[Tarantool-patches] [PATCH] net.box: drop conn:timeout()

[Tarantool-patches] [PATCH] net.box: drop conn:timeout()

[Vladimir Davydov via Tarantool-patches]

conn:timeout(timeout) writes (now + timeout) to conn._deadlines table
keyed by fiber.self(). The deadline will then be used by all conn
methods unless specified explicitly in the options argument.

Usage of fiber.self() degrades net.box performance by about 15% in case
timeout is not specified, because it is a C call and so interferes with
JIT. See the ticket for the test details.

Since the feature is unusable and was deprecated more than four years
ago (in 1.7.4) in favor of specifying timeout in the options argument
(see commit 58da206c33197), it should be fine to drop it.

Closes #6242
---
 .../gh-6242-net-box-drop-conn-timeout.md      |  9 ++++
 src/box/lua/net_box.lua                       | 26 ----------
 .../net.box_count_inconsistent_gh-3262.result | 49 -------------------
 ...et.box_count_inconsistent_gh-3262.test.lua | 20 --------
 4 files changed, 9 insertions(+), 95 deletions(-)
 create mode 100644 changelogs/unreleased/gh-6242-net-box-drop-conn-timeout.md

diff --git a/changelogs/unreleased/gh-6242-net-box-drop-conn-timeout.md b/changelogs/unreleased/gh-6242-net-box-drop-conn-timeout.md
new file mode 100644
index 000000000000..69d12fb858e5
--- /dev/null
+++ b/changelogs/unreleased/gh-6242-net-box-drop-conn-timeout.md
@@ -0,0 +1,9 @@
+## feature/core
+
+* **[Breaking change]** timeout() method of net.box connection, which was
+  marked deprecated more than four years ago (in 1.7.4) was dropped, because
+  it negatively affected performance of hot net.box methods, like call() and
+  select(), in case those are called without specifying a timeout.
+
+---
+Breaking change: timeout() method of net.box connection was dropped.
diff --git a/src/box/lua/net_box.lua b/src/box/lua/net_box.lua
index 3878abf21914..15e6c093cc15 100644
--- a/src/box/lua/net_box.lua
+++ b/src/box/lua/net_box.lua
@@ -1047,9 +1047,6 @@ local function new_sm(host, port, opts, connection, greeting)
         setmetatable(remote, console_mt)
     else
         setmetatable(remote, remote_mt)
-        -- @deprecated since 1.7.4
-        remote._deadlines = setmetatable({}, {__mode = 'k'})
-
         remote._space_mt = space_metatable(remote)
         remote._index_mt = index_metatable(remote)
         if opts.call_16 then
@@ -1176,17 +1173,11 @@ function remote_methods:_request(method, opts, request_ctx, ...)
             return res
         end
         if opts.timeout then
-            -- conn.space:request(, { timeout = timeout })
             deadline = fiber_clock() + opts.timeout
-        else
-            -- conn:timeout(timeout).space:request()
-            -- @deprecated since 1.7.4
-            deadline = self._deadlines[fiber_self()]
         end
         on_push = opts.on_push or on_push_sync_default
         on_push_ctx = opts.on_push_ctx
     else
-        deadline = self._deadlines[fiber_self()]
         on_push = on_push_sync_default
     end
     -- Execute synchronous request.
@@ -1289,28 +1280,11 @@ end
 
 function remote_methods:wait_state(state, timeout)
     check_remote_arg(self, 'wait_state')
-    if timeout == nil then
-        local deadline = self._deadlines[fiber_self()]
-        timeout = deadline and max(0, deadline - fiber_clock())
-    end
     return self._transport.wait_state(state, timeout)
 end
 
