Disk defragmenter in Linux

[Guy Fraser]

On Thu, 2005-29-12 at 01:21 +0800, John Summerfied wrote:
> Guy Fraser wrote:
> > On Tue, 2005-27-12 at 19:46 -0800, Peter Gordon wrote:
> > 
> >>On Tue, 2005-12-27 at 17:27 -0700, Guy Fraser wrote:
> >>
> >>>Stuffing a lot of files into a directory is a bad practice,
> >>>and Red Hat is well known for it. Check /usr/bin, /etc and 
> >>>a few others. Many of the files would [normally] be located 
> >>>under /usr/local.
> >>
> >>Pardon my probable misunderstanding, but isn't this the whole idea
> >>of the standard filesystem layout for Unix/Unix-like operating systems?
> >>
> >>I.e., if it's not installed through the system package manager, it has
> >>its tree of /lib, /sbin, /bin, /man, /share, etc under /usr/local;
> >>whereas if it *is* installed through the system packaging, it has its
> >>own /lib, /sbin, /bin, /share, /man, etc layout tree under / or /usr,
> >>depending on various factors like partitioning or network-mounting /usr,
> >>etc.
> > 
> > 
> > That is how Red Hat and it's offshoots work.
> > 
> > It can be a contentious issue, exactly where to put 
> > non base system files. Sun Microsystems used to prefer 
> > /opt but almost everyone else uses /usr/local for most 
> > add on software. But it is well understood that :
> > 
> > 	/bin, /sbin and /lib are for 
> > single user base system commands and their required libraries.
> That's not quite the case. Check the facts at http://www.pathname.com/ 
> (and fall in love with Enya while you're there).

That is from January 2004, and appears to be Red Hat centric.
I learnt about file system hierarchy in the 1980's. Just because 
someone claims to be in charge of some kind of official web page 
on file system hierarchy does mean it is the official 
recommendations for all distributions and Unix variants.

See:
http://www.debian.org/doc/packaging-manuals/fhs/
http://www.isu.edu/departments/comcom/unix/workshop/fstour.html
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/dirstructure.html

Recommended best practises have been around much longer than 
Linux. The first distributions of Linux favoured the classic 
best practises, and many distributions still do.

There are many good reasons for the classic hierarchy and 
a lot of study and research went into it's development. Many 
of the reasons still hold, but most are too complex to deal 
with in this forum. Some things to consider are frequency of 
modification, accessability, ownership and type or purpose 
of the file. Other things to remember are that large numbers 
of files in a directory and large variations in the file sizes 
on a partition can have detrimental effects on performance 
and more specifically on this topic, can be the cause of 
fragmentation.

If you can take one fact from this conversation, it is that 
the system you use depends on how you prefer to manage your 
system. There may be a standard that Red Hat and it's adopters 
prefer, but there is no official standard that must be followed
as is demonstrated by differences in Unix variants and Linux 
distributions.