Cacti vs MRTG w/rrdtool?

[PaulH316]

-A system polls dozens of devices with ~4000 interfaces
-Current MRTG system requires multiple threads to complete polling withing 5 minutes.
-Polling system performance is significantly reduced during MRTG execution.
-Polled systems frequently change hardware (modules added/removed) so periodic config/parameter updates are needed across the board. This currently is easily handled with a single script to updated all configs periodically.
Question:
Would Cacti offer a better alternative than moving MRTG to rrdtool logging?
IE - would the performance increase from moving away from MRTG png generation be traded for a performance loss as data for 4K interfaces is loaded into mysql.
Also, is there a simple script process to update all devices periodically?
Thanks

[gandalf]

Using spine as a poller, the Cacti ecosystem is indeed very fast. But it does not create graphs unless you request that; it will only update rrd files unless the web UI is used for graphing.
Since late, cacti supports cli scripts to automate tasks. Users reported that they achieved results like yours by wrapping some code around our cli scripts (add_host, add_graph, add_tree, ...), generating exactly those graphs/rrd files that are required (e.g. traffic graphs for all interfaces that are "up")
BTB: there is currently no know script to migrate from MRTG config files ...
Reinhard