On Thu, 25 Feb 2010 11:48:27 +0200 Veli Cakmak <veli.li...@gmail.com> wrote:
> Dear Friends; > > I have servers which contain SATA disks and SAS disks. I was testing the > speed of writing on these servers and I recognized that SAS 10.000 disks > much more slowly than the SATA 7200. What do you think about this slowness? > What are the reasons of this slowness? > > > > Thank you for your help. > > > > > > I am giving the below rates (values) which I took from my test (from my > comparisons between SAS 10.000 and SATA 7200); > > > > > > dd if=/dev/zero of=bigfile.txt bs=1024 count=1000000 when this comment was > run in SAS disk server, I took this output(10.000 rpm) > > (a new server,2 CPU 8 core and 8 gb ram) > > 1000000+0 records in > > 1000000+0 records out > > 1024000000 bytes (1.0 GB) copied, 12.9662 s, 79.0 MB/s (I have not used this > server yet) (hw raid1) Your testchunk is smaller than your RAM, so you test mainly the performance of your cache. You also have different RAID-configurations. Try these tests again with 100GB data, at least 3 times with every disk you want to test. At the same server. Then you may start comparing results. Dirk. -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20100225111316.b196a0ba.neu...@yahoo.de
