path: root/script/jepsen.garage/README.md

# jepsen.garage

Jepsen checking of Garage consistency properties.

## Usage

Requirements:

- vagrant
- VirtualBox, configured so that nodes can take an IP in a private network `192.168.56.0/24`
- a user that can create VirtualBox VMs
- leiningen
- gnuplot

Set up VMs:

```
vagrant up
```

Run tests (this one should fail):

```
lein run test --nodes-file nodes.vagrant --time-limit 64 --concurrency 50 --rate 50 --workload reg
```

These ones are working:

```
lein run test --nodes-file nodes.vagrant --time-limit 64 --rate 50  --concurrency 50 --workload set1
lein run test --nodes-file nodes.vagrant --time-limit 64 --rate 50  --concurrency 50 --workload set2
```

## Results

**Register linear, without timestamp patch**

Command: `lein run test --nodes-file nodes.vagrant --time-limit 60 --rate 20  --concurrency 20 --workload reg --ops-per-key 100`

Results: fails with a simple clock-scramble nemesis.

Explanation: without the timestamp patch, nodes will create objects using their
local clock only as a timestamp, so the ordering will be all over the place if
clocks are scrambled.

**Register linear, with timestamp patch**

Command: `lein run test --nodes-file nodes.vagrant --time-limit 60 --rate 20  --concurrency 20 --workload reg --ops-per-key 100 -I`

Results:

- No failure with clock-scramble nemesis
- Fails with clock-scramble nemesis + partition nemesis

Explanation: S3 objects are not meant to behave like linearizable registers. TODO explain using a counter-example

**Read-after-write CRDT register model**: TODO: determine the expected semantics of such a register, code a checker and show that results are correct

**Set, basic test**

Command: `lein run test --nodes-file nodes.vagrant --time-limit 60 --rate 20  --concurrency 20 --workload set1 --ops-per-key 100`

Results:

- ListObjects returns objects not within prefix????

## License

Copyright © 2023 Alex Auvolat

This program and the accompanying materials are made available under the
terms of the GNU Affero General Public License v3.0.