Performance testing w BackupExec, comments requested.

[David Collier-Brown]

Jeremy wrote:
>>>The uname(2) system call conforms to SVr4, SVID, POSIX, and X/OPEN but is not
>>>available in BSD4.3.  If this call exists (configure test) and the "sysname"
>>>field is "Linux" and the "release" field, parsed from a string like
>>>2.6.8-2-686, shows the release to be greater than 2.6.15, then enable else
>>>disable.

Steve Langasek wrote:
>>Ugh. That's *horrible* :-). Tempting though.... :-).
>>No, this really is something vendors should address (IMHO).

   Sun tries (;-)) We like to make the linker do this checking,
actually. Interfaces have hidden numbers indicating what standard
they're from, like SISCD_2.3 and SYSVABI_1.3 or SUNW_1.1
If sendfile wasn't in the standard libs, you'd be linked
to a software emulation, thusly:

froggy> pvs -s /usr/lib/libsendfile.so | more
         libc.so.1 (SUNWprivate_1.1);
         libsendfile.so.1:
                 _edata;
                 _GLOBAL_OFFSET_TABLE_;
                 _end;
                 _etext;
                 _DYNAMIC;
                 _PROCEDURE_LINKAGE_TABLE_;
         SUNW_1.1:
                 sendfile;
                 sendfile64;
                 sendfilev64;
                 sendfilev;
        _LOCAL_:
                 _END_;
                 _fini;
                 _init;
                 _START_;
                 _sendfilev;
                 _sendfile64;
                 _sendfilev64;


   Macs sued to have something similar.
   If linux has this kind of low-level numbers in the ELF files,
we could just test for a new enough sendfile. Anyone know
Linux ELF well?

--dave


> 
> 
> Well, as Lawrence's vendor, the only way Debian would be addressing this
> would be by adding the uname check, so that we don't have to force the user
> to upgrade the kernel before installing a samba update...
> 

-- 
David Collier-Brown,      | Always do right. This will gratify
Sun Microsystems, Toronto | some people and astonish the rest
davecb at canada.sun.com     |                      -- Mark Twain
(416) 263-5733 (x65733)   |