 local compat_warning_said = false
 
--- @deprecated since 1.7.4
-function remote_methods:timeout(timeout)
-    check_remote_arg(self, 'timeout')
-    if not compat_warning_said then
-        compat_warning_said = true
-        log.warn("netbox:timeout(timeout) is deprecated since 1.7.4, "..
-                 "please use space:<request>(..., {timeout = t}) instead.")
-    end
-    -- Sic: this is broken by design
-    self._deadlines[fiber_self()] = (timeout and fiber_clock() + timeout)
-    return self
-end
-
 function remote_methods:_install_schema(schema_version, spaces, indices,
                                         collations)
     local sl, space_mt, index_mt = {}, self._space_mt, self._index_mt
diff --git a/test/box/net.box_count_inconsistent_gh-3262.result b/test/box/net.box_count_inconsistent_gh-3262.result
index c77677625d97..286f9ded8aea 100644
--- a/test/box/net.box_count_inconsistent_gh-3262.result
+++ b/test/box/net.box_count_inconsistent_gh-3262.result
@@ -427,55 +427,6 @@ cn:eval('return ret_after(...)', {1.00}, { timeout = 1e-9 })
 ---
 - error: Timeout exceeded
 ...
---
--- :timeout()
--- @deprecated since 1.7.4
---
-cn:timeout(1).space.net_box_test_space.index.primary:select{234}
----
-- - [234, 1, 2, 3]
-...
-cn:call('ret_after', {.01})
----
-- [[0.01]]
-...
-cn:timeout(1):call('ret_after', {.01})
----
-- [[0.01]]
-...
-cn:timeout(.01):call('ret_after', {1})
----
-- error: Timeout exceeded
-...
-cn = remote:timeout(0.0000000001):connect(LISTEN.host, LISTEN.service, { user = 'netbox', password = '123' })
----
-...
-cn:close()
----
-...
-cn = remote:timeout(1):connect(LISTEN.host, LISTEN.service, { user = 'netbox', password = '123' })
----
-...
-remote.self:ping()
----
-- true
-...
-remote.self.space.net_box_test_space:select{234}
----
-- - [234, 1, 2, 3]
-...
-remote.self:timeout(123).space.net_box_test_space:select{234}
----
-- - [234, 1, 2, 3]
-...
-remote.self:is_connected()
----
-- true
-...
-remote.self:wait_connected()
----
-- true
-...
 cn:close()
 ---
 ...
diff --git a/test/box/net.box_count_inconsistent_gh-3262.test.lua b/test/box/net.box_count_inconsistent_gh-3262.test.lua
index e84e85cf3829..a6d87cdcc830 100644
--- a/test/box/net.box_count_inconsistent_gh-3262.test.lua
+++ b/test/box/net.box_count_inconsistent_gh-3262.test.lua
@@ -155,26 +155,6 @@ cn:call('ret_after', {1.00}, { timeout = 1e-9 })
 cn:eval('return ret_after(...)', {0.01}, { timeout = 1.00 })
 cn:eval('return ret_after(...)', {1.00}, { timeout = 1e-9 })
 
---
--- :timeout()
--- @deprecated since 1.7.4
---
-
-cn:timeout(1).space.net_box_test_space.index.primary:select{234}
-cn:call('ret_after', {.01})
-cn:timeout(1):call('ret_after', {.01})
-cn:timeout(.01):call('ret_after', {1})
-
-cn = remote:timeout(0.0000000001):connect(LISTEN.host, LISTEN.service, { user = 'netbox', password = '123' })
-cn:close()
-cn = remote:timeout(1):connect(LISTEN.host, LISTEN.service, { user = 'netbox', password = '123' })
-
-remote.self:ping()
-remote.self.space.net_box_test_space:select{234}
-remote.self:timeout(123).space.net_box_test_space:select{234}
-remote.self:is_connected()
-remote.self:wait_connected()
-
 cn:close()
 -- cleanup database after tests
 space:drop()
-- 
2.25.1

Re: [Tarantool-patches] [PATCH] net.box: drop conn:timeout()

[Vladislav Shpilevoy via Tarantool-patches]

Hi! Thanks for the patch!

I hope I was supposed to review this. Could you please add the
reviewers into CC/To for next patches?

See 5 comments below.

