And look, the sunset on another module.
A module where I really hope you've got a lot out of it,
as we've learned how we can go through and monitor and tune the
performance of our disks and block devices.
So the first thing we were trying to understand is the idea of IOPS,
our io's per second, and that can be read or write operations.
We can start seeing the performance of our devices,
and we can see it aggregated using the ‑b option to sar.
We can also go through and look at individual
device files by using the ‑d option.
We introduced as well, although it's not related just to our block devices,
the option ‑f, where we want to see our activity from a different day,
we can open up a different file.
By default, it will be the current day's file,
but we can browse through to var, log,
and SYSTAT and look for the correct day's file.
The ioping or ioping, however you want to say it,
the ioping utility is used though,
so we can measure in real time the performance of a disk or file system.
And we've seen that the file system is generally going to give us slower access.
Whereas we go to a raw device, we're probably going to get faster access.
And we highlighted the need of when we're looking at our swap to
make sure that it's not placed on a file system,
but in a raw disk device such as a disk or a partition.
We also might find that fragmentation of our file system slows
down access to data because we're then going to have to pick it
up from multiple areas of our disk.
We might find by defragmenting our file system,
we then push all of the blocks of related files back together so
that we can access them from contiguous blocks.
Finally, we took a look at mount options,
and we're seeing how we could read our mount options by going through and
look at their current mount options using the mount command.
But we could then go through and investigate other mount
options and set them either in our fstab file,
or we could go through and set them in real time from the command line with ‑o,
and remount is included as our options.
We also saw that the man page, our manual pages,
will provide extensive documentation for our file system options,
and we introduced to you the ext4 f man page.
But that's it. We are done and dusted with managing our block devices.
We're going to be moving on though, to look at how we can
troubleshoot user access to things like quotas,
permissions, passwords,
the normal type of issues that we're likely to have when we're managing users on our systems.