问题描述
我的笔记本电脑上有一个HD，有两个分区(一个安装了Ubuntu 12.04的ext3和一个交换)。
fdisk给我一个分区1没有开始物理扇区边界警告。原因是什么，我需要解决它吗？如果是这样，怎么样？
这是sudo fdisk -l：
Disk /dev/sda: 750.2 GB, 750156374016 bytes
255 testine, 63 settori/tracce, 91201 cilindri, totale 1465149168 settori
Unità = settori di 1 * 512 = 512 byte
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Identificativo disco: 0x5a25087f
Dispositivo Boot Start End Blocks Id System
/dev/sda1 * 63 1448577023 724288480+ 83 Linux
Partition 1 does not start on physical sector boundary.
/dev/sda2 1448577024 1465147391 8285184 82 Linux swap / Solaris
这是sudo lshw的相关结果：
*-disk
description: ATA Disk
product: WDC WD7500BPKT-0
vendor: Western Digital
physical id: 0
bus info: scsi@0:0.0.0
logical name: /dev/sda
version: 01.0
serial: WD-WX21CC1T0847
size: 698GiB (750GB)
capabilities: partitioned partitioned:dos
configuration: ansiversion=5 signature=5a25087f
*-volume:0
description: EXT3 volume
vendor: Linux
physical id: 1
bus info: scsi@0:0.0.0,1
logical name: /dev/sda1
logical name: /
version: 1.0
serial: cc5c562a-bc59-4a37-b589-805b27b2cbd7
size: 690GiB
capacity: 690GiB
capabilities: primary bootable journaled extended_attributes large_files recover ext3 ext2 initialized
configuration: created=2010-02-27 09:18:28 filesystem=ext3 modified=2012-06-23 18:33:59 mount.fstype=ext3 mount.options=rw,relatime,errors=remount-ro,user_xattr,barrier=1,data=ordered mounted=2012-06-28 00:20:47 state=mounted
*-volume:1
description: Linux swap volume
physical id: 2
bus info: scsi@0:0.0.0,2
logical name: /dev/sda2
version: 1
serial: 16a7fee0-be9e-4e34-9dc3-28f4eeb61bf6
size: 8091MiB
capacity: 8091MiB
capabilities: primary nofs swap initialized
configuration: filesystem=swap pagesize=4096
这些是相关的/etc/fstab线：
UUID=cc5c562a-bc59-4a37-b589-805b27b2cbd7 / ext3 errors=remount-ro,user_xattr 0 1
UUID=16a7fee0-be9e-4e34-9dc3-28f4eeb61bf6 none swap sw 0 0
最佳解决办法
您的硬盘具有高级格式4096字节扇区，分区未完全对齐
这一行解释了警告：
Sector size (logical/physical): 512 bytes / 4096 bytes-
您的硬盘是较新的型号之一，它使用每个物理扇区4096字节的Advanced Format而不是旧的512字节/扇区。
-
这些HDD仍然可以提供512字节/扇区的”legacy”仿真，这就是您将逻辑扇区大小视为512的原因。
-
事实上，
lshw显示它是西部数据驱动器，是第一家转向AF的公司。 They have an extensive page with lots of information on it，您可能希望看一下。
因此，发生警告是因为分区1开始于逻辑扇区63 =字节32256，一个不能被4096整除的数字;事实上，它接近第7个物理部门的结束(准确地说是7.875位置:)
你应该修好吗？如果是这样，怎么样？ [永远备份！]
理论上，这种分区可能会稍微影响读/写IO速率，具体取决于驱动器的固件。如果您现在对性能感到满意，请忽略该警告，无需执行任何操作。如果没有，先备份所有重要数据，然后使用Gparted移动分区，使其从4096字节扇区开始;将起始边界设置为1 MiB是一种简单的方法。
-
从技术上讲，您可以将开头设置为8的倍数的任何逻辑扇区，例如， 64好，256好，等等，但63,255 ……不是。
次佳解决办法
对于新硬盘，首先根据您的意愿使用gparted创建分区。
然后，使用sudo fdisk device_name访问您的硬盘。 fdisk中的m命令将打印帮助菜单。
npcompete@npcompete-desktop:~$ sudo fdisk /dev/sda
The device presents a logical sector size that is smaller than
the physical sector size. Aligning to a physical sector (or optimal
I/O) size boundary is recommended, or performance may be impacted.
Command (m for help): p
Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 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
Disk identifier: 0x0008e009
Device Boot Start End Blocks Id System
/dev/sda1 2048 209717247 104857600 83 Linux
/dev/sda2 209717248 1953525167 871903960 5 Extended
/dev/sda5 600349113 795667319 97659103+ 83 Linux
Partition 5 does not start on physical sector boundary.
/dev/sda6 795667383 990985589 97659103+ 83 Linux
Partition 6 does not start on physical sector boundary.
/dev/sda7 990985653 1953520064 481267206 83 Linux
Partition 7 does not start on physical sector boundary.
/dev/sda8 209719296 600349112 195314908+ 83 Linux
Partition table entries are not in disk order
Command (m for help): d
Partition number (1-8): 5
Command (m for help): p
Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 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
Disk identifier: 0x0008e009
Device Boot Start End Blocks Id System
/dev/sda1 2048 209717247 104857600 83 Linux
/dev/sda2 209717248 1953525167 871903960 5 Extended
/dev/sda5 795667383 990985589 97659103+ 83 Linux
Partition 5 does not start on physical sector boundary.
/dev/sda6 990985653 1953520064 481267206 83 Linux
Partition 6 does not start on physical sector boundary.
