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21 commits

Author SHA1 Message Date
8e7e680afe
First adaptation to WIP netapp with streaming body 2022-07-29 12:25:02 +02:00
b44d3fc796 Abstract database behind generic interface and implement alternative drivers (#322)
- [x] Design interface
- [x] Implement Sled backend
  - [x] Re-implement the SledCountedTree hack ~~on Sled backend~~ on all backends (i.e. over the abstraction)
- [x] Convert Garage code to use generic interface
- [x] Proof-read converted Garage code
- [ ] Test everything well
- [x] Implement sqlite backend
- [x] Implement LMDB backend
- [ ] (Implement Persy backend?)
- [ ] (Implement other backends? (like RocksDB, ...))
- [x] Implement backend choice in config file and garage server module
- [x] Add CLI for converting between DB formats
- Exploit the new interface to put more things in transactions
  - [x] `.updated()` trigger on Garage tables

Fix #284

**Bugs**

- [x] When exporting sqlite, trees iterate empty??
- [x] LMDB doesn't work

**Known issues for various back-ends**

- Sled:
  - Eats all my RAM and also all my disk space
  - `.len()` has to traverse the whole table
  - Is actually quite slow on some operations
  - And is actually pretty bad code...
- Sqlite:
  - Requires a lock to be taken on all operations. The lock is also taken when iterating on a table with `.iter()`, and the lock isn't released until the iterator is dropped. This means that we must be VERY carefull to not do anything else inside a `.iter()` loop or else we will have a deadlock! Most such cases have been eliminated from the Garage codebase, but there might still be some that remain. If your Garage-over-Sqlite seems to hang/freeze, this is the reason.
  - (adapter uses a bunch of unsafe code)
- Heed (LMDB):
  - Not suited for 32-bit machines as it has to map the whole DB in memory.
  - (adpater uses a tiny bit of unsafe code)

**My recommendation:** avoid 32-bit machines and use LMDB as much as possible.

**Converting databases** is actually quite easy. For example from Sled to LMDB:

```bash
cd src/db
cargo run --features cli --bin convert -- -i path/to/garage/meta/db -a sled -o path/to/garage/meta/db.lmdb -b lmdb
```

Then, just add this to your `config.toml`:

```toml
db_engine = "lmdb"
```

Co-authored-by: Alex Auvolat <alex@adnab.me>
Reviewed-on: Deuxfleurs/garage#322
Co-authored-by: Alex <alex@adnab.me>
Co-committed-by: Alex <alex@adnab.me>
2022-06-08 10:01:44 +02:00
5768bf3622 First implementation of K2V (#293)
**Specification:**

View spec at [this URL](https://git.deuxfleurs.fr/Deuxfleurs/garage/src/branch/k2v/doc/drafts/k2v-spec.md)

- [x] Specify the structure of K2V triples
- [x] Specify the DVVS format used for causality detection
- [x] Specify the K2V index (just a counter of number of values per partition key)
- [x] Specify single-item endpoints: ReadItem, InsertItem, DeleteItem
- [x] Specify index endpoint: ReadIndex
- [x] Specify multi-item endpoints: InsertBatch, ReadBatch, DeleteBatch
- [x] Move to JSON objects instead of tuples
- [x] Specify endpoints for polling for updates on single values (PollItem)

**Implementation:**

- [x] Table for K2V items, causal contexts
- [x] Indexing mechanism and table for K2V index
- [x] Make API handlers a bit more generic
- [x] K2V API endpoint
- [x] K2V API router
- [x] ReadItem
- [x] InsertItem
- [x] DeleteItem
- [x] PollItem
- [x] ReadIndex
- [x] InsertBatch
- [x] ReadBatch
- [x] DeleteBatch

**Testing:**

- [x] Just a simple Python script that does some requests to check visually that things are going right (does not contain parsing of results or assertions on returned values)
- [x] Actual tests:
  - [x] Adapt testing framework
  - [x] Simple test with InsertItem + ReadItem
  - [x] Test with several Insert/Read/DeleteItem + ReadIndex
  - [x] Test all combinations of return formats for ReadItem
  - [x] Test with ReadBatch, InsertBatch, DeleteBatch
  - [x] Test with PollItem
  - [x] Test error codes
- [ ] Fix most broken stuff
  - [x] test PollItem broken randomly
  - [x] when invalid causality tokens are given, errors should be 4xx not 5xx

**Improvements:**

- [x] Descending range queries
  - [x] Specify
  - [x] Implement
  - [x] Add test
- [x] Batch updates to index counter
- [x] Put K2V behind `k2v` feature flag

Co-authored-by: Alex Auvolat <alex@adnab.me>
Reviewed-on: Deuxfleurs/garage#293
Co-authored-by: Alex <alex@adnab.me>
Co-committed-by: Alex <alex@adnab.me>
2022-05-10 13:16:57 +02:00
d8ab5bdc3e
New buckets for 0.6.0: fix model and migration 2022-01-04 12:47:28 +01:00
5b1117e582
New model for buckets 2022-01-04 12:45:46 +01:00
8f6026de5e
Make table name a const in trait 2021-12-15 15:39:10 +01:00
e4b9e4e24d
rename types to CamelCase 2021-05-03 22:15:09 +02:00
f5a0cf0414
fix clippy warnings on table 2021-05-03 22:11:41 +02:00
2812a027ea
change some more comments and revert changes on TableSchema 2021-04-27 16:49:07 +02:00
74373aebcf
make most requested changes 2021-04-27 16:47:08 +02:00
b437610812
attempt at documenting table crate 2021-04-27 16:37:10 +02:00
831eb35763 cargo fmt 2021-03-12 21:52:19 +01:00
c475471e7a Implement table gc, currently for block_ref and version only 2021-03-12 19:57:37 +01:00
2afd2c81ba Change hash function to blake2 for partition keys based on strings 2021-03-10 16:23:57 +01:00
f319a7d374 Refactor model stuff, including cleaner CRDTs 2021-03-10 16:21:56 +01:00
bf25c95fe2 Make updated() be a sync function that doesn't fail 2021-02-23 20:25:15 +01:00
b1b640ae8b rename hash() to sha256sum(), we might want to change it at some places 2021-02-21 15:24:30 +01:00
f8a04852a2 Convert bucket table to better CRDT representation 2020-11-20 23:53:54 +01:00
e9fd265ce6 Slight refactoring to make things clearer with DeletedFilter 2020-11-20 20:11:04 +01:00
44dba0e53c cargo fmt 2020-07-08 17:34:37 +02:00
86bf4dedac Add support for model migrations 2020-07-08 16:10:53 +02:00