Re: [HACKERS] ice-broker scan thread

[David Boreham]

Qingqing Zhou wrote: On Mon, 28 Nov 2005, Gavin Sherry wrote: MySQL, Oracle and others implement read-ahead threads to simulate async IO 'pre-fetching'. Due to my tests on Windows (using the attached program and change enable_aio=true), seems aio doesn't help as a separate thread - but maybe because my usage is wrong ... I don't think your NT overlapped I/O code is quite right. At least I think it will issue reads at a high rate without waiting for any of them to complete. Beyond some point that has to give the kernel gut-rot. But anyway, I wouldn't expect the use of aio to make any significant difference in an already threaded test program. The point of aio is to allow I/O concurrency _without_ the use of threads or multiple processes. You could re-write your program to have a single thread but use aio. In that case it should show the same read ahead benefit that you see with the thread.