On 05/06/2015 04:32 PM, Vladimir Mosgalin wrote:
> Hi ToddAndMargo!
>
> On 2015.05.06 at 00:48:30 -0700, ToddAndMargo wrote next:
>
>> http://www.intel.ie/content/dam/www/public/us/en/documents/white-papers/ssd-dc-s3500-workload-raid-paper.pdf
>>
>>
>> The system used for RAID 1 testing include the following:
>> • LSI MegaRAID 9265-8i* controller card
>>
>> To summarize:
>> • In both RAID 1 and RAID 5, the Intel SSD DC S3500 Series
>> drive shows excellent scalability, performance, and consistency.
>>
>> • Very little latency was introduced by the RAID controller
>> in RAID 1. In RAID 5, the overhead and latency are slightly
>> higher.
>>
>> • In random, mixed read/write workloads, SSDs perform
>> significantly (as much as 100 times) better than HDDs
>> in a similar situation
>>
>>
>> Maybe the S3500 is what I want? They are still available
>> at my distributors.
>
> They are fine drives. In fact, I got servers running them; excellent
> performance, no problem with incompressible data (unlike drives with SF
> controllers) - this matters to me because I'm using zfs on linux with
> compression. Sustained write speed >500 MB/s (480GB model).
>
> However, like I said before, if long-term performance is needed,
It is, but it will be in a high end workstation. 99% of the
writes will be OS related and not user related.
> I
> advise against using them in hardware RAID controller. This document
> only shows after-install performance; they didn't do any endurance
> testing. Without TRIM, performance of this drive will degrade.
> Buy Plextor M5/M6 if your environment doesn't support TRIM.
>
>
> I'm curious, what stops you from using software RAID with mdadm?
> For two-disk RAID 1 it provides excellent performance, high
> compatibility and TRIM support. I could understand if you needed
> hardware controller for RAID6 with tons of disks, in RAID6 or something,
> but for two-disk RAID1?..
>
> --
>
> Vladimir
>
Hi Vladimir,
I am allergic to software RAID. I adore the way an independent
controller works.
Thank you for helping me with this,
-T
--
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They malfunction when you open windows
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