I have problem with my server. Server is running centos 6 (CloudLinux Server release 6.2). uname -a = 2.6.32-320.4.1.lve1.1.4.el6.x86_64 That is a kvm guest. On host is debian 6.

If i run command ps aux, it stuck on random process (shows some processes only), top command is working fine. htop doesn't work too (black screen).

top - 12:11:51 up 34 min,  1 user,  load average: 4.26, 6.71, 16.15
Tasks: 201 total,   7 running, 192 sleeping,   0 stopped,   2 zombie
Cpu(s):  7.9%us,  2.8%sy,  0.0%ni, 87.5%id,  1.6%wa,  0.0%hi,  0.2%si,  0.0%st
Mem:   9862044k total,  2359484k used,  7502560k free,   171720k buffers
Swap: 10485720k total,        0k used, 10485720k free,  1336872k cached

server has one Intel(R) Xeon(R) CPU E5606 @ 2.13GHz,

free -m

             total       used       free     shared    buffers     cached
Mem:          9630       2336       7293          0        170       1324
-/+ buffers/cache:        841       8789
Swap:        10239          0      10239

php -v

PHP 5.3.19 (cli) (built: Nov 28 2012 10:03:07)
Copyright (c) 1997-2012 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2012 Zend Technologies
    with the ionCube PHP Loader v4.2.2, Copyright (c) 2002-2012, by ionCube Ltd., and
    with Zend Guard Loader v3.3, Copyright (c) 1998-2010, by Zend Technologies
    with Suhosin v0.9.33, Copyright (c) 2007-2012, by SektionEins GmbH

mysql Server version: 5.1.63-cll

php -i

disable_functions => apache_child_terminate, apache_setenv, define_syslog_variables, escapeshellarg, escapeshellcmd, eval, exec, fp, fput, ftp_connect, ftp_e
xec, ftp_get, ftp_login, ftp_nb_fput, ftp_put, ftp_raw, ftp_rawlist, highlight_file, ini_alter, ini_get_all, ini_restore, inject_code, openlog, passthru, php
_uname, phpAds_remoteInfo, phpAds_XmlRpc, phpAds_xmlrpcDecode, phpAds_xmlrpcEncode, popen, posix_getpwuid, posix_kill, posix_mkfifo, posix_setpgid, posix_set
sid, posix_setuid, posix_setuid, posix_uname, proc_close, proc_get_status, proc_nice, proc_open, proc_terminate, shell_exec, syslog, system, xmlrpc_entity_de
code, xmlrpc_server_create, putenv, show_source,mail => apache_child_terminate, apache_setenv, define_syslog_variables, escapeshellarg, escapeshellcmd, eval,
 exec, fp, fput, ftp_connect, ftp_exec, ftp_get, ftp_login, ftp_nb_fput, ftp_put, ftp_raw, ftp_rawlist, highlight_file, ini_alter, ini_get_all, ini_restore,
inject_code, openlog, passthru, php_uname, phpAds_remoteInfo, phpAds_XmlRpc, phpAds_xmlrpcDecode, phpAds_xmlrpcEncode, popen, posix_getpwuid, posix_kill, pos
ix_mkfifo, posix_setpgid, posix_setsid, posix_setuid, posix_setuid, posix_uname, proc_close, proc_get_status, proc_nice, proc_open, proc_terminate, shell_exe
c, syslog, system, xmlrpc_entity_decode, xmlrpc_server_create, putenv, show_source,mail
...
suhosin.executor.disable_eval => Off => Off
suhosin.executor.eval.blacklist => include,include_once,require,require_once,curl_init,fpassthru,base64_encode,base64_decode,mail,exec,system,proc_open,leak,
syslog,pfsockopen,shell_exec,ini_restore,symlink,stream_socket_server,proc_nice,popen,proc_get_status,dl, pcntl_exec, pcntl_fork, pcntl_signal,pcntl_waitpid,
 pcntl_wexitstatus, pcntl_wifexited, pcntl_wifsignaled,pcntl_wifstopped, pcntl_wstopsig, pcntl_wtermsig, socket_accept,socket_bind, socket_connect, socket_cr
eate, socket_create_listen,socket_create_pair,link,register_shutdown_function,register_tick_function,gzinflate => include,include_once,require,require_once,c
url_init,fpassthru,base64_encode,base64_decode,mail,exec,system,proc_open,leak,syslog,pfsockopen,shell_exec,ini_restore,symlink,stream_socket_server,proc_nic
e,popen,proc_get_status,dl, pcntl_exec, pcntl_fork, pcntl_signal,pcntl_waitpid, pcntl_wexitstatus, pcntl_wifexited, pcntl_wifsignaled,pcntl_wifstopped, pcntl
_wstopsig, pcntl_wtermsig, socket_accept,socket_bind, socket_connect, socket_create, socket_create_listen,socket_create_pair,link,register_shutdown_function,
register_tick_function,gzinflate

Sometimes i cannot kill httpd process. I run kill -9 PID even several times, and nothing happens. php runs via suphp. I learned somewhere that it can be trojan. I ran strace ps aux and it stops on open("/proc/PID/cmdline", O_RDONLY)

If i reboot server, problem is gone but after some time it is back again .. :(

Thanks.