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feat: bump to Rust edition 2024 (#132)

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* feat: bump to Rust edition 2024

Signed-off-by: Alex Chi <iskyzh@gmail.com>

* allow deadcode

Signed-off-by: Alex Chi <iskyzh@gmail.com>

* fix deploy to pages

Signed-off-by: Alex Chi <iskyzh@gmail.com>

* fix fmt

Signed-off-by: Alex Chi <iskyzh@gmail.com>

* update actions

Signed-off-by: Alex Chi <iskyzh@gmail.com>

---------

Signed-off-by: Alex Chi <iskyzh@gmail.com>
This commit is contained in:
Alex Chi Z.
2025-03-09 16:11:52 -04:00
committed by GitHub
parent 662b1a855f
commit 1d9693c22f
38 changed files with 76 additions and 73 deletions
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mini-lsm-book/src/week1-01-memtable.md
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@@ -33,7 +33,7 @@ crossbeam-skiplist provides similar interfaces to the Rust std's `BTreeMap`: ins
You will also notice that the `MemTable` structure does not have a `delete` interface. In the mini-lsm implementation, deletion is represented as a key corresponding to an empty value.
In this task, you will need to implement `MemTable::get` and `MemTable::put` to enable modifications of the memtable.
In this task, you will need to implement `MemTable::get` and `MemTable::put` to enable modifications of the memtable. Note that `put` should always overwrite a key if it already exists. You won't have mutiple entries of the same key in a single memtable.
We use the `bytes` crate for storing the data in the memtable. `bytes::Byte` is similar to `Arc<[u8]>`. When you clone the `Bytes`, or get a slice of `Bytes`, the underlying data will not be copied, and therefore cloning it is cheap. Instead, it simply creates a new reference to the storage area and the storage area will be freed when there are no reference to that area.
@@ -157,6 +157,7 @@ Now that you have multiple memtables, you may modify your read path `get` functi
## Test Your Understanding
* Why doesn't the memtable provide a `delete` API?
* Does it make sense for the memtable to store all write operations instead of only the latest version of a key? For example, the user puts a->1, a->2, and a->3 into the same memtable.
* Is it possible to use other data structures as the memtable in LSM? What are the pros/cons of using the skiplist?
* Why do we need a combination of `state` and `state_lock`? Can we only use `state.read()` and `state.write()`?
* Why does the order to store and to probe the memtables matter? If a key appears in multiple memtables, which version should you return to the user?