so most most D&D 5e players that have played for a bit know of goodberry, and how it can completely ruin the foraging component of a survival campaigns, so i thought how powerful is good berry for 'feeding the masses'

so first who can cast goodberry: rangers & druids, well as you will see later that whilst druid only gets 7 more spell slots(at 20th level) there is a variant rule that turns this into many, many more

so we go with druid giving a base 22 castings of goodberry or enough to feed 220 people, pair that with a decanter of endless water & those 220 people will survive for a very long time(until the die of other causes or you die), but it gets worse

if we give the player a boon of high magic that gives us another 9th level spell slot, so ten more people

and we give them 3 pearls of powers, another 30 people

At this point we are providing food and water for 260 people, but with the afore mentioned variant rule this increases by a huge factor

this rule is spell points: at 20th level we have 133 spell points of which we can cast goodberry at 1st level for 2...

then we give the player 13 extra spell points for their boon of high magic...

and restore 5 points with each pearl of power for a total of 15 points...

giving us 161 spell points, which allows us to cast goodberry 80 times, feeding up to 800 people...

which allow us to accelerate a spear to 667.5 Ft/second

if anyone could let me know of a better way to spend my attunement slots then i would be happy to edit this post 

For accelerating a spear - nope. The raw doesn't support momentum even if your DM was stupid enough to allow hundreds of people in a single combat and enforcing 1 round = 6 seconds (which is a guide, not a rule). 

As for feeding people: seems like a huge amount of wasted spell slots and attunement slots to replicate a Cauldron of Plenty or two.

I appreciate your passion for the details and math of such a thing, however.

Given the following question from players:

"Do I have enough food or can I come up with (conjure, hunt, buy, steal, trade, etc.) enough food to 'feed the masses'?

I would (as a DM) rule in the following way:

Say yes, and hand wave it. No further detail or explanation necessary. You save the day. Win the crowd. Appease the masses. Gain reputation/favor, etc. The masses are fed and you are applauded for it and showered with love and loot.

Say no, and hand wave it. It's just not feasible and would take more time, energy, and resources than our game-time would allow for you to detail such a thing. Therefore, choose X amount of people to feed. Everyone else - given the situation/environment, will in fact - starve.