On 26.07.2021 12:58, Vladimir Davydov via Tarantool-patches wrote:
> conn:timeout(timeout) writes (now + timeout) to conn._deadlines table
> keyed by fiber.self(). The deadline will then be used by all conn
> methods unless specified explicitly in the options argument.
> 
> Usage of fiber.self() degrades net.box performance by about 15% in case
> timeout is not specified, because it is a C call and so interferes with
> JIT. See the ticket for the test details.
> 
> Since the feature is unusable and was deprecated more than four years
> ago (in 1.7.4) in favor of specifying timeout in the options argument
> (see commit 58da206c33197), it should be fine to drop it.

1. Is it possible to add the commit title after the hash in quotes and
parentheses? Like this:

	(see commit 58da206c33197 ("net.box: add { timeout = } option to requests"))

It helps to quickly understand what was the commit about without
copy-pasting the hash for `git show`.
https://github.com/tarantool/tarantool/wiki/Code-review-procedure#commit-message

> Closes #6242
> ---

2. May I ask you please to push the patch onto a branch and attach the
issue and branch links after `---` in the first/cover email? For next
patches and for this one too. It simplifies the review; makes your patch
pass CI before the review (or not pass); and simplifies patch push in the
end.
https://github.com/tarantool/tarantool/wiki/Code-review-procedure#sending-the-patch


3. The "feature" is still documented:
https://www.tarantool.io/en/doc/latest/reference/reference_lua/net_box/#conn-timeout

You need to add a docbot request to the commit message for the
documentation team to remove all the mentionings of the old API.

For the syntax you can look at
https://github.com/tarantool/docbot#docbot---tarantool-documentation-pipeline-bot.

For examples: grep by `TarantoolBot` in git log.

> diff --git a/changelogs/unreleased/gh-6242-net-box-drop-conn-timeout.md b/changelogs/unreleased/gh-6242-net-box-drop-conn-timeout.md
> new file mode 100644
> index 000000000000..69d12fb858e5
> --- /dev/null
> +++ b/changelogs/unreleased/gh-6242-net-box-drop-conn-timeout.md
> @@ -0,0 +1,9 @@
> +## feature/core
> +
> +* **[Breaking change]** timeout() method of net.box connection, which was
> +  marked deprecated more than four years ago (in 1.7.4) was dropped, because
> +  it negatively affected performance of hot net.box methods, like call() and
> +  select(), in case those are called without specifying a timeout.

4. Wouldn't it be hard, please, to reference the issue in the end
of the text using `(gh-####)` format? See other changelogs for examples.

> +
> +---
> +Breaking change: timeout() method of net.box connection was dropped.
> diff --git a/src/box/lua/net_box.lua b/src/box/lua/net_box.lua
> index 3878abf21914..15e6c093cc15 100644
> --- a/src/box/lua/net_box.lua
> +++ b/src/box/lua/net_box.lua
> @@ -1289,28 +1280,11 @@ end
>  
>  function remote_methods:wait_state(state, timeout)
>      check_remote_arg(self, 'wait_state')
> -    if timeout == nil then
> -        local deadline = self._deadlines[fiber_self()]
> -        timeout = deadline and max(0, deadline - fiber_clock())
> -    end
>      return self._transport.wait_state(state, timeout)
>  end
>  
>  local compat_warning_said = false
>  
> --- @deprecated since 1.7.4
> -function remote_methods:timeout(timeout)
> -    check_remote_arg(self, 'timeout')
> -    if not compat_warning_said then

5. compat_warning_said can be deleted now.

In the future you can find such remnants using luacheck, which was
integrated into our CI and can be run locally. For that you need
to install Tarantool into any folder, install luacheck rock, and
then you can do something like this:

	$ ./.rocks/bin/luacheck --codes --config .luacheckrc src/box/lua/net_box.lua
	Checking src/box/lua/net_box.lua                  1 warning

   		 src/box/lua/net_box.lua:1286:7: (W211) unused variable compat_warning_said

Re: [Tarantool-patches] [PATCH] net.box: drop conn:timeout()

[Vladimir Davydov via Tarantool-patches]

On Tue, Jul 27, 2021 at 12:37:17AM +0200, Vladislav Shpilevoy wrote:
> See 5 comments below.

