there are 2 main ways of using the mod:
1. making a larger storage chest with the convenient access,
2. easy-to-use balancers, probably with the loaders.

In the first case, default setting are ok: the amount of slots in the merged chest equal to the sum of slots at all chests,
but in the second case, desired amount of slots is 1, we don't really need more slots for 7-to-5 balancer using the 1x5 chest, etc.

So may be add option to have new button in the action panel, that will create merging chests with only the 1 slot?

What is the performance difference between chest with 1000 slots set to only have one slot to insert into vs chest with just one slot? I guess there would be some but not that massive since only one slot is used by inserters in both cases

doesn't it still need to check all of them? at least the outputting ones

The mod allows you to limit amount of slots, so it should be easy to test in sandbox mode

140 1x21 chests,

update field a little bit lower for 1 slot limit in the settings,
screenshots: https://drive.google.com/open?id=1wzbtRbJiMbNJFxs1VI28gBXmLIPiT5m1&usp=drive_fs

Update field:
1000 slots: 42.4
1000 slots: 30

1 slot soft limit: 11.2
1 slot soft limit: 10.8

1 slot settings: 7.3
1 slot settings: 8.3

loaders, no chests: 1.1

That's some good testing, thank you for that. Interesting, I wouldn't think it would be this much of a difference.

Do you think it would be worth the effort to implement this? I guess it would require new merge tool, copy of all merged prototypes (which already is quite a lot) and modification of merge/split code.

I don't know how internally it is made, so I can't evaluate complexity,
and for the problem of amount of prototypes you could make default max area 2 times lower.

Also if the amount of prototypes is the problem, full rebalance of default settings could be made: something like 55x55x225:
squares up to 15x15, and lines up to 8 wagons (6*8+7=55)

exist as separate mod now
https://mods.factorio.com/mod/BigContainersUPSPlus

I totally forgot it existed as https://mods.factorio.com/mod/verysmallchests as well, which has support in merging chests

for anyone reading this thread, since 5.1.0, together with the Merging Chests Override Size Settings
it is possible to to set up steel chests to be #1 and iron chests to be #2, with just 1 slot.

for anyone reading this thread, since 5.1.0, together with the Merging Chests Override Size Settings
it is possible to to set up steel chests to be #1 and iron chests to be #2, with just 1 slot.

How exactly do you do this? That addon lets you configure the dimensions, area, and whitelist, but not inventory max size.

it may be the second new one, the Merging Chests Override Inventory Settings

It was, ty.

I read the topic and thought that the problem with the number of slots can be solved by transfering the required number slots in the white list of chests to be combined - 10x5x2 12x7x20 (width * height * number of slots). I think this will not require much modification of the mod.