Re: slow lvm

Bachsau NetWorX <[email protected]>
Newsgroups gmane.linux.debian.user.isp
Message-ID <[email protected]>
Why does it look weird to you? Every start sector is divisible by 8 so 
you should be fine.

Am 11.08.2011 15:40, schrieb mimo:
> On Thursday 11 August 2011 12:52:36 Bachsau WebWorX wrote:
>> Now, you have to make your partitions to start at megabyte boundaries to
>> get full speed, so that the sectors oft the file system come to lie on
>> the physical sectors, or else it will need read out every sector before
>> writing to it.
>
> Thanks for everyone's help. I found something about these "Green" drives going to park every 8 secs so I used
>
> hdparm -S 242 /dev/sdd
>
> to change the standby. That brought a tiny improvement. So the next step I deleted the whole lvm and used some other advice by running
>
> cfdisk -h 224 -s 56 /dev/sdd
>
> Which gives a partition table that isn't at all divisible by 8 or start on 2048 but performance had improved quite dramatically. Originally I got 71MB/s when writing one large 20GB file. Writing to a raw partition I now get 117MB/s (also with lvm). Is that what I should be achieving?
>
> I just wonder whether I've got it right now as the partition table looks plain weird..
>
> fdisk -lu /dev/sdd
>
> Disk /dev/sdd: 2000.4 GB, 2000398934016 bytes
> 224 heads, 56 sectors/track, 311465 cylinders, total 3907029168 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: 0x0005f6d7
>
>     Device Boot      Start         End      Blocks   Id  System
> /dev/sdd1   *          56    19531007     9765476   fd  Linux raid autodetect
> /dev/sdd2        19531008    39062015     9765504   fd  Linux raid autodetect
> /dev/sdd3        39062016   136717055    48827520   fd  Linux raid autodetect
> /dev/sdd4       136717056  3907016959  1885149952   fd  Linux raid autodetect
>
>
> mimo
>
>
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.