Dell Perc 5/i Performance issues

[oizs]

I've seen people with the same configuration doing 160MB/s writes and 
250MB/s+ reads with raid5 so I still think something isn't right. And 
using raid10 with 4 disks is a rather large waste of capacity.

-zsozso

On 2010.06.18. 1:55, Chuck Swiger wrote:
> On Jun 17, 2010, at 4:50 PM, oizs wrote:
>    
>> I've bought a Dell Perc 5/i because I couldn't make the onboard marvell 88sx7042 work with 8.0/8.1 or current, but as lucky as I am, the best I can do with 4x1.5tb samsung in raid5 is 60MB/s writes and 90MB/s reads, with bbu/write-back/adaptive-read-ahead.
>>
>> I was expecting at least twice of that, and I'm not sure what can I do to get that speed. (I've read man 7 tuning with no success)
>>      
> Switch to using RAID-10 rather than RAID-5.  It's normal for RAID-5 to have worse write performance than that of a single drive.
>
> Regards,
>