Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
SSD partitioning
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware
View previous topic :: View next topic  
Author Message
coviex
n00b
n00b


Joined: 27 Sep 2010
Posts: 31

PostPosted: Thu Apr 18, 2013 1:32 pm    Post subject: SSD partitioning Reply with quote

Hi,

Today after update, which I do everyday, my root ext3 partition on HDD became read-only.
And now root becomes read-only randomly during work and fsck starts after every reboot.
I don't know whether its HDD or something in the update that causes problem but I decided to switch to OCZ Vertex SSD.

Using this article as a guide - http://wiki.gentoo.org/wiki/SSD.
As I understand it itself uses another article as a guide - http://blog.nuclex-games.com/2009/12/aligning-an-ssd-on-linux/
I'm trying to do
Code:
fdisk -S 32 -H 32 /dev/sdb

but fdisk says that "S" and "H" options are deprecated and I feel like this command doesn't do anything.
Using cylinders as units is also deprecated.
That's what I have after a few steps.
Code:

Disk /dev/sdb: 120.0 GB, 120034123776 bytes, 234441648 sectors
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000a700c

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               2         129     1028160   83  Linux

There neither "32 heads" nor "32 sectors" anywhere.
Chunks are too big and resulting partition is almost 1Gb.

What I do wrong?

PS using kernel gentoo 3.7.1 64bit. just in case

Thanks
Back to top
View user's profile Send private message
eccerr0r
Advocate
Advocate


Joined: 01 Jul 2004
Posts: 4104
Location: USA

PostPosted: Thu Apr 18, 2013 3:41 pm    Post subject: Reply with quote

If you have a recent enough fdisk, it should work with LBA as-is, don't bother with specifying cylinders and heads, you don't need to!

However, you can use the fdisk option -c=dos to force it to use the C/H/S mechanism...

Anyway if you use LBA, fdisk makes it fairly simple to use MByte boundaries. It actually defaults to starting the first partition at sector 2048... what's special about 2048? 512 bytes * 2048 sectors = ... tada 1MB. Then use the +1MB, +1GB, etc. to generate partitions perfectly aligned at 1MB boundaries which pretty much encompasses most erase blocks on SSDs.

This of course screws up hard drives that C/H/S should be used on for speed as if you had to stride a cylinder boundary you'd lose performance... but hard drives like this haven't been around for decades... internal mapping have differed from C/H/S for at least 20 years now...
_________________
Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSD
What am I supposed to be advocating?
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum