Merge pull request 'Jepsen testing (NLnet task 3 subtask 1)' (#544) from jepsen into main

Reviewed-on: https://git.deuxfleurs.fr/Deuxfleurs/garage/pulls/544

5 files changed, 620 insertions, 0 deletions

diff --git a/script/jepsen.garage/src/jepsen/garage/daemon.clj b/script/jepsen.garage/src/jepsen/garage/daemon.clj
new file mode 100644
index 00000000..d407dd29
--- /dev/null
+++ b/script/jepsen.garage/src/jepsen/garage/daemon.clj
@@ -0,0 +1,152 @@
+(ns jepsen.garage.daemon
+  (:require [clojure.tools.logging :refer :all]
+            [jepsen [control :as c]
+             [core :as jepsen]
+             [db :as db]]
+            [jepsen.control.util :as cu]))
+
+; CONSTANTS -- HOW GARAGE IS SET UP
+
+(def base-dir "/opt/garage")
+(def data-dir (str base-dir "/data"))
+(def meta-dir (str base-dir "/meta"))
+(def binary (str base-dir "/garage"))
+(def logfile (str base-dir "/garage.log"))
+(def pidfile (str base-dir "/garage.pid"))
+
+(def admin-token "icanhazadmin")
+(def access-key-id "GK8bfb6a51286071c6c9cd8bc3")
+(def secret-access-key "b0be95f71c1c6f16858a9edf395078b75c12ecb6b1c03385c4ae92076e4994a3")
+(def bucket-name "jepsen")
+
+; THE GARAGE DB
+
+(defn install!
+  "Download and install Garage"
+  [node version]
+  (c/su
+    (c/trace
+      (info node "installing garage" version)
+      (c/exec :mkdir :-p base-dir)
+      (let [url (str "https://garagehq.deuxfleurs.fr/_releases/" version "/x86_64-unknown-linux-musl/garage")
+            cache (cu/cached-wget! url)]
+        (c/exec :cp cache binary))
+      (c/exec :chmod :+x binary))))
+
+(defn configure!
+  "Configure Garage"
+  [node]
+  (c/su
+    (c/trace
+      (cu/write-file!
+        (str "rpc_secret = \"0fffabe52542c2b89a56b2efb7dfd477e9dafb285c9025cbdf1de7ca21a6b372\"\n"
+             "rpc_bind_addr = \"0.0.0.0:3901\"\n"
+             "rpc_public_addr = \"" node ":3901\"\n"
+             "db_engine = \"lmdb\"\n"
+             "replication_mode = \"2\"\n"
+             "data_dir = \"" data-dir "\"\n"
+             "metadata_dir = \"" meta-dir "\"\n"
+             "[s3_api]\n"
+             "s3_region = \"us-east-1\"\n"
+             "api_bind_addr = \"0.0.0.0:3900\"\n"
+             "[k2v_api]\n"
+             "api_bind_addr = \"0.0.0.0:3902\"\n"
+             "[admin]\n"
+             "api_bind_addr = \"0.0.0.0:3903\"\n"
+             "admin_token = \"" admin-token "\"\n"
+             "trace_sink = \"http://192.168.56.1:4317\"\n")
+        "/etc/garage.toml"))))
+
+(defn connect-node!
+  "Connect a Garage node to the rest of the cluster"
+  [test node]
+  (c/trace
+    (let [node-id (c/exec binary :node :id :-q)]
+      (info node "node id:" node-id)
+      (c/on-many (:nodes test)
+                 (c/exec binary :node :connect node-id)))))
+
+(defn configure-node!
+  "Configure a Garage node to be part of a cluster layout"
+  [test node]
+  (c/trace
+    (let [node-id (c/exec binary :node :id :-q)]
+      (c/on (jepsen/primary test)
+          (c/exec binary :layout :assign (subs node-id 0 16) :-c :1G :-z :dc1 :-t node)))))
+
+(defn finalize-config!
