On Friday 14. February 2014 09.24.34 Warren Block wrote: > The Problem > > More and more disk devices have native 4K blocks. The ability to align > MBR slices to arbitrary values is consequently becoming more important. > Misaligned filesystems might read or write at less than half the speed > of aligned filesystems on the same disk. > > Microsoft recognized this problem, and at least since the release of > Vista in 2007, MBR-formatted disks created by Microsoft operating > systems have started the first or main filesystem slice at block 2048 > (1M). Despite the official standard for MBR alignment to CHS values, > this second non-CHS but 4K-aligned de facto standard has become > extremely common. *snip* > Suggested Solution > > gpart(8) should be allowed to override the CHS rounding with -a and -b > values when creating MBR slices. If CHS rounding occurs when the > options are not given, gpart(8) should give a warning that default > values were used to avoid surprising the user. > > The warning is really secondary. Primarily and pragmatically, gpart(8) > needs the ability to create MBR slices with arbitrary alignment so > FreeBSD can deal gracefully with modern storage hardware. >
IMHO, 4k alignment should be default in freebsd as well, unless there are some actual disadvantages for the users. I think the majority of users would like good performance. But allowing to override it is a good start :) Ulf _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-geom To unsubscribe, send any mail to "[email protected]"
