Ok sorry about that. Something else was writing to the disks.

Cheers

Stevo

----------------------------------------

From: scjthm@live.com
To: linux-raid@vger.kernel.org
Subject: Poor performance with raid 0 with 2 devices at partition level
Date: Sun, 6 Jul 2014 06:28:57 +0100

Hi

I have a some problems with a two disk raid 0 array using md. I two disks with advanced format 4096 physical/512 logical sector size. I have two partitions on two disks which are aligned on a divisible by 8 sector boundary. I run dd on each of the paritions using the sync mode, and the block dump tells me that it is writing 8 sectors at a time. I get about 100+Mbytes/second. I create a raid array using the mdadm tools with chunk size of 128Kbytes and I check block dump and it tells me that it is writing 8 sectors at a time on the MD device. When I write to the md device I only get about 8Mbytes/second. On the same machine using full disk raid configured using the intel firmware raid and read by MD I get about 200+ Mbytes/s write speed.

Is there anything that I am doing that is incorrect?


Cheers

Stevo --
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html