 |
 |
Archives of the TeradataForum
Message Posted: Fri, 02 Feb 2007 @ 12:41:01 GMT
| Subj: | | Re: How Do You Measure/Validate Compression Savings? |
| |
| From: | | Victor Sokovin |
| | - Re "saving nodes": Saving nodes cannot be calculated only on space. Both space and compute/IO resources must be considered. MVC's space
savings is not in the same proportion as the resource savings. Thus, purely for example your mileage will vary, if you save 30% of space you may
well only save 5% of CPU/IO for a particular workload. Thus the number of nodes saved would only be 5% if holding response time/throughput
constant was the goal. | |
I was not following this thread so only catching up.
I think MVC might actually lead to the *increase* in, say, CPU usage if MVC is liberally applied to "small" tables on a large scale. If there
is compressing then there must be uncompressing going on somewhere down the line, no? It is hard to measure all the effects without access to a
good test lab, though.
The idea of having a tool for MVC never occurred to me before I read the thread, probably because of the fear of compressing "small" tables and
causing weird adverse effects elsewhere.
Regards,
Victor
| |
