Re: Logging disk access in block level?

[lusec001@xxxxxxxxxx]

> I want to save the access log of disk in block level.
> The number of block in disk and the I/O type (R/W) of
> the request are needed for me.
>
> What should I modify to save the log? In block cache
> code? or EXT{2,3}?

I don't understand so well the question. But, if the information that you
want is the blocks requested and the type of operation, you need to trace
the __make_request function
[http://lxr.free-electrons.com/source/block/ll_rw_blk.c#2905] and print
the values obtained with the bio paramter
[http://lxr.free-electrons.com/source/include/linux/bio.h#072]. You could
do all this with kprobes.

Regards,

Luis.


--
Kernelnewbies: Help each other learn about the Linux kernel.
Archive:       http://mail.nl.linux.org/kernelnewbies/
FAQ:           http://kernelnewbies.org/faq/