build agent memory requirements

I'm trying to setup ubuntu vps as a build agent. With default settings teamcity agent consumes about 900mb of RAM (reducing XmX and -XX:MaxPermSize can shrink it into 600mb). VPS has only 1gb of RAM, so builds constantly run out of memory. Is this ok? Can I use some low cost hardware for build agent?

Teamcity version is 7.1.3 (build 24266)
On build agent:
root@ubuntu-kiam:~# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 12.04.2 LTS
Release:        12.04
Codename:       precise

root@ubuntu-kiam:~# java -version
java version "1.7.0_40"
Java(TM) SE Runtime Environment (build 1.7.0_40-b43)
Java HotSpot(TM) Client VM (build 24.0-b56, mixed mode)

root@ubuntu-kiam:~# top
Tasks:  25 total,   1 running,  24 sleeping,   0 stopped,   0 zombie
Cpu(s):  0.0%us,  0.7%sy,  0.0%ni, 99.3%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:   1048576k total,   917912k used,   130664k free,        0k buffers
Swap:   524288k total,        0k used,   524288k free,   917912k cached

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND                                                                 
    1 root      20   0 24164 2124 1360 S  0.0  0.2   0:00.04 init                                                                    
    2 root      20   0     0    0    0 S  0.0  0.0   0:00.00 kthreadd/17121                                                          
    3 root      20   0     0    0    0 S  0.0  0.0   0:00.00 khelper/17121                                                           
   88 root      20   0 17188  740  516 S  0.0  0.1   0:00.00 upstart-udev-br                                                         
  112 root      20   0 21528 1352  784 S  0.0  0.1   0:00.00 udevd                                                                   
  113 messageb  20   0 23772  792  520 S  0.0  0.1   0:00.00 dbus-daemon                                                             
  147 root      20   0 21524  940  364 S  0.0  0.1   0:00.00 udevd                                                                   
  148 root      20   0 21524  940  364 S  0.0  0.1   0:00.00 udevd                                                                   
  197 root      20   0 15144  548  348 S  0.0  0.1   0:00.00 upstart-socket-                                                         
  295 root      20   0 49988 2768 2172 S  0.0  0.3   0:00.00 sshd                                                                    
  338 root      20   0 19068 1016  780 S  0.0  0.1   0:00.00 cron                                                                    
  339 root      20   0 14924 1084  892 S  0.0  0.1   0:00.00 xinetd                                                                  
  386 syslog    20   0 12708  788  604 S  0.0  0.1   0:00.01 syslogd                                                                 
  424 root      20   0 78696 1096  392 S  0.0  0.1   0:00.00 saslauthd                                                               
  426 root      20   0 78696  744   40 S  0.0  0.1   0:00.00 saslauthd                                                               
  495 root      20   0 89136 2264  564 S  0.0  0.2   0:00.22 sendmail-mta                                                            
  565 root      20   0 69728 2860 1256 S  0.0  0.3   0:00.20 apache2                                                                 
  568 www-data  20   0 69752 2168  552 S  0.0  0.2   0:00.00 apache2                                                                 
9286 root      20   0 73392 3576 2768 S  0.0  0.3   0:00.04 sshd                                                                    
9298 root      20   0 18084 2056 1504 S  0.0  0.2   0:00.00 bash                                                                    
15732 root      20   0 73392 3592 2768 S  0.0  0.3   0:00.02 sshd                                                                    
15744 root      20   0 18104 2104 1532 S  0.0  0.2   0:00.00 bash                                                                    
15822 root      20   0  376m  18m 6140 S  0.0  1.8   0:00.20 java                                                                    
15834 root      20   0  524m  58m  10m S  0.0  5.7   0:08.47 java                                                                    
15873 root      20   0 17164 1308 1052 R  0.0  0.1   0:00.00 top