Re: Multi-threaded IO performance regression on 2.6 kernel?

2005-07-21 Thread Miquel van Smoorenburg
In article <[EMAIL PROTECTED]>, Xie, Bill <[EMAIL PROTECTED]> wrote: >All, > >I am testing the multi-threaded IO performance on Opteron servers. > >I use dd as the test tools. The single dd can reach 60MBps for single disk. > >on 2.6.5 kernel, If dd numbers exceed the CPU numbers, vmstat bi reduce

Multi-threaded IO performance regression on 2.6 kernel?

2005-07-21 Thread Xie, Bill
All, I am testing the multi-threaded IO performance on Opteron servers. I use dd as the test tools. The single dd can reach 60MBps for single disk. on 2.6.5 kernel, If dd numbers exceed the CPU numbers, vmstat bi reduced to 20MBps. on 2.4.21 kernel, multi-threaded IO performance works fine, e