All fixed, thanks. The patch is below:

https://github.com/tarantool/tarantool/tree/vdavydov/net-box-drop-conn-timeout

From f1dbd33e4ccbc586d12460b9061c4c6a30b95f32 Mon Sep 17 00:00:00 2001
From: Vladimir Davydov <vdavydov@tarantool.org>
Date: Mon, 26 Jul 2021 11:59:15 +0300
Subject: [PATCH] net.box: drop conn:timeout()

conn:timeout(timeout) writes (now + timeout) to conn._deadlines table
keyed by fiber.self(). The deadline will then be used by all conn
methods unless specified explicitly in the options argument.

Usage of fiber.self() degrades net.box performance by about 15% in case
timeout is not specified, because it is a C call and so interferes with
JIT. See the ticket for the test details.

Since the feature is unusable and was deprecated more than four years
ago (in 1.7.4) in favor of specifying timeout in the options argument
(see commit 58da206c33197 ("net.box: add { timeout = } option to
requests")), it should be fine to drop it.

Closes #6242

@TarantoolBot document
Title: Delete documentation entry for net.box conn:timeout()

conn:timeout() was deprecated more than four years ago (in 1.7.4). Since
it results in performance degradation in case timeout is not specified
explicitly in request options, we decided to drop it. Please remove it
from the documentation as well:

https://www.tarantool.io/en/doc/latest/reference/reference_lua/net_box/#conn-timeout

diff --git a/changelogs/unreleased/gh-6242-net-box-drop-conn-timeout.md b/changelogs/unreleased/gh-6242-net-box-drop-conn-timeout.md
new file mode 100644
index 000000000000..9571c0afc577
--- /dev/null
+++ b/changelogs/unreleased/gh-6242-net-box-drop-conn-timeout.md
@@ -0,0 +1,9 @@
+## feature/core
+
+* **[Breaking change]** timeout() method of net.box connection, which was
+  marked deprecated more than four years ago (in 1.7.4) was dropped, because
+  it negatively affected performance of hot net.box methods, like call() and
+  select(), in case those are called without specifying a timeout (gh-6242).
+
+---
+Breaking change: timeout() method of net.box connection was dropped.
diff --git a/src/box/lua/net_box.lua b/src/box/lua/net_box.lua
index 3878abf21914..d70927989b71 100644
--- a/src/box/lua/net_box.lua
+++ b/src/box/lua/net_box.lua
@@ -1047,9 +1047,6 @@ local function new_sm(host, port, opts, connection, greeting)
         setmetatable(remote, console_mt)
     else
         setmetatable(remote, remote_mt)
-        -- @deprecated since 1.7.4
-        remote._deadlines = setmetatable({}, {__mode = 'k'})
-
         remote._space_mt = space_metatable(remote)
         remote._index_mt = index_metatable(remote)
         if opts.call_16 then
@@ -1176,17 +1173,11 @@ function remote_methods:_request(method, opts, request_ctx, ...)
             return res
         end
         if opts.timeout then
-            -- conn.space:request(, { timeout = timeout })
             deadline = fiber_clock() + opts.timeout
-        else
-            -- conn:timeout(timeout).space:request()
-            -- @deprecated since 1.7.4
-            deadline = self._deadlines[fiber_self()]
         end
         on_push = opts.on_push or on_push_sync_default
         on_push_ctx = opts.on_push_ctx
     else
-        deadline = self._deadlines[fiber_self()]
         on_push = on_push_sync_default
     end
     -- Execute synchronous request.
@@ -1289,28 +1280,9 @@ end
 
 function remote_methods:wait_state(state, timeout)
     check_remote_arg(self, 'wait_state')
-    if timeout == nil then
-        local deadline = self._deadlines[fiber_self()]
-        timeout = deadline and max(0, deadline - fiber_clock())
-    end
     return self._transport.wait_state(state, timeout)
 end
 
