yesterday I took some training at MT RouterOS topics. Part of the training was queuing. Currently we use Simple queues, on per user base. It was initial quick hack on our part, to get it running "some way". But lector suggested to swithc to queue trees, stating some things, I am not all that sure about:
1) Simple queues sometimes do not work correctly - e.g. when you have parent max-limit set to e.g. 500, and childs consume e.g. 600 in total, it is correct child settings will override parent one, but parent still shows incorrectly 500, instead of total of childs ... is that correct?
2) Simple queues "slow down" router, because they do aply at the end of the packet flow diagram (interface queue before output-interface), but my materials from MUM state, that Simple queues are executed on global-out and global-in. So?
It all was mentioned in regards to NAT. Currently we have each node natted, from historical reasons, but switching to routed network. However, due to NAT (masquarade) on central router, we were suggested to put one other router in front of it, doing masquarading only, and let our main router being purely routed, that simply queues work better then.
Looking at packet flow diagram, I am somehow confused, why in the case of either simple queue or queue trees using mangle, there should be a problem with correct packet marking and later using in queue (queue trees), or problems with using simple queues ...
Could someone please clear the situation to me? What phase of packet flow diagram does both simple queues, and queue trees do take part at?
Thank you very much,