+  "Apply the layout and create a key/bucket pair in the cluster"
+  [node]
+  (c/trace
+    (c/exec binary :layout :apply :--version 1)
+    (info node "garage status:" (c/exec binary :status))
+    (c/exec binary :key :import access-key-id secret-access-key :--yes)
+    (c/exec binary :bucket :create bucket-name)
+    (c/exec binary :bucket :allow :--read :--write bucket-name :--key access-key-id)
+    (info node "key info: " (c/exec binary :key :info access-key-id))))
+
+(defn db
+  "Garage DB for a particular version"
+  [version]
+  (reify db/DB
+    (setup! [_ test node]
+      (install! node version)
+      (configure! node)
+      (cu/start-daemon!
+        {:logfile logfile
+         :pidfile pidfile
+         :chdir base-dir
+         :env {:RUST_LOG "garage=debug,garage_api=trace"}}
+        binary
+        :server)
+      (c/exec :sleep 3)
+
+      (jepsen/synchronize test)
+      (connect-node! test node)
+
+      (jepsen/synchronize test)
+      (configure-node! test node)
+
+      (jepsen/synchronize test)
+      (when (= node (jepsen/primary test))
+        (finalize-config! node)))
+
+    (teardown! [_ test node]
+      (info node "tearing down garage" version)
+      (c/su
+        (cu/stop-daemon! binary pidfile)
+        (c/exec :rm :-rf logfile)
+        (c/exec :rm :-rf data-dir)
+        (c/exec :rm :-rf meta-dir)))
+
+    db/Pause
+    (pause! [_ test node]
+      (cu/grepkill! :stop binary))
+    (resume! [_ test node]
+      (cu/grepkill! :cont binary))
+
+    db/Kill
+    (kill! [_ test node]
+      (cu/stop-daemon! binary pidfile))
+    (start! [_ test node]
+      (cu/start-daemon!
+        {:logfile logfile
+         :pidfile pidfile
+         :chdir base-dir
+         :env {:RUST_LOG "garage=debug,garage_api=trace"}}
+        binary
+        :server))
+
+    db/LogFiles
+    (log-files [_ test node]
+      [logfile])))
+
+(defn creds
+  "Obtain Garage credentials for node"
+  [node]
+  {:access-key access-key-id
+   :secret-key secret-access-key
+   :endpoint (str "http://" node ":3900")
+   :bucket bucket-name
+   :client-config {:path-style-access-enabled true}})
+
diff --git a/script/jepsen.garage/src/jepsen/garage/nemesis.clj b/script/jepsen.garage/src/jepsen/garage/nemesis.clj
new file mode 100644
index 00000000..dfce0255
--- /dev/null
+++ b/script/jepsen.garage/src/jepsen/garage/nemesis.clj
@@ -0,0 +1,142 @@
+(ns jepsen.garage.nemesis
+  (:require [clojure.tools.logging :refer :all]
+            [jepsen [control :as c]
+             [core :as jepsen]
+             [generator :as gen]
+             [nemesis :as nemesis]]
+            [jepsen.nemesis.combined :as combined]
+            [jepsen.garage.daemon :as grg]
+            [jepsen.control.util :as cu]))
+
+; ---- reconfiguration nemesis ----
+
+(defn configure-present!
+  "Configure node to be active in new cluster layout"
+  [test nodes]
+  (info "configure-present!" nodes)
+  (let [node-ids (c/on-many nodes (c/exec grg/binary :node :id :-q))
+        node-id-strs (map (fn [[_ v]] (subs v  0 16)) node-ids)]
+    (c/on
+      (jepsen/primary test)
+      (apply c/exec (concat [grg/binary :layout :assign :-c :1G] node-id-strs)))))
+
+(defn configure-absent!
+  "Configure nodes to be active in new cluster layout"
+  [test nodes]
+  (info "configure-absent!" nodes)
+  (let [node-ids (c/on-many nodes (c/exec grg/binary :node :id :-q))
+        node-id-strs (map (fn [[_ v]] (subs v  0 16)) node-ids)]
+    (c/on
+      (jepsen/primary test)
+      (apply c/exec (concat [grg/binary :layout :assign :-g] node-id-strs)))))
+
+(defn finalize-config!
