Re: Understanding effect of read-ahead on open-iscsi block device

2008-04-11 Thread Pasi Kärkkäinen
On Tue, Apr 08, 2008 at 10:09:19PM +0300, Pasi Kärkkäinen wrote: On Mon, Apr 07, 2008 at 10:24:56PM +0300, Pasi Kärkkäinen wrote: Hello list! I have lvm volume (from a single sata disk) exported with IET like this: Target iqn.2001-04.com.test:vol1 Lun 0

Re: Understanding effect of read-ahead on open-iscsi block device

2008-04-08 Thread Pasi Kärkkäinen
On Tue, Apr 08, 2008 at 09:45:06AM -0400, Konrad Rzeszutek wrote: What is the MTU set on your NICs? If it is 1500 (the default) a 4KB transfer will have to be divided in four TCP packets and re-assembled on the target side. This increases the amount of work that the TCP stack

Re: Understanding effect of read-ahead on open-iscsi block device

2008-04-07 Thread Konrad Rzeszutek
On Mon, Apr 07, 2008 at 10:24:56PM +0300, Pasi Kärkkäinen wrote: Hello list! I have lvm volume (from a single sata disk) exported with IET like this: Target iqn.2001-04.com.test:vol1 Lun 0 Path=/dev/vg1/test1,Type=fileio InitialR2T No ImmediateData