logging for hotfiles.

[Steve Flynn]

On Sat, Feb 20, 2010 at 5:35 AM, MirJafar Ali <mirjafarali at gmail.com> wrote:
> hello,
>
> I am interesting in collecting data for file system analysis. I use Ubuntu
> and it has ext3 file system. Does filesystem keep
> track of how many times simple file operations were performed ( along with
> the timestamp ) i.e. open, read and write ?

Not out of the box as far as I'm aware. To track this kind of thing,
you're going to need some hooks into the ext2/3/4 disk subsystem code
to keep track of this data, Certainly, it shouldn't be too onerous to
write a jiffie value out somewhere but be in mind that your code is
going to have a performance impact on all disk i/o. Plus you're going
to get your hands very dirty with code that could quite easily trash
your filesystem.


> With the timestamp and frequency, I want to study the behaviour of hot files
> and their layout on disks.

Really, you should be asking this type of question on the ext2/3/4
mailing lists. The developers there are intimately familiar with the
action under the hood of all of the ext disk formats. They will either
point you straight to where you should be hooking your code in or what
flags you need to switch on to activate some debugging and produce
something suitable for your studies.

-- 
Steve
When one person suffers from a delusion it is insanity. When many
people suffer from a delusion it is called religion.

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