Format 512/4096 drives. No alignment issue there. >> >> I never had/usd these so don't know. Apparently the LP drives >> are more optimized for sequentional operations, since they're >> positioned for various media tasks (movies, photos etc) - but >> again it is difficult to say what is "optimization" here. > > There are 2 modifications of Barracuda LP drives. For 1Gb > models, these are LP ST31000520AS (with traditional 512-sized > sectors)
Seagate is apparently playing a shell game with branding. They sell some of the 512 byte/sector 5.9K rpm "LP" drives as both "LP" and "Green" models. Regardless all "LP" drives are 512B/sector. and LP ST1000DL002, with advanced format (4kb phys > sectors). Both has 5.9KRPM rotation speed. FWIW. ST1000DL002 is a Barracuda Green, not a Barracuda LP, according to Seagate's branding. And according to Seagate, all of the 5900 rpm "Barracuda LP" drives from 500GB to 2TB have 512 byte sectors: http://www.seagate.com/docs/pdf/datasheet/disc/ds_barracuda_lp.pdf Due to Seagate's cross-branding I guess it's possible his drives are actually 4096byte/sector models. In which case mis-alignment is a possible factor in his horrible fsync performance. It's impossible to say as the OP didn't state the actual model number. On a _technical_ mailing list that's really a requirement. >> And having said all that, I think it'd be interesting to >> understand why the OP has this slow system. It should not >> be this slow, with non-AF drives (misalignment for AF drives >> can explain this slowness, and that's the only thing I can >> think of right now). Yes there are several layers of storage, >> but that should not be _that_ bad. Maybe that's the LP drives, >> I dunno. > > So it very well might be due to misalignment. It's probably a combination of things. But lacking further information from Konrad there's nothing further we can do but fruitlessly speculate. So until we have more information I think this thread should die. -- Stan