+  "Apply the proposed cluster layout"
+  [test]
+  (let [layout-show (c/on (jepsen/primary test) (c/exec grg/binary :layout :show))
+        [_ layout-next-version] (re-find #"apply --version (\d+)\n" layout-show)]
+    (if layout-next-version
+      (do
+        (info "layout show: " layout-show "; next-version: " layout-next-version)
+        (c/on (jepsen/primary test)
+              (c/exec grg/binary :layout :apply :--version layout-next-version)))
+      (info "no layout changes to apply"))))
+
+(defn reconfigure-subset
+  "Reconfigure cluster with only a subset of nodes"
+  [cnt]
+  (reify nemesis/Nemesis
+    (setup! [this test] this)
+
+    (invoke! [this test op] op
+      (case (:f op)
+        :start
+          (let [[keep-nodes remove-nodes]
+                (->> (:nodes test)
+                     shuffle
+                     (split-at cnt))]
+            (info "layout split: keep " keep-nodes ", remove " remove-nodes)
+            (configure-present! test keep-nodes)
+            (configure-absent! test remove-nodes)
+            (finalize-config! test)
+            (assoc op :value keep-nodes))
+        :stop
+          (do
+            (info "layout un-split: all nodes=" (:nodes test))
+            (configure-present! test (:nodes test))
+            (finalize-config! test)
+            (assoc op :value (:nodes test)))))
+
+    (teardown! [this test] this)))
+
+; ---- nemesis scenari ----
+
+(defn nemesis-op
+  "A generator for a single nemesis operation"
+  [op]
+  (fn [_ _] {:type :info, :f op}))
+
+(defn reconfiguration-package
+  "Cluster reconfiguration nemesis package"
+  [opts]
+  {:generator        (->>
+                       (gen/mix [(nemesis-op :reconfigure-start)
+                                 (nemesis-op :reconfigure-stop)])
+                       (gen/stagger (:interval opts 5)))
+   :final-generator  {:type :info, :f :reconfigure-stop}
+   :nemesis          (nemesis/compose
+                       {{:reconfigure-start :start
+                         :reconfigure-stop :stop} (reconfigure-subset 3)})
+   :perf              #{{:name  "reconfigure"
+                         :start #{:reconfigure-start}
+                         :stop  #{:reconfigur-stop}
+                         :color "#A197E9"}}})
+
+(defn scenario-c
+  "Clock modifying scenario"
+  [opts]
+  (combined/clock-package {:db (:db opts), :interval 1, :faults #{:clock}}))
+
+(defn scenario-cp
+  "Clock modifying + partition scenario"
+  [opts]
+  (combined/compose-packages
+    [(combined/clock-package {:db (:db opts), :interval 1, :faults #{:clock}})
+     (combined/partition-package {:db (:db opts), :interval 1, :faults #{:partition}})]))
+
+(defn scenario-r
+  "Cluster reconfiguration scenario"
+  [opts]
+  (reconfiguration-package {:interval 1}))
+
+(defn scenario-pr
+  "Partition + cluster reconfiguration scenario"
+  [opts]
+  (combined/compose-packages
+    [(combined/partition-package {:db (:db opts), :interval 1, :faults #{:partition}})
+     (reconfiguration-package {:interval 1})]))
+
+(defn scenario-cpr
+  "Clock scramble + partition + cluster reconfiguration scenario"
+  [opts]
+  (combined/compose-packages
+    [(combined/clock-package {:db (:db opts), :interval 1, :faults #{:clock}})
+     (combined/partition-package {:db (:db opts), :interval 1, :faults #{:partition}})
+     (reconfiguration-package {:interval 1})]))
+
+(defn scenario-cdp
+  "Clock modifying + db + partition scenario"
+  [opts]
+  (combined/compose-packages
+    [(combined/clock-package {:db (:db opts), :interval 1, :faults #{:clock}})
+     (combined/db-package {:db (:db opts), :interval 1, :faults #{:db :pause :kill}})
+     (combined/partition-package {:db (:db opts), :interval 1, :faults #{:partition}})]))
+
+(defn scenario-dpr
+  "Db + partition + cluster reconfiguration scenario"
+  [opts]
+  (combined/compose-packages
+    [(combined/db-package {:db (:db opts), :interval 1, :faults #{:db :pause :kill}})
+     (combined/partition-package {:db (:db opts), :interval 1, :faults #{:partition}})
+     (reconfiguration-package {:interval 1})]))
+
diff --git a/script/jepsen.garage/src/jepsen/garage/reg.clj b/script/jepsen.garage/src/jepsen/garage/reg.clj
new file mode 100644
index 00000000..39708c0b
--- /dev/null
+++ b/script/jepsen.garage/src/jepsen/garage/reg.clj
@@ -0,0 +1,143 @@
+(ns jepsen.garage.reg
+  (:require [clojure.tools.logging :refer :all]
+            [clojure.string :as str]
+            [clojure.set :as set]
+            [jepsen [checker :as checker]
+             [cli :as cli]
