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Apparently, Fedora implements the most complex partition scheme imaginable...

/proc on /proc type proc (rw,relatime)
/sys on /sys type sysfs (rw,relatime,seclabel)
udev on /dev type devtmpfs (rw,nosuid,relatime,seclabel,size=1488932k,nr_inodes=209830,mode=755)
devpts on /dev/pts type devpts (rw,relatime,seclabel,gid=5,mode=620,ptmxmode=000)
tmpfs on /dev/shm type tmpfs (rw,relatime,seclabel)
tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,seclabel,mode=755)
/dev/mapper/vg_x200s-lv_root on / type ext4 (rw,relatime,seclabel,barrier=1,data=ordered)
selinuxfs on /selinux type selinuxfs (rw,relatime)
tmpfs on /sys/fs/cgroup type tmpfs (rw,nosuid,nodev,noexec,relatime,seclabel,mode=755)
cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/ns type cgroup (rw,nosuid,nodev,noexec,relatime,ns)
cgroup on /sys/fs/cgroup/cpu type cgroup (rw,nosuid,nodev,noexec,relatime,cpu)
cgroup on /sys/fs/cgroup/cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpuacct)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/net_cls type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls)
cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)
systemd-1 on /sys/kernel/debug type autofs (rw,relatime,fd=27,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=28,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)
systemd-1 on /dev/mqueue type autofs (rw,relatime,fd=29,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)
systemd-1 on /dev/hugepages type autofs (rw,relatime,fd=30,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)
systemd-1 on /sys/kernel/security type autofs (rw,relatime,fd=31,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)
tmpfs on /var/run type tmpfs (rw,nosuid,nodev,noexec,relatime,seclabel,mode=755)
tmpfs on /var/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,seclabel,mode=755)
tmpfs on /media type tmpfs (rw,nosuid,nodev,noexec,relatime,rootcontext=system_u:object_r:mnt_t:s0,seclabel,mode=755)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,seclabel)
mqueue on /dev/mqueue type mqueue (rw,relatime,seclabel)
/dev/sda1 on /boot type ext4 (rw,relatime,seclabel,barrier=1,data=ordered)
/dev/mapper/vg_x200s-lv_home on /home type ext4 (rw,relatime,seclabel,barrier=1,data=ordered)
fusectl on /sys/fs/fuse/connections type fusectl (rw,relatime)
gvfs-fuse-daemon on /home/ecarroll/.gvfs type fuse.gvfs-fuse-daemon (rw,nosuid,nodev,relatime,user_id=500,group_id=500)

Compare that for amusement to an Ubuntu install...

/dev/sda6 on / type xfs (rw,noatime,nodiratime)
proc on /proc type proc (rw)
none on /sys type sysfs (rw,noexec,nosuid,nodev)
none on /sys/fs/fuse/connections type fusectl (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /sys/kernel/security type securityfs (rw)
none on /dev type devtmpfs (rw,mode=0755)
none on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)
none on /dev/shm type tmpfs (rw,nosuid,nodev)
none on /var/run type tmpfs (rw,nosuid,mode=0755)
none on /var/lock type tmpfs (rw,noexec,nosuid,nodev)
none on /lib/init/rw type tmpfs (rw,nosuid,mode=0755)
none on /var/lib/ureadahead/debugfs type debugfs (rw,relatime)
/dev/sda1 on /boot type ext3 (rw)

What is a cgroup and why are there are so many entries for things like /dev/mapper?

Is this some esoteric LVS configuration, and if so... Where is it documented?

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2 Answers

/proc on /proc type proc (rw,relatime)

procfs provides information about running processes and other system information. It has been present in Unix-like operating systems since 1984.

/sys on /sys type sysfs (rw,relatime,seclabel)

sysfs is a feature of the 2.6 series of the Linux kernel that provides information about drivers and devices. Before it existed each driver had its own convoluted API to access and change information and configurable options.

udev on /dev type devtmpfs (rw,nosuid,relatime,seclabel,size=1488932k,nr_inodes=209830,mode=755)

udev replaces the earlier devfs and in concert with the kernel allows devices like external drives, printers, etc. to be connected and disconnected at will.

devpts on /dev/pts type devpts (rw,relatime,seclabel,gid=5,mode=620,ptmxmode=000)

/dev/pts houses virtual terminals. A device is created in that directory when you open a terminal window in desktop environments like GNOME and KDE.

tmpfs on /dev/shm type tmpfs (rw,relatime,seclabel)

shm stands for shared memory. It allows programs to share data by using what appears to be a file on disk, but is actually stored in memory. tmpfs allows any arbitrary portion of the file system to be stored in memory instead of disk.

tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,seclabel,mode=755)

/run replaces /var/run. Many Linux users partition their drives such that /var is on a separate partition, and thus it's unavailable to software that runs during early boot, such as initrds like Fedora's dracut, systemd, and udev. Previously, they did crazy things like make hidden directories in /dev to store data that should have been stored in /var/run.

