Re: [Libvir] libvirt statistics

[Using `pahole' and friends - see http://git.kernel.org/?p=linux/kernel/git/acme/pahole.git;a=summary and https://ols2006.108.redhat.com/2007/Reprints/melo-Reprint.pdf ] These are all on x86-64. You'll get slightly different results on a 32 bit arch. Largest structures, by size: qemud_vm_def: 16608 4 qemud_vm_os_def: 16436 1 _testConn: 14504 2

Structures with holes which could be made smaller by packaging (third number is how many bytes you'd save per allocation):

_xmlValidCtxt 112 104 8 _xmlEntity 136 128 8 _xmlParserCtxt 696 672 24 _testConn 14504 14496 8 _xmlURI 80 72 8 _xmlXPathObject 72 56 16 _xmlXPathParserContext 80 72 8 _xmlXPathContext 352 336 16 _xmlError 88 80 8 _xmlAttr 96 88 8 _xmlDoc 168 160 8 _xmlNode 120 112 8

Functions with the most parameters (in C these are dangerous because of C's lousy typechecking): __virRaiseError: 12

All global variables (nothing wrong with global variables, I say): extern unsigned int __invalid_size_argument_for_IOC; /* 0 */

struct qemu_feature_flags arch_info_i686_flags[4]; /* 0 */ struct qemu_feature_flags arch_info_x86_64_flags[3]; /* 0 */ struct qemud_driver * qemu_driver; /* 0 */ struct qemu_arch_info qemudArchs[7]; /* 1 */

extern struct _IO_FILE * stderr; /* 9 */ extern struct _IO_FILE * stdin; /* 23 */ extern struct _IO_FILE * stdout; /* 23 */

enum /**/ virDrvOpenRemoteFlags; /* 0 */

struct xenUnifiedDriver xenDaemonDriver; /* 1 */ struct xenUnifiedDriver xenHypervisorDriver; /* 1 */ struct xenUnifiedDriver xenProxyDriver; /* 1 */ struct xenUnifiedDriver xenStoreDriver; /* 1 */ struct xenUnifiedDriver xenXMDriver; /* 1 */

extern xmlFreeFunc xmlFree; /* 3 */ extern xmlMallocFunc xmlMalloc; /* 0 */