+             [client :as client]
+             [control :as c]
+             [db :as db]
+             [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]
+            [jepsen.os.debian :as debian]
+            [jepsen.garage.daemon :as grg]
+            [jepsen.garage.s3api :as s3]
+            [knossos.model :as model]
+            [slingshot.slingshot :refer [try+]]))
+
+(defn op-get [_ _] {:type :invoke, :f :read, :value nil})
+(defn op-put [_ _] {:type :invoke, :f :write, :value (str (rand-int 99))})
+(defn op-del [_ _] {:type :invoke, :f :write, :value nil})
+
+(defrecord RegClient [creds]
+  client/Client
+  (open! [this test node]
+    (assoc this :creds (grg/creds node)))
+  (setup! [this test])
+  (invoke! [this test op]
+    (try+
+      (let [[k v] (:value op)]
+        (case (:f op)
+          :read
+            (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))))
+          :write
+            (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 :info, :error ::unavailable))
+      (catch (re-find #"Broken pipe" (.getMessage %)) ex
+        (assoc op :type :info, :error ::broken-pipe))
+      (catch (re-find #"Connection refused" (.getMessage %)) ex
+        (assoc op :type :info, :error ::connection-refused))))
+  (teardown! [this test])
+  (close! [this test]))
+
+(defn reg-read-after-write
+  "Read-after-Write checker for register operations"
+  []
+  (reify checker/Checker
+    (check [this test history opts]
+      (let [init {:put-values {-1 nil}
+                  :put-done #{-1}
+                  :put-in-progress {}
+                  :read-can-contain {}
+                  :bad-reads #{}}
+            final (reduce
+                    (fn [state op]
+                      (let [current-values (set/union
+                                             (set (map (fn [idx] (get (:put-values state) idx)) (:put-done state)))
+                                             (set (map (fn [[_ [idx _]]] (get (:put-values state) idx)) (:put-in-progress state))))
+                            read-can-contain (reduce
+                                               (fn [rcc [idx v]] (assoc rcc idx (set/union current-values v)))
+                                               {} (:read-can-contain state))]
+                      (info "--------")
+                      (info "state: " state)
+                      (info "current-values: " current-values)
+                      (info "read-can-contain: " read-can-contain)
+                      (info "op: " op)
+                      (case [(:type op) (:f op)]
+                        ([:invoke :write])
+                          (assoc state
+                                 :read-can-contain read-can-contain
+                                 :put-values (assoc (:put-values state) (:index op) (:value op))
+                                 :put-in-progress (assoc (:put-in-progress state) (:process op) [(:index op) (:put-done state)]))
+                        ([:ok :write])
+                          (let [[index overwrites] (get (:put-in-progress state) (:process op))]
+                            (assoc state
+                                   :read-can-contain read-can-contain
+                                   :put-in-progress (dissoc (:put-in-progress state) (:process op))
+                                   :put-done
+                                     (conj
+                                       (set/difference (:put-done state) overwrites)
+                                       index)))
+                        ([:invoke :read])
+                         (assoc state
+                                :read-can-contain (assoc read-can-contain (:process op) current-values))
+                        ([:ok :read])
+                         (let [this-read-can-contain (get read-can-contain (:process op))
+                               bad-reads (if (contains? this-read-can-contain (:value op))
+                                           (:bad-reads state)
+                                           (conj (:bad-reads state) [(:process op) (:index op) (:value op) this-read-can-contain]))]
+                           (info "this-read-can-contain: " this-read-can-contain)
+                           (assoc state
+                                  :read-can-contain (dissoc read-can-contain (:process op))
+                                  :bad-reads bad-reads))
+                        state)))
+                    init history)
+            valid? (empty? (:bad-reads final))]
+        (assoc final :valid? valid?)))))
