--- Jan Hudec <bulb@ucw.cz> wrote: > On Sun, Feb 01, 2004 at 15:52:01 -0800, Carl Spalletta wrote: > > In a recent O'Reilly Press book "Java NIO" by R. Hitchens... > > FIRST ALTERNATIVE: read() syscall > > Nonblocking read.. > There is no non-blocking read from disk! > There is only an aio_read, which is a different syscall. You are correct - although I am discussing how the system uses the pagecache which is by definition from memory. > the mechanizm for loading pages is the > same for read as for page-fault. I am not sure how a simple read() of a regular file in a disk based filesystem can generate a page fault - the read goes to disk to get the info to copy to the userspace buffer, while a page_fault on an uncached page of an mmapped file uses the readpage() method. Is this incorrect? Can you explain further? ===== Carl Spalletta -- They have an engine called the Press, whereby the people are deceived. __________________________________ Do you Yahoo!? Yahoo! SiteBuilder - Free web site building tool. Try it! http://webhosting.yahoo.com/ps/sb/ -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
