jepsen: refactoring

This commit is contained in:
Alex 2023-10-19 14:34:19 +02:00
parent b3bf16ee27
commit 74e50edddd
5 changed files with 70 additions and 30 deletions

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@ -31,6 +31,39 @@ lein run test --nodes-file nodes.vagrant --time-limit 64 --rate 50 --concurrenc
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

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@ -56,12 +56,12 @@
(gen/stagger (/ (:rate opts)))
(gen/nemesis
(cycle [(gen/sleep 5)
;{:type :info, :f :partition-start}
;(gen/sleep 5)
{:type :info, :f :partition-start}
(gen/sleep 5)
{:type :info, :f :clock-scramble}
(gen/sleep 5)
;{:type :info, :f :partition-stop}
;(gen/sleep 5)
{:type :info, :f :partition-stop}
(gen/sleep 5)
{:type :info, :f :clock-scramble}]))
(gen/time-limit (:time-limit opts)))
(gen/log "Healing cluster")

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@ -43,7 +43,7 @@
"rpc_bind_addr = \"0.0.0.0:3901\"\n"
"rpc_public_addr = \"" node ":3901\"\n"
"db_engine = \"lmdb\"\n"
"replication_mode = \"3\"\n"
"replication_mode = \"2\"\n"
"data_dir = \"" data-dir "\"\n"
"metadata_dir = \"" meta-dir "\"\n"
"[s3_api]\n"

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@ -9,6 +9,7 @@
[generator :as gen]
[independent :as independent]
[nemesis :as nemesis]
[util :as util]
[tests :as tests]]
[jepsen.checker.timeline :as timeline]
[jepsen.control.util :as cu]
@ -25,33 +26,31 @@
(defrecord RegClient [creds]
client/Client
(open! [this test node]
(let [creds (grg/creds node)]
(info node "s3 credentials:" creds)
(assoc this :creds creds)))
(assoc this :creds (grg/creds node)))
(setup! [this test])
(invoke! [this test op]
(let [[k v] (:value op)]
(case (:f op)
:read
(try+
(util/timeout
10000
(assoc op :type :fail, :error ::timeout)
(let [value (s3/get (:creds this) k)]
(assoc op :type :ok, :value (independent/tuple k value)))
(catch (re-find #"Unavailable" (.getMessage %)) ex
(assoc op :type :fail, :error [:s3-error (.getMessage ex)])))
(assoc op :type :ok, :value (independent/tuple k value))))
:write
(try+
(util/timeout
10000
(assoc op :type :info, :error ::timeout)
(do
(s3/put (:creds this) k v)
(assoc op :type :ok))
(catch (re-find #"Unavailable" (.getMessage %)) ex
(assoc op :type :fail, :error [:s3-error (.getMessage ex)]))))))
(assoc op :type :ok))))))
(teardown! [this test])
(close! [this test]))
(defn workload
"Tests linearizable reads and writes"
[opts]
{:client (client/timeout 10 (RegClient. nil))
{:client (RegClient. nil)
:checker (independent/checker
(checker/compose
{:linear (checker/linearizable
@ -59,8 +58,8 @@
:algorithm :linear})
:timeline (timeline/html)}))
:generator (independent/concurrent-generator
(/ (:concurrency opts) 10) ; divide threads in 10 groups
(range) ; working on 10 keys
10
(range)
(fn [k]
(->>
(gen/mix [op-get op-put op-del])

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@ -11,6 +11,7 @@
[generator :as gen]
[independent :as independent]
[nemesis :as nemesis]
[util :as util]
[tests :as tests]]
[jepsen.checker.timeline :as timeline]
[jepsen.control.util :as cu]
@ -26,23 +27,29 @@
(defrecord SetClient [creds]
client/Client
(open! [this test node]
(let [creds (grg/creds node)]
(info node "s3 credentials:" creds)
(assoc this :creds creds)))
(assoc this :creds (grg/creds node)))
(setup! [this test])
(invoke! [this test op]
(let [[k v] (:value op)
prefix (str "set" k "/")]
(case (:f op)
:add
(do
(s3/put (:creds this) (str prefix v) "present")
(assoc op :type :ok))
(util/timeout
10000
(assoc op :type :info, :error ::timeout)
(do
(s3/put (:creds this) (str prefix v) "present")
(assoc op :type :ok)))
:read
(let [items (s3/list (:creds this) prefix)
items-stripped (map (fn [o] (str/replace-first o prefix "")) items)
items-set (set (map read-string items-stripped))]
(assoc op :type :ok, :value (independent/tuple k items-set))))))
(util/timeout
10000
(assoc op :type :fail, :error ::timeout)
(let [items (s3/list (:creds this) prefix)
items-stripped (map (fn [o]
(assert (str/starts-with? o prefix))
(str/replace-first o prefix "")) items)
items-set (set (map parse-long items-stripped))]
(assoc op :type :ok, :value (independent/tuple k items-set)))))))
(teardown! [this test])
(close! [this test]))
@ -110,6 +117,7 @@
10
(range)
(fn [k]
(gen/mix [op-add-rand100 op-read])))})
(->> (gen/mix [op-add-rand100 op-read])
(gen/limit (:ops-per-key opts)))))})