The idx v4 type table supersedes the global type queue: workers no longer
enqueue every Write(Type) into a shared ConcurrentQueue during the freeze,
WriteFiles no longer drains and dedupes millions of entries, and the db file
is no longer produced. Loading old saves still reads SerializedTypes.db via
the legacy v2/v3 path.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
### Summary
- `GenericEntityPersistence` is now a type of `GenericPersistence`. This allows developers to serialize both entities and non-entities in the same system. 🎉
- Each `SerializationThreadWorker` now allocates 1MB of heap for serialization _permanently_. If more memory is needed, that thread will double it's memory, not to exceed increments of 64MB.
- Several bugs with serialization introduced with the pure MMF implementation have been fixed.
- `BinaryFileReader` has been added back. 🎉
- Adds `world.useMultithreadedSaves` to allow disabling threaded saves.
> [!IMPORTANT]
> **Developer Note**
> The split file serialization has been deprecated and is no longer used. We have effectively gone back to the same file writing we had before the pure MMF implementation.
### Summary
Updates the serialization strategy to use `MemoryMappedFile` instead of thick buffers. This has the benefit of being on-par with the current implementation (based on hardware/OS), however won't incur the double-memory issue.
> [!Important]
> **Developer Note**
> The `BinaryFileWriter` and `BinaryFileReader` has been removed in favor of `MemoryMapFileWriter` and `UnmanagedDataReader`
### Summary
- [X] Fixed a bug where entity persistence was serialized out of order, causing world corruption.
- [X] Fixed LastSerialized not being utilized properly and dangling references still becoming an issue.
- [X] Added a new `GenericEntityPersistence<T>` type to encapsulate `ISerializable` serialization.
- [X] Removing the custom logic and moved Items, Mobiles, Guilds, and Accounts to GenericEntityPersistence.
- [X] Changed serialization to use the singleton pattern to reduce calling methods from stored variables.
## Changes
* Improves type hashing by introducing xxHash3 (64bit)
* Removes individual `tdb` files in favor of a single `SerializedTypes.db` file. This file is only used to identify a type that is being deserialized, which doesn't exist.
* Adds duplicate type alias detection
* Adds `AssemblyHandler.FindTypeByHash`
View changed files whitespaces: https://github.com/modernuo/ModernUO/pull/1172/files?diff=split&w=1
## SerializedTypes.db
The serialized types file is used to get back the original name of a type in case it no longer exists in code. This can easily be necessary if a class is renamed in code and no `TypeAlias` is provided.
### Format
byte[4] - version
byte[4] - count
--array--
byte[8] - xxHash
byte[1] - flag, 0 - null, 1 - not null
byte[n] - Full class name in UTF8
### Example
<img width="472" alt="SerializedTypes_Example" src="https://user-images.githubusercontent.com/3953314/195255429-31d24293-6bd1-419e-811b-07874dd0f78d.png">
## Benchmarks
Serialized 500 Type fields. The 8192bytes comes from the _ConcurrentQueue_ that would later be used for SerializedTypes.
Note that the queue is never cleared, so it's size grew considerably.
```cs
| Method | Mean | Error | StdDev | Allocated |
|--------------------- |---------:|---------:|---------:|----------:|
| BenchmarkXXHash | 18.44 us | 0.278 us | 0.260 us | 8192 B |
| BenchmarkTypeStrings | 25.09 us | 0.292 us | 0.259 us | - |
```
TODO:
* Add support in the Serialization Generator for `ReadType()` and `Write(Type)`
* Remove `SetTypeRef` from Serialization Generator
**Only one functional change**
* Fixes a bug in LogFactory where `Warning` is being logged as `Information`
Non-functional changes:
* Updates/Fixes copyright headers
* Removes namespace scopes for core files.
View with [whitespace off](https://github.com/modernuo/ModernUO/pull/1187/files?w=1).
- [X] Adds `AdhocPersistence` which replaces RunUO `Persistence`
- [X] Fixes a few minor bugs with EntityPersistence deserialization
- [X] Reverts/updates some serialization changes