-local compat_warning_said = false
-
--- @deprecated since 1.7.4
-function remote_methods:timeout(timeout)
-    check_remote_arg(self, 'timeout')
-    if not compat_warning_said then
-        compat_warning_said = true
-        log.warn("netbox:timeout(timeout) is deprecated since 1.7.4, "..
-                 "please use space:<request>(..., {timeout = t}) instead.")
-    end
-    -- Sic: this is broken by design
-    self._deadlines[fiber_self()] = (timeout and fiber_clock() + timeout)
-    return self
-end
-
 function remote_methods:_install_schema(schema_version, spaces, indices,
                                         collations)
     local sl, space_mt, index_mt = {}, self._space_mt, self._index_mt
diff --git a/test/box/net.box_count_inconsistent_gh-3262.result b/test/box/net.box_count_inconsistent_gh-3262.result
index c77677625d97..286f9ded8aea 100644
--- a/test/box/net.box_count_inconsistent_gh-3262.result
+++ b/test/box/net.box_count_inconsistent_gh-3262.result
@@ -427,55 +427,6 @@ cn:eval('return ret_after(...)', {1.00}, { timeout = 1e-9 })
 ---
 - error: Timeout exceeded
 ...
---
--- :timeout()
--- @deprecated since 1.7.4
---
-cn:timeout(1).space.net_box_test_space.index.primary:select{234}
----
-- - [234, 1, 2, 3]
-...
-cn:call('ret_after', {.01})
----
-- [[0.01]]
-...
-cn:timeout(1):call('ret_after', {.01})
----
-- [[0.01]]
-...
-cn:timeout(.01):call('ret_after', {1})
----
-- error: Timeout exceeded
-...
-cn = remote:timeout(0.0000000001):connect(LISTEN.host, LISTEN.service, { user = 'netbox', password = '123' })
----
-...
-cn:close()
----
-...
-cn = remote:timeout(1):connect(LISTEN.host, LISTEN.service, { user = 'netbox', password = '123' })
----
-...
-remote.self:ping()
----
-- true
-...
-remote.self.space.net_box_test_space:select{234}
----
-- - [234, 1, 2, 3]
-...
-remote.self:timeout(123).space.net_box_test_space:select{234}
----
-- - [234, 1, 2, 3]
-...
-remote.self:is_connected()
----
-- true
-...
-remote.self:wait_connected()
----
-- true
-...
 cn:close()
 ---
 ...
diff --git a/test/box/net.box_count_inconsistent_gh-3262.test.lua b/test/box/net.box_count_inconsistent_gh-3262.test.lua
index e84e85cf3829..a6d87cdcc830 100644
--- a/test/box/net.box_count_inconsistent_gh-3262.test.lua
+++ b/test/box/net.box_count_inconsistent_gh-3262.test.lua
@@ -155,26 +155,6 @@ cn:call('ret_after', {1.00}, { timeout = 1e-9 })
 cn:eval('return ret_after(...)', {0.01}, { timeout = 1.00 })
 cn:eval('return ret_after(...)', {1.00}, { timeout = 1e-9 })
 
---
--- :timeout()
--- @deprecated since 1.7.4
---
-
-cn:timeout(1).space.net_box_test_space.index.primary:select{234}
-cn:call('ret_after', {.01})
-cn:timeout(1):call('ret_after', {.01})
-cn:timeout(.01):call('ret_after', {1})
-
-cn = remote:timeout(0.0000000001):connect(LISTEN.host, LISTEN.service, { user = 'netbox', password = '123' })
-cn:close()
-cn = remote:timeout(1):connect(LISTEN.host, LISTEN.service, { user = 'netbox', password = '123' })
-
-remote.self:ping()
-remote.self.space.net_box_test_space:select{234}
-remote.self:timeout(123).space.net_box_test_space:select{234}
-remote.self:is_connected()
-remote.self:wait_connected()
-
 cn:close()
 -- cleanup database after tests
 space:drop()

Re: [Tarantool-patches] [PATCH] net.box: drop conn:timeout()

[Vladislav Shpilevoy via Tarantool-patches]

Hi! Thanks for the fixes!

LGTM.

Re: [Tarantool-patches] [PATCH] net.box: drop conn:timeout()

[Vladimir Davydov via Tarantool-patches]

Pushed to master.