Hello, On the state-of-art of asynchronous I/O in Linux. I understand we have full support for AIO in the Linux 2.6.x kernel but I cannot find how to use it from user space. I would like to exploit AIO in hardware and the device driver for it, by keeping the hardware performing I/O at all times (no setup latency between requests by allowing multiple I/O requests to be queued in hardware). Note this is a character device, not a filesystem. I implemented aio_read() and aio_write() on my character device interface, but it's never been called; read() and write() is called instead. >From "Understanding the Linux kernel, 3rd edition" I read that glibc indeed implements aio_read() and friends itself, not through the kernel AIO syscalls. <Quote> Essentially, the aio_read( ) or aio_write( ) library function clones the current process and lets the child invoke the synchronous read( ) or write( ) system calls; However, this "poor man's" version of the POSIX functions is significantly slower than a version that uses a kernel-level implementation of asynchronous I/O. <End Quote> I am looking for a rich man's way to use the kernel functionality; essentially I want my drivers aio_read and aio_write ops to be called. Regards, -- Leon
