[CentOS] is yum a complete substitute of rpm?

Tue Feb 16 15:04:30 UTC 2010
R P Herrold <herrold at centos.org>

On Mon, 15 Feb 2010, Bowie Bailey wrote:

> I use rpm for basic stuff because it runs faster.  For example:
>
> $ time yum list installed
> ...
> real    0m17.069s
> user    0m0.857s
> sys     0m0.675s
>
> $ time rpm -qa
> ...
> real    0m4.714s
> user    0m4.457s
> sys     0m0.120s
>
> Yum tends to take a while to read in its databases before it processes
> your command.  So for simple commands, it is faster to use rpm.  On slow
> boxes, it can be significantly faster.

naw -- The 'speed' issue here comes down to a scripting 
language v a compiled one -- librpm underneath on each in 
CentOS 5.  Here is a more apple to apples comparison on those 
timings on the work being done

[herrold at centos-5 clang]$ time rpm -qa --nosignature \
 	--nodigest > /dev/null

real    0m0.329s
user    0m0.208s
sys     0m0.076s
[herrold at centos-5 clang]$ time yum list installed > /dev/null

real    0m4.252s
user    0m1.948s
sys     0m0.132s
[herrold at centos-5 clang]$

-- Russ herrold