Re: Playing with namespaces and bloat-o-meeter

[Cedric Le Goater <clg-NmTC/0ZBporQT0dZR+AlfA@public.gmane.org>]

Serge E. Hallyn wrote:
> Quoting Pavel Emelyanov (xemul-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org):
>> Hi, guys!
>>
>> I've noticed that compiling out all the core related to
>> cloning and cleaning the new namespace saves us more than
>> a Kbyte (!) from the vmlinux.
>>
>> add/remove: 19/0 grow/shrink: 6/6 up/down: 1532/-336 (1196)
>> function                                     old     new   delta
>> copy_user_ns                                   -     181    +181
>> copy_ipcs                                      -     149    +149
>> copy_utsname                                   -     120    +120
>> shm_exit_ns                                    -     106    +106
>> sem_exit_ns                                    -     106    +106
>> msg_exit_ns                                    -     106    +106
>> freeary                                        -     100    +100
>> release_uids                                   -      95     +95
>> freeque                                        -      92     +92
>> free_nsproxy                                  48      99     +51
>> __sem_init_ns                                  -      45     +45
>> shm_init_ns                                    -      42     +42
>> sem_init_ns                                    -      42     +42
>> msg_init_ns                                    -      42     +42
>> __shm_init_ns                                  -      38     +38
>> create_new_namespaces                        300     335     +35
>> __msg_init_ns                                  -      31     +31
>> sysvipc_proc_release                           5      35     +30
>> free_ipc_ns                                    -      30     +30
>> do_shm_rmid                                    -      29     +29
>> shm_release                                   18      39     +21
>> free_user_ns                                   -      16     +16
>> sysvipc_proc_open                            100     111     +11
>> do_shmat                                     778     787      +9
>> free_uts_ns                                    -       5      +5
>> sys_shmctl                                  1934    1907     -27
>> msg_init                                      82      47     -35
>> shm_init                                      92      47     -45
>> sem_init                                      99      44     -55
>> sys_msgctl                                  1394    1311     -83
>> sys_semctl                                  2123    2032     -91
>>
>> Since there already were some questions like "do I need it
>> on my cellphone?" in reply to pid namespaces patches and 
>> so on, why don't we make ALL the namespaces cloning code 
>> under the config option to make those people happy?
>>
>> Here's the proposed patch.
> 
> How about a single config variable for all namespaces?

yes good idea.

C.