[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: Using stride on non-RAID



On Mar 15, 2011, at 6:53 PM, Eric Sandeen wrote:

> On 3/15/11 5:42 PM, David Shaw wrote:
>> Hello,
>> 
>> I understand the need for a proper stride setting when formatting a
>> filesystem on a RAID device.  However, is there any problem in using
>> a stride setting when formatting a filesystem on a regular non-RAID,
>> non-SSD, just plain-vanilla-single-disk block device?  I'm sure there
>> isn't any benefit to it, but I'm curious if there is any harm.
>> 
>> The reason I ask is I'm looking at some code here that can be used on
>> either RAID or non-RAID devices.  The stride setting it has is
>> correct for the particular RAID setup it is intended for, but it also
>> uses those settings when formatting a non-RAID device.
>> 
>> David
> 
> just FWIW, recent kernels & e2fsprogs will just automatically pick
> stride based on storage geometry - for md/lvm at least, and for
> scsi devices that export this geometry as well.
> 
> ext4 has a little stripe-awareness in its allocator; otherwise, stride
> just staggers bitmap starts so they don't all end up on the same spindle; [1]
> Offhand I don't think it'd cause any harm to set stride on non-raid.

Thanks very much for your pointers.  It's a nice enhancement that this is done automatically now.

David



[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]