Werner Fischer <devlists@xxxxxxxx> writes: > Dear fio users and developers, > > I have a question regarding the Linux I/O stack (not directly regarding > fio, but I think fio user's and developers have a lot of knowledge > here): > > I'm trying to better understand the different layers of the Linux I/O > stack and how they play together. So I have started a diagram showing > the different layers of the I/O stack: > http://www.thomas-krenn.com/de/wikiDE/images/0/07/Linux-IO-Stack.png > > Is this diagram correct or are there any errors in there? That's a nice diagram. :) A few of things of note: 1) O_DIRECT I/O can bypass the page cache 2) request-based dm targets sit below the I/O scheduler (currently, that just means dm-multipath) 3) the fusion IO device driver can hook itself in where you put it, or also up above the I/O scheduler (based on a module load option). 4) not sure if you want to cover I/O directly to the device (no file system involved) Cheers, Jeff -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
