Alinear discos de bloques físicos de 4k
Causa
Nuevos discos tienen bloques físicos de 4k, en vez de 512Bytes.
livecd mnt # mkfs -t ext2 /dev/sda1
mke2fs 1.42.10 (18-May-2014)
/dev/sda1 alignment is offset by 512 bytes.
This may result in very poor performance, (re)-partitioning suggested.
Creating filesystem with 32096 1k blocks and 8032 inodes
Filesystem UUID: 0df3d54f-588b-4656-b609-0378fc773711
Superblock backups stored on blocks:
8193, 24577
Allocating group tables: done
Writing inode tables: done
Writing superblocks and filesystem accounting information: done
Vemos que cfdisk no ha puesto los sectores alineados con los sectores físicos.
livecd mnt # fdisk -lu /dev/sda Disk /dev/sda: 465.8 GiB, 500107862016 bytes, 976773168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disklabel type: dos Disk identifier: 0x00000000 Partition 1 does not start on physical sector boundary. Partition 2 does not start on physical sector boundary. Partition 3 does not start on physical sector boundary. Partition 4 does not start on physical sector boundary. Partition 5 does not start on physical sector boundary. Partition 6 does not start on physical sector boundary. Device Boot Start End Blocks Id System /dev/sda1 63 64259 32098+ 83 Linux /dev/sda2 64260 8064629 4000185 83 Linux /dev/sda3 * 8064630 47134709 19535040 83 Linux /dev/sda4 47134710 976773167 464819229 5 Extended /dev/sda5 47134773 351635822 152250525 8e Linux LVM /dev/sda6 351635886 976773167 312568641 fd Linux raid autodetect
Crear las particiones con fdisk
fdisk crea las particiones contando los bloques físicos de 4k
fdisk /dev/sda livecd mnt # fdisk -lu /dev/sda Disk /dev/sda: 465.8 GiB, 500107862016 bytes, 976773168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disklabel type: dos Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/sda1 2048 67583 32768 83 Linux /dev/sda2 67584 8456191 4194304 82 Linux swap / Solaris /dev/sda3 8456192 50399231 20971520 83 Linux /dev/sda4 50399232 976773167 463186968 5 Extended /dev/sda5 50401280 675541679 312570200 fd Linux raid autodetect /dev/sda6 675545088 976773167 150614040 8e Linux LVM
La herramienta fdsik crea las particiones en los bloques físicos.
livecd mnt # mkfs -t ext2 /dev/sda1
mke2fs 1.42.10 (18-May-2014)
Creating filesystem with 32768 1k blocks and 8192 inodes
Filesystem UUID: b6d55569-ff8a-43c0-a566-2f86eb7aefca
Superblock backups stored on blocks:
8193, 24577
Allocating group tables: done
Writing inode tables: done
Writing superblocks and filesystem accounting information: done
Referencias
--Daniel Simao (Talk) 16:24 30 jul 2014 (UTC)
