1. Create a blank memo

First, place a Trader Phone and right-click it with a parchment to obtain a phone number memo (Blank).

You have two ways to get a trader's phone number memo.

2-A. Directly use a blank memo on a trader

Go to the trader and right-click them with a blank memo.

You will obtain a written phone number memo immediately.

2-B. Phone number search

If you already know where the trader is, you can use the phone number search function in the Trader Phone.

1. Right-click any Trader Phone with a blank memo to open the phone number search GUI
2. Follow the instructions on the GUI; enter the trader's coordinates and click the 'Search' button
3. If the phone successfully finds the trader, their details will be shown on the GUI
4. Click the 'Write Down' button to obtain a written phone number memo

If 'Trader not found' was displayed in step 3, check the following and try again:

• Auto-detecting Y may fail, so you might need to enter it manually.
• If you took the coordinates from the map, zoom in and record them as accurately as possible.

3. Register the phone number memo to the Trader Phone and check the stock

Right-click the Trader Phone with the phone number memo obtained via 2-A or 2-B.

Once registered, you can right-click the Trader Phone anytime to check the assigned trader's stock.

Notes:

• Memos can be stored in scroll racks
• Use another written memo on the Trader Phone to reassign a different trader to it
• A written phone number memo can be used multiple times
  
  • You can give it to another player so they can register it to their Trader Phone
• Ctrl + Right-click opens the map, shows where the trader is and marks a waypoint
  • If any marker exists close enough, the new marker won't be created

A. No. This mod never keeps any chunk loaded nor trader entities on memory. Also my tests showed no unusual RAM usage.

The main potentially heavy process in this mod is loading chunk columns when searching traders or checking their stock.
First, the chunk loading never keep any chunk loaded nor keeps any trader entities on memory.
This is how I implemented it, and I verified it using `/stats` command and MemLeakInspector by elocrypt.

I also performed a test and it showed that the RAM usage is about the same as just walking/flying around the same area.
Moreover, in practice, searching/checking a trader loads only 4 chunk columns around them.
For comparison, when your view distance is 512, the game normally keeps about 450 chunk columns loaded around you.
So, using Trader Phone loads a few percent of what you'd load by visiting traders manually.

If you are curious about the test details, read on.

Test: Loading 4096 chunk columns

I performed a kind of volume test that forced the mod to load 4096 chunk columns through searching traders (note: it's equivalent to searching 1024 traders at once, which normally never happens).
This was performed in a standard survival world to reflect practical usage.
RAM usage comparison:
Before performing
  Client

 
  Server
 

* Client RAM usage is obtained from the debug window (Ctrl + F3). Server one is obtained from `/stats` command.

After performing
  Client

 
  Server

 
For those who are curious, here is the the RAM usage during performing:

  Client

  Server

You can see that more than 30,000 chunks were loaded, but they were unloaded after the process finished.

I also measured RAM usage of normal chunk loading, which occures during flying around the same area, without this mod installed:

Before performing

  Client

 
  Server

After performing
  Client

 
  Server

 
As you can see, both cases have almost the same amount of RAM usage.
(Both server RAM usage increased ~700MB)
Note that both consumes more RAM after performing, even after they unloaded unused chunks.
From my observation, the value does go down over time, but slowly.
It doesn’t seem to be only GC issue, since force GC didn’t have any immediate effect.

- Advanced Trader Phone
  - Multiple traders
- Stock GUI
  - Item slot (item visual)
  - Layout for better readability
    - Currently no concrete ideas
- Trader Phone model
  - Loving the current one's somewhat silly look, but it would be nice to have more cool/chic variants
    - Currently no concrete ideas
- Optimization
  - Stock result caching
- Make memos placeable in scrollrack and bookshelf
  - Though they're currently only scrollrakable but no idea how they sit nicely in bookshelves. I think only scrollrackable is enough at least for handy storage 
- More in-game guide
  - Handbook
  - Interaction tooltip
- Recolor or additional color for memos