From 22eb1e44362fd0aa5be0e1adbf1081dbd4919a10 Mon Sep 17 00:00:00 2001 From: Mircea Trofin Date: Wed, 21 Oct 2015 09:27:40 -0700 Subject: Separate scenarios motivating feature testing Moved a few of the already described scenarios, trying to isolate the motivating problem from possible solutions. Added a development time scenario and one for restrictive target environment. --- FeatureTest.md | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'FeatureTest.md') diff --git a/FeatureTest.md b/FeatureTest.md index 0010b1e..f00a682 100644 --- a/FeatureTest.md +++ b/FeatureTest.md @@ -1,3 +1,18 @@ +# Motivating Scenarios +1. In MVP + 1 (the version of the WebAssembly after MVP), [`i32.min_s`](FutureFeatures.md#additional-integer-operations) is introduced. A developer updates her toolkit and targets the new features. The compiler leverages `i32.min_s` when compiling a module the developer wrote. The developer's WebAssembly module works correctly both on execution environments at MVP, as well as those updated on MVP + 1. + +2. In MVP + 1, module authors may now use [Threading](PostMVP.md#threads) APIs in the browser. A developer wants to leverage multithreading in her module. + * In one variant of the scenario, the developer does not want to pay the engineering cost of developing and supporting a threaded and non-threaded version of her code. She opts to not support MVP targets, and only support MVP + 1 targets. End-users (browser users) get some message indicating they need MVP support. + * In another variant, the developer explicitly authors both MVP-only and MVP + 1 (with threads) code. + +3. [SIMD](PostMVP.md#fixed-width-simd) support is not universally equivalent on all targets. While polyfill variants of SIMD APIs are available, a developer prefers writing dedicated SIMD and non-SIMD versions of her compresion algorithm, because the non-SIMD version performs better in environments without SIMD support, when compared to the SIMD polyfill. She packages her compression code for reuse by third parties. + +4. A developer is assembling together an application reusing modules developed in the scenarios above. Their development environment is able to quickly and correctly identify the platform dependencies (e.g. threading, SIMD) and communicate to the developer the implications these dependencies have on the end-application. Some APIs exposed from the threading-aware module are only pertinent to environments supporting threading. As a consequence, our developer needs to write specialized code when threads are/are not supported. +(Note: we should understand ghis scenario for both forms of WebAssembly reuse currently imagined - dynamic linking and static imports.) + +5. A module (for example the compression one), or the application described in the scenarios above, is deployed on a restrictive execution environment where a process may not change memory page access protection flags (certain gaming consoles, to investigate server side deployment scenarios). The module is compiled by the WebAssembly environment, enabling the configuration most specific to the target (i.e. with/without Threads, SIMD, etc). + * A variant of this scenario where the environment is additionally separating storage into system-visible and application-visible, the latter not being able to contain machine-executable code (certain phones, to investigate if gaming consoles or server side have a similar sandboxing mechanism). + # Feature Test The [MVP](MVP.md) allows an application to query which post-MVP features are -- cgit v1.2.3 From 7347fc654d230a4887bf24db194ce57bab04b286 Mon Sep 17 00:00:00 2001 From: Mircea Trofin Date: Wed, 21 Oct 2015 19:51:51 -0700 Subject: Incorporated feedback. - link to PostMVP.md - replaced pronouns with giving the user a name in each scenario, and then using the appropriate pronoun. This makes cross-referencing scenarios easier, too. --- FeatureTest.md | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'FeatureTest.md') diff --git a/FeatureTest.md b/FeatureTest.md index f00a682..b826380 100644 --- a/FeatureTest.md +++ b/FeatureTest.md @@ -1,16 +1,16 @@ # Motivating Scenarios -1. In MVP + 1 (the version of the WebAssembly after MVP), [`i32.min_s`](FutureFeatures.md#additional-integer-operations) is introduced. A developer updates her toolkit and targets the new features. The compiler leverages `i32.min_s` when compiling a module the developer wrote. The developer's WebAssembly module works correctly both on execution environments at MVP, as well as those updated on MVP + 1. +1. In MVP + 1 (the version of the WebAssembly [after MVP](PostMVP.md)), [`i32.min_s`](FutureFeatures.md#additional-integer-operations) is introduced. Mary, a WebAssembly developer, updates her toolkit and targets the new features. The compiler leverages `i32.min_s` when compiling a module the developer wrote. Mary's WebAssembly module works correctly both on execution environments at MVP, as well as those updated on MVP + 1. -2. In MVP + 1, module authors may now use [Threading](PostMVP.md#threads) APIs in the browser. A developer wants to leverage multithreading in her module. - * In one variant of the scenario, the developer does not want to pay the engineering cost of developing and supporting a threaded and non-threaded version of her code. She opts to not support MVP targets, and only support MVP + 1 targets. End-users (browser users) get some message indicating they need MVP support. - * In