Can't delete php sessions

Question

I have read dozens of posts on his subject, yet cannot find a solution that works for me.

I have a user account. PHP sessions for that account are stored in

/home/user/tmp

Apache start tossing errors that i can't open sessions because the device is full.

df and df -i both show me that the device has plenty of space.

So I look to he /home/user/tmp directory. It shows the size of the directory is 901MB.

I wan to delete the session files from the directory.

I have tried

rm -rf /home/user/tmp/sess_*

I let his run for over an hour then used cntr+C to kill the command. The directory still says 901 MB.

I have rebooted the system, the directory still shows at 901MB.

I have tried

find /home/*/tmp -type f -name 'sess_*' -ctime +5 -delete

Just like with rm -rf I let the command run for over an hour and killed it.

The directory still shows 901MB.

I am issuing these commands as root user. I am using ubuntu 16.04. This is a server so only command line options will work.

What can I do to remove these session files?

Answer 1

Often you can't delete session files even with command like sudo rm -rf /var/lib/php/sessions/* because a path name expansion occurs BEFORE the sudo (https://serverfault.com/a/851261/591003).

You can try another command like sudo sh -c "rm -rf /var/lib/php/sessions/*" but if you have tons of files you'll get an answer that rm: Argument list too long because the list of session files is usually very huge (up to millions of files).

I propose a really simple way:

1. Create a new folder sessions_new: mkdir /var/lib/php/sessions_new
2. Set the same permissions as for old sessions directory: sudo chmod --reference=sessions sessions_new
3. Do the same with ownership: sudo chown --reference=sessions sessions_new
4. Kill it! sudo rm -rf /var/lib/php/sessions
5. You don't need to wait a result for a long time. You can check it immediately in a new terminal window by sudo find /var/lib/php/sessions/. -type f|wc -l. This command counts the number of files inside your sessions folder. Run it two times. If the second time you run the command, you get a lower number than the first time, then the process is going in the right direction.
6. Wait for a long time :P
7. When process has finished just rename the session_new directory: mv /var/lib/php/sessions_new /var/lib/php/sessions

Answer 2

If it's a lot of small files, deleting can take some significant time. Let it run until it finishes. It should eventually finish.

I did a quick test on my system, and deleting 100k empty files on a SSD disk with ext4 took 1.14 seconds. If you have tens of millions of files, it may take a good while.

Answer 3

I think Dzmitry Kulahin's solution works, but in my case I ran out of space so I couldn't create the new "sessions_new" directory. I solved using command line php in interactive mode:

sudo php -a

please note that you must use sudo, otherwise subsequent commands have no privileges to operate.

Write this sequence on a single line, it is necessary to write it on a single line because in interactive mode, each press of the enter key immediately executes the command:

$listfile = scandir("/var/lib/php/sessions/");
foreach ($listfile as $file) {
    if (!is_dir("/var/lib/php/sessions/".$file)) {
        unlink("/var/lib/php/sessions/".$file);
    }
}

Press the enter key and the files start deleting.

You can monitor the cancellation by opening another terminal and typing:

sudo find /var/lib/php/sessions/. -type f|wc -l

It will show you the number of files in the directory, repeating this the command several times you will see the number go down as the files are deleted.