I was doing some checks on a server and found an imap process running at 100%, kill -9 was unable to kill it.
hammer ~ # lsof -p 1918 COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME imap 1918 vpopmail cwd DIR 8,2 96 539699 /var/vpopmail/domains/maxpersuasion.com/kec imap 1918 vpopmail rtd DIR 8,2 856 2 / imap 1918 vpopmail txt REG 8,2 851832 3646578 /usr/libexec/dovecot/imap imap 1918 vpopmail mem REG 8,2 1330888 2752698 /lib64/libc-2.8.so imap 1918 vpopmail mem REG 8,2 14520 2753738 /lib64/libdl-2.8.so imap 1918 vpopmail mem REG 8,2 114960 2753800 /lib64/ld-2.8.so imap 1918 vpopmail 2w FIFO 0,5 0t0 574015 pipe imap 1918 vpopmail 6u 0000 0,6 0 10 anon_inode
strace & gdb can't seem to attach to the process.
The process was started 2 days ago.
It is dovecot 1.1.6