multiple mount points

[muungwana]

/proc is not leaded in in RAM, it is a virtual file system. Its contents doesnt exist anywhere, you read from a file in /proc and the kernel intercepts the read directly and send you data. File sizes of all files in /proc are 0 bytes. All files in /proc takes 0 bytes of space. They do not take any space and hence you are not saying anything by not having /proc.

/proc is not loaded in memory, it is mounted on your root partition because, as i said earlier, it needs to be accessed as if it is a regular folder with regular files but they dont take any space.

Did you restart after you commented out /proc in fstab? can you check to make sure it isnt there and see if the system runs as expected?

I cant think of any program at the moment that checks /proc when they start or when they want to perform a particular operation but there must be out there.

[Yankee]

Did you restart after you commented out /proc in fstab? can you check to make sure it isnt there and see if the system runs as expected?

Info from current /etc/mtab

Code: [Select]

/dev/sda1 / ext4 rw 0 0
none /proc/sys/fs/binfmt_misc binfmt_misc rw 0 0
gvfs-fuse-daemon /home/user/.gvfs fuse.gvfs-fuse-daemon rw,nosuid,nodev,user=pf 0 0
/dev/sdc1 /media/SDHC ext4 rw,nosuid,nodev,uhelper=hal 0 0

I'm running off of the sda1 right now.   The /proc filesystem mounted was done by
the kernel not etc/fstab.   That's supposed to give it quicker access to programs
than if read directly from the hard drive from the /proc directory.

My big disk it doesn't matter, but my flash drives seems to run slower with that
mounted in etc/fstab.   I think that's because it's reading and writing from
RAM to disk and vice-versa with 0 cache to guide it.   Going thru a whole search
process almost.

I'll let it run a few days, but it already has run for at least several months without the
mount in etc/fstab.   Any problems I'll post back before I remount it in etc/fstab.

thx

FF

[muungwana]

can you open the terminal and run "top" command?

does it work as expected?

i ran "top" over strace and below is some of the file access to /proc

open("/proc/stat", O_RDONLY|O_CLOEXEC)  = 3
read(3, "cpu  21554502 77156 2340041 9065"..., 8192) = 4957
close(3)                                = 0
open("/proc/sys/kernel/pid_max", O_RDONLY) = 3
read(3, "32768\n", 24)                  = 6
close(3)                 

stat64("/proc/self/task", {st_mode=S_IFDIR|0555, st_size=0, ...}) = 0
open("/proc", O_RDONLY|O_NONBLOCK|O_LARGEFILE|O_DIRECTORY|O_CLOEXEC) = 3
fcntl64(3, F_GETFD)                     = 0x1 (flags FD_CLOEXEC)
getdents(3, /* 224 entries */, 32768)   = 4196
stat64("/proc/1", {st_mode=S_IFDIR|0555, st_size=0, ...}) = 0
open("/proc/1/stat", O_RDONLY)          = 4
read(4, "1 (init) S 0 1 1 0 -1 4202752 15"..., 1023) = 181
close(4)                                = 0
open("/proc/1/statm", O_RDONLY)         = 4
read(4, "467 14 8 8 0 72 0\n", 1023)    = 18
close(4) 

just to be sure /proc isnt there, run "cat /proc/mounts" and give the output.

"top" command  does a lot of reading in /proc and i wonder how it will behave without it.

I just looked at my program and it would crash on your system .. better go and check againt it

[Yankee]

just to be sure /proc isnt there, run "cat /proc/mounts" and give the output.

"top" command  does a lot of reading in /proc and i wonder how it will behave without it.

I just looked at my program and it would crash on your system .. better go and check againt it

Code: [Select]


[user@localhost ~]$ cat /etc/mtab
/dev/sdb1 / ext4 rw 0 0
none /proc/sys/fs/binfmt_misc binfmt_misc rw 0 0
gvfs-fuse-daemon /home/pf/.gvfs fuse.gvfs-fuse-daemon rw,nosuid,nodev,user=pf 0 0
/dev/sda1 /media/LXDE1 ext4 rw,nosuid,nodev,uhelper=hal 0 0
/dev/sdc1 /media/SDHC ext4 rw,nosuid,nodev,uhelper=hal 0 0

[user@localhost ~]$ cat /proc/mounts
rootfs / rootfs rw 0 0
/dev/root / ext4 rw,relatime,barrier=1,data=ordered 0 0
/dev /dev devtmpfs rw,relatime,size=509716k,nr_inodes=127429,mode=755 0 0
/proc /proc proc rw,relatime 0 0
/sys /sys sysfs rw,relatime 0 0
none /dev/pts devpts rw,relatime,mode=620,ptmxmode=000 0 0
none /dev/shm tmpfs rw,relatime 0 0
fusectl /sys/fs/fuse/connections fusectl rw,relatime 0 0
none /proc/sys/fs/binfmt_misc binfmt_misc rw,relatime 0 0
/proc/bus/usb /proc/bus/usb usbfs rw,relatime,devgid=43,devmode=664 0 0
gvfs-fuse-daemon /home/pf/.gvfs fuse.gvfs-fuse-daemon rw,nosuid,nodev,relatime,user_id=500,group_id=500 0 0
/dev/sda1 /media/LXDE1 ext4 rw,nosuid,nodev,relatime,barrier=1,data=ordered 0 0
/dev/sdc1 /media/SDHC ext4 rw,nosuid,nodev,relatime,barrier=1,data=ordered 0 0

[user@localhost ~]$


Above code is /etc/mtab and cat /proc/mounts

Well it looks like the system is mounting /proc and /dev/pts by default just
as if they were in /etc/fstab.  They're not in my /etc/fstab.   tops runs OK too.
Would explain everything working OK.

THX

FF

[muungwana]

/proc appears to be mounted by "/etc/rc.d/sysinit" script

the chuck of the script that does that is:

if [ ! -e /proc/mounts ]; then
   mount -n -t proc /proc /proc
   mount -n -t sysfs /sys /sys >/dev/null 2>&1
fi

[Just17]

/proc appears to be mounted by "/etc/rc.d/sysinit" script

the chuck of the script that does that is:

if [ ! -e /proc/mounts ]; then
   mount -n -t proc /proc /proc
   mount -n -t sysfs /sys /sys >/dev/null 2>&1
fi

So is the fstab entry redundant? ....  or is it there are a fall-back ?

[Yankee]

/proc appears to be mounted by "/etc/rc.d/sysinit" script

the chuck of the script that does that is:

if [ ! -e /proc/mounts ]; then
   mount -n -t proc /proc /proc
   mount -n -t sysfs /sys /sys >/dev/null 2>&1
fi

So is the fstab entry redundant? ....  or is it there are a fall-back ?

The only line in /etc/fstab that's really needed (not mounted in other scripts)
is the first line to mount the "/" filesystem.    That's what I'm looking at.

regards,

FF