Poor read performance when sequential write presents

[chen, xiangping]

Hi,

I did a IO test with one sequential read and one sequential write 
to different files. I expected somewhat similar throughput on read
and write. But it seemed that the read is blocked until the write
finishes. After the write process finished, the read process slowly
picks up the speed. Is Linux buffer cache in favor of write? How
to tune it?

Thanks,

Xiangping Chen