another variant, the developer explicitly authors both MVP-only and MVP + 1 (with threads) code. +2. In MVP + 1, module authors may now use [Threading](PostMVP.md#threads) APIs in the browser. Bob is such a developer, and he wants to leverage multithreading in his module. + * In one variant of the scenario, Bob does not want to pay the engineering cost of developing and supporting a threaded and non-threaded version of her code. He opts to not support MVP targets, and only support MVP + 1 targets. End-users (browser users) get some message indicating they need MVP support. + * In another variant, Bob explicitly authors both MVP-only and MVP + 1 (with threads) code. -3. [SIMD](PostMVP.md#fixed-width-simd) support is not universally equivalent on all targets. While polyfill variants of SIMD APIs are available, a developer prefers writing dedicated SIMD and non-SIMD versions of her compresion algorithm, because the non-SIMD version performs better in environments without SIMD support, when compared to the SIMD polyfill. She packages her compression code for reuse by third parties. +3. [SIMD](PostMVP.md#fixed-width-simd) support is not universally equivalent on all targets. While polyfill variants of SIMD APIs are available, Jane prefers writing dedicated SIMD and non-SIMD versions of her compresion algorithm, because the non-SIMD version performs better in environments without SIMD support, when compared to the SIMD polyfill. She packages her compression code for reuse by third parties. -4. A developer is assembling together an application reusing modules developed in the scenarios above. Their development environment is able to quickly and correctly identify the platform dependencies (e.g. threading, SIMD) and communicate to the developer the implications these dependencies have on the end-application. Some APIs exposed from the threading-aware module are only pertinent to environments supporting threading. As a consequence, our developer needs to write specialized code when threads are/are not supported. +4. Chris is assembling together an application reusing modules developed in the scenarios above. His development environment is able to quickly and correctly identify the platform dependencies (e.g. threading, SIMD) and communicate back to him the implications these dependencies have on the end-application. Some APIs exposed from the threading-aware module are only pertinent to environments supporting threading. As a consequence, Chris needs to write specialized code when threads are/are not supported. (Note: we should understand ghis scenario for both forms of WebAssembly reuse currently imagined - dynamic linking and static imports.) -5. A module (for example the compression one), or the application described in the scenarios above, is deployed on a restrictive execution environment where a process may not change memory page access protection flags (certain gaming consoles, to investigate server side deployment scenarios). The module is compiled by the WebAssembly environment, enabling the configuration most specific to the target (i.e. with/without Threads, SIMD, etc). +5. Jane's compression algorithm module is deployed on a restrictive execution environment, as part of an application. In this environment, a process may not change memory page access protection flags (e.g. certain gaming consoles, to investigate server side deployment scenarios). Jane's module is compiled by the WebAssembly environment, enabling the configuration most specific to the target (i.e. with/without Threads, SIMD, etc). * A variant of this scenario where the environment is additionally separating storage into system-visible and application-visible, the latter not being able to contain machine-executable code (certain phones, to investigate if gaming consoles or server side have a similar sandboxing mechanism). # Feature Test -- cgit v1.2.3 From 4d692a0f06f70b0a425339a4799599097ac67d3f Mon Sep 17 00:00:00 2001 From: Mircea Trofin Date: Thu, 22 Oct 2015 22:48:42 -0700 Subject: Back to pronouns. --- FeatureTest.md | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'FeatureTest.md') diff --git a/FeatureTest.md b/FeatureTest.md index b826380..53d099f 100644 --- a/FeatureTest.md +++ b/FeatureTest.md @@ -1,13 +1,13 @@ # Motivating Scenarios -1. In MVP + 1 (the version of the WebAssembly [after MVP](PostMVP.md)), [`i32.min_s`](FutureFeatures.md#additional-integer-operations) is introduced. Mary, a WebAssembly developer, updates her toolkit and targets the new features. The compiler leverages `i32.min_s` when compiling a module the developer wrote. Mary's WebAssembly module works correctly both on execution environments at MVP, as well as those updated on MVP + 1. +1. In MVP + 1 (the version of the WebAssembly [after MVP](PostMVP.md)), [`i32.min_s`](FutureFeatures.md#additional-integer-operations) is introduced. A WebAssembly developer updates their toolkit and targets the new features. The compiler leverages `i32.min_s` when compiling a module the developer wrote. The developer's WebAssembly module works correctly both on execution environments at MVP, as well as those updated on MVP + 1. -2. In MVP + 1, module authors may now use [Threading](PostMVP.md#threads) APIs in the browser. Bob is such a developer, and he wants to leverage multithreading in his module. - * In one variant of the scenario, Bob does not want to pay the engineering cost of developing and supporting a threaded