+
+(defn workload-common
+  "Common parts of workload"
+  [opts]
+  {:client           (RegClient. nil)
+   :generator        (independent/concurrent-generator
+                       10
+                       (range)
+                       (fn [k]
+                         (->>
+                           (gen/mix [op-get op-put op-del])
+                           (gen/limit (:ops-per-key opts)))))})
+
+(defn workload1
+  "Tests linearizable reads and writes"
+  [opts]
+  (assoc (workload-common opts)
+         :checker (independent/checker
+                    (checker/compose
+                      {:linear (checker/linearizable
+                                 {:model     (model/register)
+                                  :algorithm :linear})
+                       :timeline (timeline/html)}))))
+
+(defn workload2
+  "Tests CRDT reads and writes"
+  [opts]
+  (assoc (workload-common opts)
+         :checker (independent/checker
+                    (checker/compose
+                      {:reg-read-after-write (reg-read-after-write)
+                       :timeline (timeline/html)}))))
diff --git a/script/jepsen.garage/src/jepsen/garage/s3api.clj b/script/jepsen.garage/src/jepsen/garage/s3api.clj
new file mode 100644
index 00000000..531e0157
--- /dev/null
+++ b/script/jepsen.garage/src/jepsen/garage/s3api.clj
@@ -0,0 +1,48 @@
+(ns jepsen.garage.s3api
+  (:require [clojure.tools.logging :refer :all]
+            [jepsen [control :as c]]
+            [amazonica.aws.s3 :as s3]
+            [slingshot.slingshot :refer [try+]]))
+
+; GARAGE S3 HELPER FUNCTIONS
+
+(defn get
+  "Helper for GetObject"
+  [creds k]
+  (try+
+    (-> (s3/get-object creds (:bucket creds) k)
+        :input-stream
+        slurp)
+    (catch (re-find #"Key not found" (.getMessage %)) ex
+      nil)))
+
+(defn put
+  "Helper for PutObject or DeleteObject (is a delete if value is nil)"
+  [creds k v]
+  (if (= v nil)
+    (s3/delete-object creds
+                      :bucket-name (:bucket creds)
+                      :key k)
+    (let [some-bytes (.getBytes v "UTF-8")
+          bytes-stream (java.io.ByteArrayInputStream. some-bytes)]
+      (s3/put-object creds
+                     :bucket-name (:bucket creds)
+                     :key k
+                     :input-stream bytes-stream
+                     :metadata {:content-length (count some-bytes)}))))
+
+(defn list-inner [creds prefix ct accum]
+  (let [list-result (s3/list-objects-v2 creds
+                                        {:bucket-name (:bucket creds)
+                                         :prefix prefix
+                                         :continuation-token ct})
+        new-object-summaries (:object-summaries list-result)
+        new-objects (map (fn [d] (:key d)) new-object-summaries)
+        objects (concat new-objects accum)]
+    (if (:truncated? list-result)
+      (list-inner creds prefix (:next-continuation-token list-result) objects)
+      objects)))
+(defn list
+  "Helper for ListObjects -- just lists everything in the bucket"
+  [creds prefix]
+  (list-inner creds prefix nil []))
diff --git a/script/jepsen.garage/src/jepsen/garage/set.clj b/script/jepsen.garage/src/jepsen/garage/set.clj
new file mode 100644
index 00000000..2c7a2ccd
--- /dev/null
+++ b/script/jepsen.garage/src/jepsen/garage/set.clj
@@ -0,0 +1,135 @@
+(ns jepsen.garage.set
+  (:require [clojure.tools.logging :refer :all]
+            [clojure.string :as str]
+            [clojure.set :as set]
+            [jepsen [checker :as checker]
+             [cli :as cli]
+             [client :as client]
+             [control :as c]
+             [checker :as checker]
+             [db :as db]
+             [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]
+            [jepsen.os.debian :as debian]
+            [jepsen.garage.daemon :as grg]
+            [jepsen.garage.s3api :as s3]
+            [knossos.model :as model]
+            [slingshot.slingshot :refer [try+]]))
+
+(defn op-add-rand100 [_ _] {:type :invoke, :f :add, :value (rand-int 100)})
+(defn op-read [_ _] {:type :invoke, :f :read, :value nil})
+
+(defrecord SetClient [creds]
+  client/Client
+  (open! [this test node]
+    (assoc this :creds (grg/creds node)))
+  (setup! [this test])
+  (invoke! [this test op]
+    (try+
