We have found that the use of APC can artificiallly accelerate PHP's memory usage/requirement for certian scripts/operations, i.e. deserialize() large serialized packets. Most likely a problem within APC.
We recommend that users of APC/PHP that encounter the emalloc() errors to increase memory ceiling for external processes via LiteSpeed admin:
Either server wide:
Server > Security > CGI Resource: memory limits (soft/hard) = 200M / 200M
Or on per extapp basis:
VHost > External Apps > LSAPI App: memory limits (soft/hard) = 200M / 200M
Tweak, increase or decrese the values to fit your enviornment to remove emalloc() errros.