When I'm trying delete some of the old eaccelerator files it gives me following errors

rm: cannot remove `/tmp/eaccelerator/7/2/eaccelerator-0502.02065984': Read-only file system

What can I do it fix it?

Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2             226G  127G   88G  60% /
/dev/sdc1             227G  102G  114G  48% /disk1
/dev/sda1              99M   18M   77M  19% /boot
tmpfs                 4.0G     0  4.0G   0% /dev/shm
/dev/sdb1             459G  182G  255G  42% /home4
/usr/tmpDSK           485M  325M  135M  71% /tmp

That's my output from the server.

Also what commands can I use to unmount and mount it? And should I do it while my web server is running?