Chris,
Do you mind sharing the drive models & controllers you're using that
give you 800 MB/s?
On Tue, Nov 10, 2009 at 7:18 PM, Chris Worley <worleys@xxxxxxxxx> wrote:
> On Tue, Nov 10, 2009 at 9:01 AM, Majed B. <majedb@xxxxxxxxx> wrote:
>> Which disks can provide 2ms response with a read of 250 MB/s and write
>> of 170 MB/s other than SSDs?!
>
> The drives I use average <50usecs latency at 4KB packets (properly
> measured as the complete turn-around time of a single outstanding
> I/O), 800MB/s reads and >600MB/s writes at 128KB blocks.
>
>>
>> Are you saying that it doesn't matter whether we use Linux or Windows
>> with SSDs because the limitation is coming from the disk's controller
>> itself?
>
> To some degree, yes, when using SSD's behind a controller, the
> controller is the biggest performance issue, and given they use
> chicklets for processors, they all hamper performance given the speed
> potential of the underlying storage.
>
> As none of the enterprise distros are handling TRIM yet, W7 can claim
> it was first, and putting together a TRIM-capable kernel is manual
> currently in Linux, and given only ext4 supports it (strangely, FAT
> supported it, then the code was pulled... XFS may support it, but I
> believe that's still in the works), you have the additional problem
> that ext4 has some maturity issues. Porting "discard" to ext2/3 would
> not be too difficult, especially w/o journal considerations.
>
> Chris
>>
>> On Tue, Nov 10, 2009 at 6:58 PM, Chris Worley <worleys@xxxxxxxxx> wrote:
>>> On Tue, Nov 10, 2009 at 8:43 AM, Majed B. <majedb@xxxxxxxxx> wrote:
>>>> Does that mean we won't be able to squeeze the juice out of Intel's
>>>> Extreme SSDs on Linux?
>>>
>>> The limitation is in the design. You'll be able to get as much
>>> performance as they can offer, given the bad design (of putting SSS
>>> behind legacy controllers).
--
Majed B.
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