/dev/mapper/vg_x200s-lv_root on / type ext4 (rw,relatime,seclabel,barrier=1,data=ordered)

This is your root directory partition /. By default Fedora uses LVM2, which allows you to resize, create, and span volumes across multiple partitions or disks easily. A new filesystem called btrfs is in development that will be able to accomplish this much more simply, along with a host of other features.

selinuxfs on /selinux type selinuxfs (rw,relatime)

Security-Enhanced Linux is an extension to the Linux kernel created by the U.S. National Security Agency to implement Mandatory Access Control, and has now been rolled into the official Linux kernel. It predates sysfs so it exists out of /sys for historical reasons, but Fedora plans to move it into /sys for Fedora 16.

tmpfs on /sys/fs/cgroup type tmpfs (rw,nosuid,nodev,noexec,relatime,seclabel,mode=755)
cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/ns type cgroup (rw,nosuid,nodev,noexec,relatime,ns)
cgroup on /sys/fs/cgroup/cpu type cgroup (rw,nosuid,nodev,noexec,relatime,cpu)
cgroup on /sys/fs/cgroup/cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpuacct)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/net_cls type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls)
cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)

cgroups are a feature of the Linux kernel that allows processes to be split into groups and have resources like CPU time and disk I/O. systemd, the new init system that replaces Upstart and sysvinit before it uses them extensively to do a lot of cool stuff.

systemd-1 on /sys/kernel/debug type autofs (rw,relatime,fd=27,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)

debugfs provides debugging information for Linux kernel developers. systemd and autofs now handle a lot of drive mapping, so all of the systemd-1/autofs mount points aren't actually mounted until they are used. However, the mount point must be registered so that the kernel knows to mount the filesystem when it is used.

systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=28,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)

binfmt_misc is a location centralized across distributions to store information about alternate binary formats and software that can run them, such as the Windows Portable Executable format ran by WINE.

systemd-1 on /dev/mqueue type autofs (rw,relatime,fd=29,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)
systemd-1 on /dev/hugepages type autofs (rw,relatime,fd=30,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)

These automount points have a corresponding real mount point described later.

systemd-1 on /sys/kernel/security type autofs (rw,relatime,fd=31,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)

securityfs provides a access point to manage security modules for Linux like Ubuntu's AppArmor.

tmpfs on /var/run type tmpfs (rw,nosuid,nodev,noexec,relatime,seclabel,mode=755)

This is a bind mount to /run. It cannot be a symlink yet for compatibility reasons, although this is planned for Fedora 16.

tmpfs on /var/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,seclabel,mode=755)

This is a bind mount to /run/lock. It also cannot be a symlink yet.

tmpfs on /media type tmpfs (rw,nosuid,nodev,noexec,relatime,rootcontext=system_u:object_r:mnt_t:s0,seclabel,mode=755)

/media stores mount points to external devices and media like USB drives and DVDs.

hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,seclabel)

hugepages allows software to use large chunks of memory more efficiently.

mqueue on /dev/mqueue type mqueue (rw,relatime,seclabel)

This provides support on Linux for POSIX message queues.

/dev/sda1 on /boot type ext4 (rw,relatime,seclabel,barrier=1,data=ordered)

This is your /boot partition, which stores the GRUB bootloader and compressed copies of all the Linux kernels installed on your system.

/dev/mapper/vg_x200s-lv_home on /home type ext4 (rw,relatime,seclabel,barrier=1,data=ordered)

This is your /home partition, also on an LVM2 volume.

fusectl on /sys/fs/fuse/connections type fusectl (rw,relatime)

FUSE stands for Filesystem in Userspace, which allows for filesystem drivers to be written as normal programs, instead of drivers built-in to the Linux kernel.

gvfs-fuse-daemon on /home/ecarroll/.gvfs type fuse.gvfs-fuse-daemon (rw,nosuid,nodev,relatime,user_id=500,group_id=500)

This is used by GNOME for filesystems mounted through the Nautilus file manager.

As Ignacio Vazquez-Abrams alludes to: Ubuntu's goal as a project is to create an easy-to-use Linux distribution. Fedora's goal is to provide the latest Linux technologies as fast as possible.

Additionally, you should always read the release notes when upgrading or installing a new distribution/version. This version's in particular would have explained a good chunk of this.

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Fedora has never hidden the fact that they have/use cutting edge features.

cgroups

systemd

LVM

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