On Wednesday, May 8, 2013 16:46, "Chris Murphy" <li...@colorremedies.com> said:
> On May 8, 2013, at 2:37 PM, cr...@gtek.biz wrote: > >> On Wednesday, May 8, 2013 13:17, "Chris Murphy" <li...@colorremedies.com> >> said: >> >> Thanks for responding Chris! >> >>> On a 512byte physical and logical sector hard drive, the messages can be >>> ignored. >>> Alignment isn't an issue. >> >> Wouldn't the generation of an error message, when no error condition exists, >> be >> considered a bug? At the very least I would think it would be undesirable. > > It's an older version of parted. I'd try it with 3.1. In any case, it's > difficult > because while 512B physical/logical sector drives should default to an > alignment > value of 1 sector, this probably isn't good for most SSDs which claim a 512B > physical/logical sector size. The way it works now by default is to align on > 1MB > boundaries regardless of the physical sector size. Thanks Chris, excellent point about the version. I stick with Debian's packages whenever I can, but I certainly don't mind trying the latest version of parted. I will let you know how that goes. In the meantime, do you mind if I post a pointer to our conversation here back on the Debian User list for anyone that might be following it there? > > It's possible in your case the warning is about another partition which isn't > aligned, rather than the new one you're trying to create. If that's the case, > the > error message is misleading. > >> >> What about a 4096 physical sector drive? > > Alignment on a 4Kn AF HDD is also a non-factor. There's nothing to align. But > I > still think the default is 1MB alignment with new versions of parted. As a > data > drive, they work. For boot drives, even recent firmware, let alone older > firmware, > don't like them at all. > > For 512e AF HDD, alignment is a considerable factor depending on the firmware > implementation. It's best to align. I would be more than happy to put together any helpful documentation if you or someone else would give me some guidelines on what to put in it. >> >>> For SSDs which effectively lie about their physical sector size, the >>> consequences >>> of miss alignment are variable the firmware. >> >> If mis-alignment can negatively impact performance, I would expect a >> documented >> procedure on avoiding it. Or is my expectation out of line? I certainly >> wouldn't >> mind helping document the procedure if I could get a clear understanding on >> how >> what the procedure is. > > It would be nice if it worked this way, but in reality solid state storage is > in > flux on both a physical level, as well as a firmware (the thing most > responsible > for the logical abstraction from the physical drive). Firmware makes a huge, > huge > difference in SSD behavior. > > > Chris Murphy Most appreciatively, Craig Sent - Gtek Web Mail
