メモリ消費テスト

Here's 2 commands you can run on a test system that will consume a significant 
amount of memory without installing any additional software.

host:~ # dd if=/dev/zero of=/dev/null bs=1T
where bs (block size) is around the size of your memory commit limit (cat 
/proc/meminfo and note CommitLimit). Of course you can use any value you like 
depending on how much memory you want to use. If you specify too large of a 
value it will fail to allocate the buffer.

Also you can just tell bash to consume as much memory as possible with a 
command line like this:
host:~ # A=0; while true; do A="$A$A"; done
-bash: xrealloc: cannot reallocate 18446744071562068096 bytes (0 bytes 
allocated)
It will keep running until it consumes so much memory it fails to allocate 
anymore for its internal buffer.