On Fri, Sep 21, 2012 at 05:03:41AM +0800, ching wrote:
> AFAIK, the autodefrag will read related extents and mark them dirty,
> io niceness should be applicable to the read operation
I was hesitant to believe that, but tried it and it's right:
$ dd if=/dev/zero bs=4k count=1 seek=15 of=file
$ dd
>> Is there any io niceness control for autodefrag process too? it will
>> be nice if the idle class is used.
> No. Autodefrag will mark file data dirty and they'll be written back to
> the storage in the same way as any other write through the worker
> threads.
>
>
AFAIK, the autodefrag will rea
On Wed, Sep 19, 2012 at 07:39:42PM +0200, Martin Steigerwald wrote:
> > >>(P.S. I am aware that autodefrag will introduce extra write I/O)
> >
> > Yes, your understanding is right, random write workloads will benefit
> > from it.
>
> What about the extra I/O? And the greatly reduced seek time
On Thu, Sep 20, 2012 at 07:36:53AM +0800, ching wrote:
>
> >>> 2. AFAIK, "autodefrag" detects small random writes into files and
> >>> queues them up for an automatic defrag process, so the filesystem will
> >>> defragment itself while it's used.
> >>>
> >>> If the system reboot/crash/remount-
>>> 2. AFAIK, "autodefrag" detects small random writes into files and
>>> queues them up for an automatic defrag process, so the filesystem will
>>> defragment itself while it's used.
>>>
>>> If the system reboot/crash/remount-ro, will the autodefrag process
>>> continue after resume?
>>>
> Fo
Am Mittwoch, 19. September 2012 schrieb Liu Bo:
> On 09/19/2012 07:28 PM, ching wrote:
[…]
> > On 09/17/2012 07:15 PM, ching wrote:
> >> I am testing btrfs for long-term storage and backup, and i would
> >> like to know more about "autodefrag" option:
> >>
> >> 1. Will "autodefrag" option benefit
On 09/19/2012 07:28 PM, ching wrote:
> can anybody helps?
>
> On 09/17/2012 07:15 PM, ching wrote:
>> I am testing btrfs for long-term storage and backup, and i would like
>> to know more about "autodefrag" option:
>>
>> 1. Will "autodefrag" option benefit ssd?
>>
>> My understanding is:
>>
>>
can anybody helps?
On 09/17/2012 07:15 PM, ching wrote:
> I am testing btrfs for long-term storage and backup, and i would like
> to know more about "autodefrag" option:
>
> 1. Will "autodefrag" option benefit ssd?
>
> My understanding is:
>
>autodrag -> number of extent decrease -> me
I am testing btrfs for long-term storage and backup, and i would like
to know more about "autodefrag" option:
1. Will "autodefrag" option benefit ssd?
My understanding is:
autodrag -> number of extent decrease -> metadata decrease -> a
"healthier" filesystem in the long run
(P.S.
