Comment #1 on issue 174 by ilnarb: Memcached process hangs under load ~ 30
mb/s
http://code.google.com/p/memcached/issues/detail?id=174
it's not memcached problem.
it's problem in packet processing.
usual net crads like intel e1000 will process load in one cpu core/
that's why your one cpu loaded by kernel 100%, perhaps, you see ksoftirqd
in the top.
try to update RHEL up to 2.6.31 (RHEL 6), it contains network multitasking
(since 2.6.29)
better way is to use igb network card. it allows to create multiple queues
