[Tarantool-patches] [PATCH v2] test: fix hang of vinyl/select_consistency.* test

["Alexander V. Tikhonov" <avtikhon@tarantool.org>]

During testing process:

  https://gitlab.com/tarantool/tarantool/-/jobs/800863457#L5303

found that test vinyl/select_consistency.test.lua hanged:

  --- vinyl/select_consistency.result		Thu Jun 11 11:59:48 2020
  +++ var/152_vinyl/select_consistency.result	Tue Oct 20 09:13:02 2020
  @@ -137,16 +137,3 @@
   for i = 1, ch:size() do
       ch:get()
   end;
  ----
  -...
  -test_run:cmd("setopt delimiter ''");
  ----
  -- true
  -...

This issue stops the testing till the complete timeout of the test-run
will stop all the testing process.

Also found that real hang occured at box.snapshot command in snap_loop
loop, like:

  [001] Last 15 lines of Tarantool Log file [Instance "vinyl"][/source/test/var/001_vinyl/vinyl.log]:
  [001] 2020-11-15 18:13:49.928 [78887] main/105/gc I> removed /source/test/var/001_vinyl/vinyl/519/2/00000000000000011145.run
  [001] 2020-11-15 18:13:49.928 [78887] vinyl.dump.0/640/task I> writing `/source/test/var/001_vinyl/vinyl/519/0/00000000000000011538.index'
  [001] 2020-11-15 18:13:49.928 [78887] snapshot/101/main I> done
  [001] 2020-11-15 18:13:49.929 [78887] main/105/gc I> removed /source/test/var/001_vinyl/vinyl/519/2/00000000000000011157.index
  [001] 2020-11-15 18:13:49.929 [78887] main/108/vinyl.scheduler I> 519/0: dump completed
  [001] 2020-11-15 18:13:49.929 [78887] main/108/vinyl.scheduler I> dumped 0 bytes in 0.0 s, rate 0.0 MB/s
  [001] 2020-11-15 18:13:49.929 [78887] main/481/lua I> vinyl checkpoint completed
  [001] 2020-11-15 18:13:49.929 [78887] main/105/gc I> removed /source/test/var/001_vinyl/vinyl/519/2/00000000000000011157.run
  [001] 2020-11-15 18:13:49.929 [78887] main/108/vinyl.scheduler I> 519/0: started compacting range ([94]..inf), runs 2/2
  [001] 2020-11-15 18:13:49.930 [78887] wal I> removed /source/test/var/001_vinyl/vinyl/00000000000000093070.xlog
  [001] 2020-11-15 18:13:49.930 [78887] main/105/gc I> removed /source/test/var/001_vinyl/vinyl/00000000000000094030.snap.inprogress
  [001] 2020-11-15 18:13:49.930 [78887] main I> removed /source/test/var/001_vinyl/vinyl/00000000000000093306.snap
  [001] 2020-11-15 18:13:49.930 [78887] main I> removed /source/test/var/001_vinyl/vinyl/00000000000000093070.vylog
  [001] 2020-11-15 18:13:49.931 [78887] main/481/lua F> can't rename .snap.inprogress
  [001] 2020-11-15 18:13:49.931 [78887] main/481/lua F> can't rename .snap.inprogress

It happened because on heavy loaded hosts may occure the situation
when the previous snapshot was inprogress when the new snapshot came
with the same file name *.snap.inprogress. It happens before the
current snapshot completed and printed "dump completed" in log file.
Also this file *.snap.inprogress was seen left on manual debug, when
the test hanged before this patch. To resolve the test issue fiber
sleep delay after it can be increased, but we want to save the issue
reproducable. The current patch corrects the test to avoid of hang on
box snapshot, to be able to continue testing after it failed.

Needed for #4385
---

Github: https://github.com/tarantool/tarantool/tree/avtikhon/gh-4385_hang_select_consistency
Issue: https://github.com/tarantool/tarantool/issues/4385

 test/vinyl/select_consistency.result   | 67 ++++++++++++++++++++------
 test/vinyl/select_consistency.test.lua | 61 ++++++++++++++++++-----
 test/vinyl/suite.ini                   |  3 +-
 3 files changed, 103 insertions(+), 28 deletions(-)

