From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Schwarz Subject: Soft-Raid 0 Performance | Transfer two Data-Streams (CPU+FPGA) to the same Soft-Raid Date: Tue, 17 Jan 2017 16:00:47 +0100 Message-ID: <0e04b53af8bdf4f39a08b31ea4499626@sw-optimization.com> References: <21298bd64ef0dc83b29bd45362ead46c@sw-optimization.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <21298bd64ef0dc83b29bd45362ead46c@sw-optimization.com> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Hello mailing list, I have got two questions: 1.) I have set-up a softraid (raid level 0) with mdadm using two M.2 modules. For one module the throughput is ~350MB/s (no mdadm) for two modules the throughput is ~500MB/s which is less than factor 1,5 of the throughput of a single drive. The filesystem used is ext4. Is there someone having some values for comparison? For me the throughput gain seems to be too little. The test was done using a HP Z840 workstation. 2.) We want to configure a softraid (raid level 0) with mdadm which can be used from within Linux but also it should be possible to write data to the raid w/ DMA directly from the FPGA which is also connected to the PCIe bus as a slave as well as the M.2 modules. How can that be achieved using existing kernel infrastructure? Many thanks for helpful replies Eric