Ok. That is very slow. Keep in mind, since you have 2 mirror sets, and 1 single disk, your configuration will not be faster than any single disk. So, typical SAS drive can maybe do about 80MB/sec, so you should expect somewhere between 60-100MB/sec i think.. but that is a guess.
How are you measuring the throughput when you copy a file? Is it something like: rsync -av /path/to/source/file /path/to/destination/file Can you do a read-only or write-only test instead? Maybe using dd if=/dev/zero of=/path/to/logical/volume/testfile bs=1024 count=10240 When you do your copy of file, what is the output of 'iostat' ? can you run 'iostat -m 1 10' during the test? Also, one thing that I've notice makes a big performance difference on the SAS/SATA controllers in Dell servers is the block device read-ahead cache I/O scheduler. To see what your read-ahead cache looks like: blockdev --getra /dev/sda (or whatever the device is) To set it: blockdev --setra 8192 /dev/sda (set it to 8MB) I don't know about mirror sets, but with RAID-5 sets, read-ahead tuning made a big difference in throughput tests. Also, try changing to the 'deadline' I/O scheduler on the device and see if that helps. What is the file system configuration? ext3 or? > -----Original Message----- > From: mcclnx mcc [mailto:[email protected]] > Sent: Thursday, December 03, 2009 5:11 PM > To: [email protected]; Bond Masuda > Subject: RE: R900 internal disks I/O slow!!!! > > sorry it is typo. it is "8 to 9 MB/sec" > > > --- 09/12/3 (四)，Bond Masuda <[email protected]> 寫道： > > > 寄件者: Bond Masuda <[email protected]> > > 主旨: RE: R900 internal disks I/O slow!!!! > > 收件者: "'mcclnx mcc'" <[email protected]>, [email protected] > > 日期: 2009年12月3日,四,下午4:54 > > Hi, > > > > 8 to 9GB/sec is slow? > > > > -Bond > > > > > -----Original Message----- > > > From: [email protected] > > [mailto:linux-poweredge- > > > [email protected]] > > On Behalf Of mcclnx mcc > > > Sent: Thursday, December 03, 2009 1:51 PM > > > To: [email protected] > > > Subject: R900 internal disks I/O slow!!!! > > > > > > we have several R900 server with Redhat 5.3 O.S. in > > it. R900 have 5 > > > internal 450GB SAS disks. we configured it as 0 > > and 1 mirror, 2 and 3 > > > mirror, last disk singe. > > > > > > I have been perform file in between each logical disks > > and I/O is very > > > slow (something like 8 to 9GB/sec). Even my OLD > > DELL 2650 servers > > > (Redhat 4.7) internal disks run fast than it. > > > > > > Does anyone know why? > > > > > > Thanks. > > > > > > ___________________________________________________ > > > 蠟腔汜魂撈媆籵 ㄜ > > 𩆨籵﹜𠸉猸﹜汜魂﹜馱釬珨棒詻隅ㄐ > > > http://messenger.yahoo.com.tw/ > > > > > > _______________________________________________ > > > Linux-PowerEdge mailing list > > > [email protected] > > > https://lists.us.dell.com/mailman/listinfo/linux-poweredge > > > Please read the FAQ at http://lists.us.dell.com/faq > > > > > > ___________________________________________________ > 您的生活即時通 － 溝通、娛樂、生活、工作一次搞定！ > http://messenger.yahoo.com.tw/ _______________________________________________ Linux-PowerEdge mailing list [email protected] https://lists.us.dell.com/mailman/listinfo/linux-poweredge Please read the FAQ at http://lists.us.dell.com/faq