diff --git a/test/vinyl/select_consistency.result b/test/vinyl/select_consistency.result
index f27d0ec68..9a65ba4c5 100644
--- a/test/vinyl/select_consistency.result
+++ b/test/vinyl/select_consistency.result
@@ -4,6 +4,9 @@ test_run = require('test_run').new()
 fiber = require 'fiber'
 ---
 ...
+log = require 'log'
+---
+...
 math.randomseed(os.time())
 ---
 ...
@@ -52,6 +55,8 @@ function gen_update()
 end;
 ---
 ...
+failed = false
+
 function dml_loop()
     local insert = true
     while not stop do
@@ -75,8 +80,18 @@ end;
 ...
 function snap_loop()
     while not stop do
-        box.snapshot()
-        fiber.sleep(0.1)
+        local ok = fiber.create(function()
+            local ok, err = pcall(box.snapshot)
+            if ok == false then
+                log.error("error: box.snapshot failed with error " .. err)
+            end
+            return ok
+        end)
+        if ok == false then
+            failed = true
+            break
+        end
+        fiber.sleep(0.5)
     end
     ch:put(true)
 end;
@@ -97,10 +112,7 @@ _ = fiber.create(dml_loop);
 _ = fiber.create(snap_loop);
 ---
 ...
-failed = {};
----
-...
-for i = 1, 10000 do
+function select_loop()
     local val = math.random(MAX_VAL)
     box.begin()
     local res1 = s.index.i1:select({val})
@@ -117,25 +129,48 @@ for i = 1, 10000 do
                 end
             end
             if not found then
+                log.error("error: equal not found for res1 and res2:")
+                local ts1 = ''
+                local ts2 = ''
+                for _, t1 in ipairs(res1) do
+                    ts1 = ts1 .. " " .. t1[1]
+                end
+                log.info("error: equal not found for res1" .. ts1)
+                for _, t2 in ipairs(res2) do
+                    ts2 = ts2 .. " " .. t2[1]
+                end
+                log.info("error: equal not found for res2" .. ts2)
                 equal = false
                 break
             end
         end
-    else
-        equal = false
-    end
-    if not equal then
-        table.insert(failed, {res1, res2})
     end
     fiber.sleep(0)
+    return equal
+end;
+---
+...
+for i = 1, 10000 do
+    if failed or not select_loop(i) then
+        log.error("error: failed on iteration " .. i)
+        failed = true
+        break
+    end
 end;
 ---
 ...
 stop = true;
 ---
 ...
-for i = 1, ch:size() do
-    ch:get()
+CHANNEL_GET_TIMEOUT = 10
+function check_get()
+    for i = 1, ch:size() do
+        if ch:get(CHANNEL_GET_TIMEOUT) == nil then
+            log.error("error: hanged on ch:get() on iteration " .. i)
+            return false
+        end
+    end
+    return true
 end;
 ---
 ...
@@ -143,10 +178,14 @@ test_run:cmd("setopt delimiter ''");
 ---
 - true
 ...
-#failed == 0 or failed
+check_get()
 ---
 - true
 ...
+failed
+---
+- false
+...
 s:drop()
 ---
 ...
diff --git a/test/vinyl/select_consistency.test.lua b/test/vinyl/select_consistency.test.lua
index 73b443e89..2766e2884 100644
--- a/test/vinyl/select_consistency.test.lua
+++ b/test/vinyl/select_consistency.test.lua
@@ -1,6 +1,7 @@
 test_run = require('test_run').new()
 
 fiber = require 'fiber'
+log = require 'log'
 
 math.randomseed(os.time())
 
@@ -33,6 +34,8 @@ function gen_update()
     pcall(s.update, s, math.random(MAX_KEY), {{'+', 5, 1}})
 end;
 
+failed = false
+
 function dml_loop()
     local insert = true
     while not stop do
@@ -55,8 +58,18 @@ end;
 
 function snap_loop()
     while not stop do
-        box.snapshot()
-        fiber.sleep(0.1)
+        local ok = fiber.create(function()
+            local ok, err = pcall(box.snapshot)
+            if ok == false then
+                log.error("error: box.snapshot failed with error " .. err)
+            end
+            return ok
+        end)
+        if ok == false then
+            failed = true
+            break
+        end
+        fiber.sleep(0.5)
     end
     ch:put(true)
 end;
@@ -68,9 +81,7 @@ _ = fiber.create(dml_loop);
 _ = fiber.create(dml_loop);
 _ = fiber.create(snap_loop);
 
-failed = {};
-
-for i = 1, 10000 do
+function select_loop()
     local val = math.random(MAX_VAL)
     box.begin()
     local res1 = s.index.i1:select({val})
@@ -87,26 +98,50 @@ for i = 1, 10000 do
                 end
             end
             if not found then
+                log.error("error: equal not found for res1 and res2:")
+                local ts1 = ''
+                local ts2 = ''
+                for _, t1 in ipairs(res1) do
+                    ts1 = ts1 .. " " .. t1[1]
+                end
+                log.info("error: equal not found for res1" .. ts1)
+                for _, t2 in ipairs(res2) do
+                    ts2 = ts2 .. " " .. t2[1]
+                end
+                log.info("error: equal not found for res2" .. ts2)
                 equal = false
                 break
             end
         end
-    else
-        equal = false
-    end
-    if not equal then
-        table.insert(failed, {res1, res2})
     end
     fiber.sleep(0)
+    return equal
+end;
+
+for i = 1, 10000 do
+    if failed or not select_loop(i) then
+        log.error("error: failed on iteration " .. i)
+        failed = true
+        break
+    end
 end;
 
 stop = true;
-for i = 1, ch:size() do
-    ch:get()
+
+CHANNEL_GET_TIMEOUT = 10
+function check_get()
+    for i = 1, ch:size() do
+        if ch:get(CHANNEL_GET_TIMEOUT) == nil then
+            log.error("error: hanged on ch:get() on iteration " .. i)
+            return false
+        end
+    end
+    return true
 end;
 
 test_run:cmd("setopt delimiter ''");
 
-#failed == 0 or failed
+check_get()
+failed
 
 s:drop()
diff --git a/test/vinyl/suite.ini b/test/vinyl/suite.ini
index 93d1b3cf6..4780107f8 100644
--- a/test/vinyl/suite.ini
+++ b/test/vinyl/suite.ini
@@ -23,7 +23,8 @@ fragile = {
             "issues": [ "gh-4346" ]
         },
         "select_consistency.test.lua": {
-            "issues": [ "gh-4385" ]
+            "issues": [ "gh-4385" ],
+            "checksums": [ "94d5359d451ee7bfdb35a037f80b14ff", "f7e8ebc72f4d59941b4ca10fde474963", "a87a5ddbe2745fff52eac372db610699" ]
         },
         "throttle.test.lua": {
             "issues": [ "gh-4168" ]
-- 
2.25.1