Below is the definition of struct _virDomain from internal.h. I may be missing something big (well, it wouldn't be the first time), but as far as I can see some of these fields are never used, and some are set but can never be read. struct _virDomain { unsigned int magic; /* specific value to check */ OK int uses; /* reference count */ OK virConnectPtr conn; /* pointer back to the connection */ OK char *name; /* the domain external name */ OK char *path; /* the domain internal path */ This field is set in src/xs_internal.c, but nowhere in libvirt does it appear to be read. The only other time it is reference is in hash.c where it is freed if non-NULL. int id; /* the domain ID */ OK int flags; /* extra flags */ Apparently this field could be set to DOMAIN_IS_SHUTDOWN or DOMAIN_IS_DEFINED. However neither of these symbols are used, and moreover this structure field looks like it is never written or read. unsigned char uuid[VIR_UUID_BUFLEN]; /* the domain unique identifier */ OK char *xml; /* the XML description for defined domains */ This field is, as far as I can tell, never set anywhere. However the code in hash.c does check whether it is set and will free it upon destruction of the _virDomain object. }; With this analysis in mind, attached is a patch which removes these three fields (path, flags, xml) and the unused virDomainFlags, with no apparent ill-effects. Rich. -- Emerging Technologies, Red Hat http://et.redhat.com/~rjones/ 64 Baker Street, London, W1U 7DF Mobile: +44 7866 314 421 Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Directors: Michael Cunningham (USA), Charlie Peters (USA) and David Owens (Ireland)