From ef662822c9e48ff7cfd9300590617e089c0a9498 Mon Sep 17 00:00:00 2001 From: Alex Auvolat Date: Thu, 19 Oct 2023 23:40:55 +0200 Subject: jepsen: fix the list-objects call (?) --- script/jepsen.garage/README.md | 37 +++++++++++++++++++----- script/jepsen.garage/src/jepsen/garage/s3api.clj | 27 ++++++++--------- script/jepsen.garage/src/jepsen/garage/set.clj | 16 +++++----- 3 files changed, 52 insertions(+), 28 deletions(-) diff --git a/script/jepsen.garage/README.md b/script/jepsen.garage/README.md index f6fb3a59..8dcd3766 100644 --- a/script/jepsen.garage/README.md +++ b/script/jepsen.garage/README.md @@ -33,7 +33,7 @@ lein run test --nodes-file nodes.vagrant --time-limit 64 --rate 50 --concurrenc ## Results -**Register linear, without timestamp patch** +### 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` @@ -43,7 +43,7 @@ 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** +### 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` @@ -54,24 +54,45 @@ Results: 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 +### Read-after-write CRDT register model -**Set, basic test** +TODO: determine the expected semantics of such a register, code a checker and show that results are correct -Command: `lein run test --nodes-file nodes.vagrant --time-limit 60 --rate 20 --concurrency 20 --workload set1 --ops-per-key 100` +### Set, basic test (write some items, then read) + +Command: `lein run test --nodes-file nodes.vagrant --time-limit 60 --rate 100 --concurrency 100 --workload set1 --ops-per-key 100` Results: -- ListObjects returns objects not within prefix???? -> BAD, definitely a bug, but maybe it's in the instrumentation code? +- For now, no failures with clock-scramble nemesis + partition nemesis + +### Set, continuous test (interspersed reads and writes) + +TODO + +TODO: nemesis that reconfigures the cluster with a different subset of nodes, to have requests that occur during a resync period. + + +## Investigating (and fixing) wierd behavior + +### Segfaults + +They are due to the download being interrupted in the middle (^C during first launch on clean VMs), the `garage` binary is truncated. +Add `:force?` to the `cached-wget!` call in `daemon.clj` to re-download the binary. + +### In `jepsen.garage`: prefix wierdness In `store/garage set1/20231019T163358.615+0200`: ``` INFO [2023-10-19 16:35:20,977] clojure-agent-send-off-pool-207 - jepsen.garage.set list results for prefix set20/ : (set13/0 set13/1 set13/10 set13/11 set13/12 set13/13 set13/14 set13/15 set13/16 set13/17 set13/18 set13/19 set13/2 set13/20 set13/21 set13/22 set13/23 set13/24 set13/25 set13/26 set13/27 set13/28 set13/29 set13/3 set13/30 set13/31 set13/32 set13/33 set13/34 set13/35 set13/36 set13/37 set13/38 set13/39 set13/4 set13/40 set13/41 set13/42 set13/43 set13/44 set13/45 set13/46 set13/47 set13/48 set13/49 set13/5 set13/50 set13/51 set13/52 set13/53 set13/54 set13/55 set13/56 set13/57 set13/58 set13/59 set13/6 set13/60 set13/61 set13/62 set13/63 set13/64 set13/65 set13/66 set13/67 set13/68 set13/69 set13/7 set13/70 set13/71 set13/72 set13/73 set13/74 set13/75 set13/76 set13/77 set13/78 set13/79 set13/8 set13/80 set13/81 set13/82 set13/83 set13/84 set13/85 set13/86 set13/87 set13/88 set13/89 set13/9 set13/90 set13/91 set13/92 set13/93 set13/94 set13/95 set13/96 set13/97 set13/98 set13/99) (node: http://192.168.56.25:3900 ) - ``` -- Sometimes ListObjects returns an empty list???? -> BAD, quorums should ensure this doesn't happen +After inspecting, the actual S3 call made was with prefix "set13/", so at least this is not an error in Garage itself but in the jepsen code. + +Finally found out that this was due to closures not correctly capturing their context in the list function in s3api.clj (wtf clojure?) +Not sure exactly where it came from but it seems to have been fixed by making list-inner a separate function and not a sub-function, +and passing all values that were previously in the context (creds and prefix) as additional arguments. ## License diff --git a/script/jepsen.garage/src/jepsen/garage/s3api.clj b/script/jepsen.garage/src/jepsen/garage/s3api.clj index 977de7dc..4f292ac0 100644 --- a/script/jepsen.garage/src/jepsen/garage/s3api.clj +++ b/script/jepsen.garage/src/jepsen/garage/s3api.clj @@ -31,19 +31,20 @@ :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)] + (info (:endpoint creds) "ListObjectsV2 prefix(" prefix "), ct(" ct "): " new-objects) + (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] - (defn list-inner [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)] - (info (:endpoint creds) "ListObjectsV2 prefix(" prefix "), ct(" ct "): " new-objects) - (if (:truncated? list-result) - (list-inner (:next-continuation-token list-result) objects) - objects))) - (list-inner nil [])) + (info "in s3/list creds:" creds ", prefix:" 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 index 8a1ab83f..c5387462 100644 --- a/script/jepsen.garage/src/jepsen/garage/set.clj +++ b/script/jepsen.garage/src/jepsen/garage/set.clj @@ -44,13 +44,15 @@ (util/timeout 10000 (assoc op :type :fail, :error ::timeout) - (let [items (s3/list (:creds this) prefix)] - (info "list results for prefix" prefix ":" items " (node:" (:endpoint (:creds this)) ")") - (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)))))))) + (do + (info "call s3/list creds: " (:creds this) ", prefix:" prefix) + (let [items (s3/list (:creds this) prefix)] + (info "list results for prefix" prefix ":" items " (node:" (:endpoint (:creds this)) ")") + (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))))))))) (teardown! [this test]) (close! [this test])) -- cgit v1.2.3