+      (let [[k v] (:value op)
+            prefix (str "set" k "/")]
+        (case (:f op)
+          :add
+            (util/timeout
+              10000
+              (assoc op :type :info, :error ::timeout)
+              (do
+                (s3/put (:creds this) (str prefix v) "present")
+                (assoc op :type :ok)))
+          :read
+            (util/timeout
+              10000
+              (assoc op :type :fail, :error ::timeout)
+              (do
+                (let [items (s3/list (:creds this) prefix)]
+                  (let [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))))))))
+      (catch (re-find #"Unavailable" (.getMessage %)) ex
+        (assoc op :type :info, :error ::unavailable))
+      (catch (re-find #"Broken pipe" (.getMessage %)) ex
+        (assoc op :type :info, :error ::broken-pipe))
+      (catch (re-find #"Connection refused" (.getMessage %)) ex
+        (assoc op :type :info, :error ::connection-refused))))
+  (teardown! [this test])
+  (close! [this test]))
+
+(defn set-read-after-write
+  "Read-after-Write checker for set operations"
+  []
+  (reify checker/Checker
+    (check [this test history opts]
+      (let [init {:add-started #{}
+                  :add-done #{}
+                  :read-must-contain {}
+                  :missed #{}
+                  :unexpected #{}}
+            final (reduce
+                    (fn [state op]
+                      (case [(:type op) (:f op)]
+                        ([:invoke :add])
+                          (assoc state :add-started (conj (:add-started state) (:value op)))
+                        ([:ok :add])
+                          (assoc state :add-done (conj (:add-done state) (:value op)))
+                        ([:invoke :read])
+                          (assoc-in state [:read-must-contain (:process op)] (:add-done state))
+                        ([:ok :read])
+                          (let [read-must-contain (get (:read-must-contain state) (:process op))
+                                new-missed (set/difference read-must-contain (:value op))
+                                new-unexpected (set/difference (:value op) (:add-started state))]
+                            (assoc state
+                                   :read-must-contain (dissoc (:read-must-contain state) (:process op))
+                                   :missed (set/union (:missed state) new-missed),
+                                   :unexpected (set/union (:unexpected state) new-unexpected)))
+                         state))
+                    init history)
+            valid? (and (empty? (:missed final)) (empty? (:unexpected final)))]
+        (assoc final :valid? valid?)))))
+
+(defn workload1
+  "Tests insertions and deletions"
+  [opts]
+  {:client            (SetClient. nil)
+   :checker           (independent/checker
+                        (checker/compose
+                          {:set (checker/set)
+                           :timeline (timeline/html)}))
+   :generator         (independent/concurrent-generator
+                        10
+                        (range 100)
+                        (fn [k]
+                          (->> (range)
+                           (map (fn [x] {:type :invoke, :f :add, :value x}))
+                           (gen/limit (:ops-per-key opts)))))
+   :final-generator   (independent/concurrent-generator
+                        10
+                        (range 100)
+                        (fn [k]
+                          (gen/phases
+                            (gen/once op-read)
+                            (gen/sleep 5))))})
+
+(defn workload2
+  "Tests insertions and deletions"
+  [opts]
+  {:client            (SetClient. nil)
+   :checker           (independent/checker
+                        (checker/compose
+                          {:set-read-after-write (set-read-after-write)
+                           ; :set-full (checker/set-full {:linearizable? false})
+                           :timeline (timeline/html)}))
+   :generator         (independent/concurrent-generator
+                        10
+                        (range)
+                        (fn [k]
+                          (->> (gen/mix [op-add-rand100 op-read])
+                               (gen/limit (:ops-per-key opts)))))})
+
+