[Yum] A couple of problems and RFE for Yum

[seth vidal]

> That COULD be atomic, but it may or may not be worth it.  If I
> understand correctly, you currently do this:
> 
> 1) write to .newheaders
> 2) rename headers to .oldheaders
> 3) rename .newheaders to headers
> 
> If you instead do
> 
> 1) write to .newheaders
> 2) COPY headers to .oldheaders
> 3) rename .newheaders to headers

the copy operation could take forever and a day is my concern.
and in that time, depending on what changed on the repo, the headers are
out of date to the rpms.


> Then it should be atomic.  That's a significantly heavier operation,
> though.

and you'd have to remove headers at some point. 

> Another alternative is:
> 
> 1) write to .newheaders
> 2) HARD LINK headers to .oldheaders
> 3) rename .newheaders to headers
> 
> That's efficient, but requires hard links :)

which not all filesystems have, right.


-sv