[Solved] Slow Unmouting USB

[Soapm]

I am having a problem if I don't properly unmount my USB drive before removing it from my server. However, it seems to take upward of 15 minutes (I may be exaggerating) when I do "unmount /movies".

Googling I found this https://lonesysadmin.net/2013/12/22/bet ... rty_ratio/ article basically saying data is sitting in ram that isn't being written to the drive until I try to unmount the drive. And it's writing that data that takes all the time.

In addition to the above article, I found a few site that talk about different settings to adjust to minimize this effect, but none of it is Debian specific and I'm afraid of messing up my good running server.

What do you guys think about this advice I found on a Ubuntu site https://askubuntu.com/questions/410136/ ... es-forever

Workaround: enter a shell root (do that with care --- you are now root for every command)

sudo -i

and issue:

echo $((16*1024*1024)) > /proc/sys/vm/dirty_background_bytes
echo $((48*1024*1024)) > /proc/sys/vm/dirty_bytes

If it works, you can add the two lines above to your /etc/rc.local file.

Again, I'm just afraid of doing more harm than good since I really have no knowledge in this area. I'm just trying to reduce the time it takes the drive to unmount so I can remove it from the server.

My server has 8 gigs of Ram and an Intel G3258 Processor...

[Head_on_a_Stick]

I am having a problem if I don't properly unmount my USB drive before removing it from my server. However, it seems to take upward of 15 minutes (I may be exaggerating) when I do "unmount /movies".

I hope that was a typo

Try:

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sync ; umount -R /movies && echo Done!

But do not remove the device until you see "Done!" appear in the terminal.

What do you guys think about this advice I found on a Ubuntu site

[Segfault]

No need to alter systemwide settings, just use sync option to mount this device. Then again, if your server is networked why not use other methods to share your files, like firing up webfs (very light http server). Using USB sticks smells like planting viruses nowadays, they can be used to boot and troubleshoot but I personally have no other use for them.

[Soapm]

No need to alter systemwide settings, just use sync option to mount this device. Then again, if your server is networked why not use other methods to share your files, like firing up webfs (very light http server). Using USB sticks smells like planting viruses nowadays, they can be used to boot and troubleshoot but I personally have no other use for them.

I have two USB sticks I use, one for music in the car and the other for movies at the office. I rsync both to folders on my video server as a means of keeping them current and refreshed.

I have a plex server to stream but Comcast has me limited to 1tb/month and my daughter has Netflix. Need I say more?

this is the mount line from my fstab file with user/group ID nobody/nogroup; It mounts via Samba so I can manipulate the files from either of my windows machines if necessary.

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UUID="7488-0B18"     /music        ntfs-3g  defaults,noatime,umask=000,dmask=000,fmask=000,uid=65534,gid=65534        0 0

Do I just add sync like this?

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UUID="7488-0B18"     /music        ntfs-3g  sync,defaults,noatime,umask=000,dmask=000,fmask=000,uid=65534,gid=65534        0 0

[Soapm]

I am having a problem if I don't properly unmount my USB drive before removing it from my server. However, it seems to take upward of 15 minutes (I may be exaggerating) when I do "unmount /movies".

I hope that was a typo

It might be a slight exaggeration but it seems like forever when the wife is blowing the horn or you're running late for a meeting at the office.

Glad I didn't make the changes but I realize that was part of why my usb stick wouldn't plan in the car, I was pulling it out the server without unmouting it first.

I added your line to my bash file so I get the "done" anytime I unmount something...

[Segfault]

TBH I do not think sync as mount option is going to speed up anything, it probably is even not good for flash memory. You could copy like this:

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cp myfile && sync

This will copy and write immediately. How fast - it depends on your USB port and stick speed. Don't expect wonders.

[Soapm]

TBH I do not think sync as mount option is going to speed up anything, it probably is even not good for flash memory. You could copy like this:

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cp myfile && sync

This will copy and write immediately. How fast - it depends on your USB port and stick speed. Don't expect wonders.

I use rsync to put the files on the stick, this is the command in my bash file which excludes that annoying "System Volume" folder windows adds to my disk. I guess I can remove that part now that it's been formatted in the debian server.

But are you suggesting something like this?

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alias syncm='rsync -arv --exclude 'System*' /video/Church/Church\ Movies/ /movies/ --delete-after'

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alias syncm='rsync -arv --sync /video/Church/Church\ Movies/ /movies/ --delete-after'

Or how would I include sync with this command...

PS... How about this?

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alias syncm='rsync -arv --exclude 'System*' /video/Church/Church\ Movies/ /movies/ --delete-after' && sync

[Segfault]

'sync' is standalone command, see 'man sync'. (Not sure if rsync has similar option.) And don't confuse it with sync mount option, it is not the same thing.

[Soapm]

You were answering while I was editing, how about this?

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alias syncm='rsync -arv --exclude 'System*' /video/Church/Church\ Movies/ /movies/ --delete-after && sync'

[Segfault]

Yea, try it out. Note, umount does the same thing, it executes sync before it unmounts.

[Soapm]

Yea, try it out. Note, umount does the same thing, it executes sync before it unmounts.

thanks for all the help, I don't have a way to test it until I add or remove more movies but I don't get any errors when I run the command.

Thanks again...

As a side note, I had a made an alias called sync for syncing my music so each time I would run this command I'd see my music syncing. This allowed me to see the error in my ways so now I have "syncmus" and "syncmov". I just hope I can remember my new commands, I am a person to whom old habits die real hard.

[Segfault]

sync as alias is maybe not the best since it will mask the real sync command. I'd use something unique. Otherwise you may need to call it using full path, like this '/bin/sync'.

[Soapm]

sync as alias is maybe not the best since it will mask the real sync command. I'd use something unique. Otherwise you may need to call it using full path, like this '/bin/sync'.

Yup, that was the funny part, i didn't realize I had a sync command so didn't realize I had masked it.

But we got her now... Thanks again.

[Soapm]

I loaded 4 movies just for kicks and grins, I think this worked because now it takes forever at the end of the rsync command.

But at least it unmounts quickly so that's a plus...