/dev/sda7 209719296 600349112 195314908+ 83 Linux
Partition table entries are not in disk order
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
npcompete@npcompete-desktop:~$ sudo fdisk /dev/sda
The device presents a logical sector size that is smaller than
the physical sector size. Aligning to a physical sector (or optimal
I/O) size boundary is recommended, or performance may be impacted.
Command (m for help): n
Partition type:
p primary (1 primary, 1 extended, 2 free)
l logical (numbered from 5)
Select (default p): l
Adding logical partition 8
First sector (600351161-1953525167, default 600352768):
Using default value 600352768
Last sector, +sectors or +size{K,M,G} (600352768-795667382, default 795667382):
Using default value 795667382
Command (m for help): p
Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 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
Disk identifier: 0x0008e009
Device Boot Start End Blocks Id System
/dev/sda1 2048 209717247 104857600 83 Linux
/dev/sda2 209717248 1953525167 871903960 5 Extended
/dev/sda5 795667383 990985589 97659103+ 83 Linux
Partition 5 does not start on physical sector boundary.
/dev/sda6 990985653 1953520064 481267206 83 Linux
Partition 6 does not start on physical sector boundary.
/dev/sda7 209719296 600349112 195314908+ 83 Linux
/dev/sda8 600352768 795667382 97657307+ 83 Linux
Partition table entries are not in disk order
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
现在删除在fdisk中使用d选项发出警告的分区。
第一个命令d，然后是分区号(在警告中提到)。
现在使用w命令将更改写入磁盘。它将退出fdisk。
第二次使用sudo fdisk device_name访问你的硬盘。
现在使用fdisk中的n命令使用可用空间(以前我们已经删除了一个分区，即可用空间或未分配的空间)创建一个新分区。
在New partition命令中，不要为First和Last Sector输入任何值，只需按Enter键即可。它将采用默认值。
现在使用w命令将更改写入磁盘。它将退出fdisk。
对所有分区执行上述步骤。完成此格式后，使用gparted创建新创建的分区。 (这就是我为我所做的工作。在fdisk -l输出中没有警告。)
第三种解决办法
正如izx所指出的：
your hard disk has Advanced Format 4096-byte sectors to which the partition is not perfectly aligned.
this article很好地解释了高级格式规范及其对user-side硬盘分区实践的影响。
要解决此问题，您必须备份数据，然后执行以下操作之一：
-
将错误大小的分区调整为适当的大小。
-
删除错误大小的分区并创建适当大小的新分区。
要使用名为GParted的图形化hard-drive分区软件来完成此任务，您可以：
-
使用super-user权限启动Gparted应用程序;谨慎行事！
gksudo gparted -
从GParted菜单右上角的pull-down菜单中选择包含错误大小分区的存储设备。
-
通过在矩形分区映射中单击它来选择erroneously-sized分区。
-
现在您可以选择删除并创建新分区，也可以选择调整现有分区的大小。无论您的选择如何，您都会看到一个允许您设置分区大小的菜单。您必须清除“Round to cylinders”复选框并设置1MiB之前的可用空间大小。它看起来很像
。
第四种办法
通过切换”u”单元。创建分区时将显示默认扇区大小。如果您开始分区新磁盘并且出现此错误，则可以。
-
用defaut创建一个分区。
-
n，p，1，回车，回车
-
显示并获取分区错误消息。 “p”。
-
开关单元”u”
-
删除分区。 “d”
-
现在重新创建。这次默认值将显示正确的扇区。 (在我看来是1024)。
Command (m for help): p
Disk /dev/sdb: 599.9 GB, 599932844032 bytes
255 heads, 63 sectors/track, 72937 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 262144 bytes / 524288 bytes
Disk identifier: 0x2016bdc5
Device Boot Start End Blocks Id System
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-72937, default 1): 1
Last cylinder, +cylinders or +size{K,M,G} (1-72937, default 72937):
Using default value 72937
Command (m for help): p
Disk /dev/sdb: 599.9 GB, 599932844032 bytes
255 heads, 63 sectors/track, 72937 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 262144 bytes / 524288 bytes
Disk identifier: 0x2016bdc5
Device Boot Start End Blocks Id System
/dev/sdb1 1 72937 585866421 83 Linux
Partition 1 does not start on physical sector boundary.
Command (m for help): u
Changing display/entry units to sectors
Command (m for help): p
Disk /dev/sdb: 599.9 GB, 599932844032 bytes
255 heads, 63 sectors/track, 72937 cylinders, total 1171743836 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 262144 bytes / 524288 bytes
Disk identifier: 0x2016bdc5
Device Boot Start End Blocks Id System
/dev/sdb1 63 1171732904 585866421 83 Linux
Partition 1 does not start on physical sector boundary.
Command (m for help): d
Selected partition 1
Command (m for help): p
Disk /dev/sdb: 599.9 GB, 599932844032 bytes
255 heads, 63 sectors/track, 72937 cylinders, total 1171743836 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 262144 bytes / 524288 bytes
Disk identifier: 0x2016bdc5
Device Boot Start End Blocks Id System
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 8
Value out of range.
Partition number (1-4): 1
First sector (63-1171743835, default 1024):
Using default value 1024
Last sector, +sectors or +size{K,M,G} (1024-1171743835, default 1171743835):
Using default value 1171743835
Command (m for help): p
Disk /dev/sdb: 599.9 GB, 599932844032 bytes
255 heads, 63 sectors/track, 72937 cylinders, total 1171743836 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 262144 bytes / 524288 bytes
Disk identifier: 0x2016bdc5
Device Boot Start End Blocks Id System
/dev/sdb1 1024 1171743835 585871406 83 Linux
Command (m for help): w
The partition table has been altered!