and non-threaded version of her code. He opts to not support MVP targets, and only support MVP + 1 targets. End-users (browser users) get some message indicating they need MVP support. - * In another variant, Bob explicitly authors both MVP-only and MVP + 1 (with threads) code. +2. In MVP + 1, module authors may now use [Threading](PostMVP.md#threads) APIs in the browser. A developer wants to leverage multithreading in their module. + * In one variant of the scenario, our developer does not want to pay the engineering cost of developing and supporting a threaded and non-threaded version of their code. They opt not to support MVP targets, and only support MVP + 1 targets. End-users (browser users) get some message indicating they need MVP support. + * In another variant, our developer explicitly authors both MVP-only and MVP + 1 (with threads) code. -3. [SIMD](PostMVP.md#fixed-width-simd) support is not universally equivalent on all targets. While polyfill variants of SIMD APIs are available, Jane prefers writing dedicated SIMD and non-SIMD versions of her compresion algorithm, because the non-SIMD version performs better in environments without SIMD support, when compared to the SIMD polyfill. She packages her compression code for reuse by third parties. +3. [SIMD](PostMVP.md#fixed-width-simd) support is not universally equivalent on all targets. While polyfill variants of SIMD APIs are available, a developer prefers writing dedicated SIMD and non-SIMD versions of their compresion algorithm, because the non-SIMD version performs better in environments without SIMD support, when compared to the SIMD polyfill. They package their compression code for reuse by third parties. -4. Chris is assembling together an application reusing modules developed in the scenarios above. His development environment is able to quickly and correctly identify the platform dependencies (e.g. threading, SIMD) and communicate back to him the implications these dependencies have on the end-application. Some APIs exposed from the threading-aware module are only pertinent to environments supporting threading. As a consequence, Chris needs to write specialized code when threads are/are not supported. +4. An application author is assembling together an application by reusing modules such as those developed in the scenarios above. The application author's development environment is able to quickly and correctly identify the platform dependencies (e.g. threading, SIMD) and communicate back to the application author the implications these dependencies have on the end-application. Some APIs exposed from the threading-aware module are only pertinent to environments supporting threading. As a consequence, the application author needs to write specialized code when threads are/are not supported. (Note: we should understand ghis scenario for both forms of WebAssembly reuse currently imagined - dynamic linking and static imports.) 5. Jane's compression algorithm module is deployed on a restrictive execution environment, as part of an application. In this environment, a process may not change memory page access protection flags (e.g. certain gaming consoles, to investigate server side deployment scenarios). Jane's module is compiled by the WebAssembly environment, enabling the configuration most specific to the target (i.e. with/without Threads, SIMD, etc). -- cgit v1.2.3 From 631a2c0befed980923d81ca7051343b3653f0de9 Mon Sep 17 00:00:00 2001 From: Mircea Trofin Date: Mon, 26 Oct 2015 18:28:44 -0700 Subject: Update FeatureTest.md --- FeatureTest.md | 15 +-------------- 1 file changed, 1 insertion(+), 14 deletions(-) (limited to 'FeatureTest.md') diff --git a/FeatureTest.md b/FeatureTest.md index 53d099f..5470b72 100644 --- a/FeatureTest.md +++ b/FeatureTest.md @@ -1,17 +1,4 @@ -# Motivating Scenarios -1. In MVP + 1 (the version of the WebAssembly [after MVP](PostMVP.md)), [`i32.min_s`](FutureFeatures.md#additional-integer-operations) is introduced. A WebAssembly developer updates their toolkit and targets the new features. The compiler leverages `i32.min_s` when compiling a module the developer wrote. The developer's WebAssembly module works correctly both on execution environments at MVP, as well as those updated on MVP + 1. - -2. In MVP + 1, module authors may now use [Threading](PostMVP.md#threads) APIs in the browser. A developer wants to leverage multithreading in their module. - * In one variant of the scenario, our developer does not want to pay the engineering cost of developing and supporting a threaded and non-threaded version of their code. They opt not to support MVP targets, and only support MVP + 1 targets. End-users (browser users) get some message indicating they need MVP support. - * In another variant, our developer explicitly authors both MVP-only and MVP + 1 (with threads) code. - -3. [SIMD](PostMVP.md#fixed-width-simd) support is not universally equivalent on all targets. While polyfill variants of SIMD APIs are available, a developer prefers writing dedicated SIMD and non-SIMD versions of their compresion algorithm, because the non-SIMD version performs better in environments without SIMD support, when compared to the SIMD polyfill. They package their compression code for reuse by third parties. - -4. An application author is assembling together an application by reusing modules such as those developed in the scenarios above. The application author's development environment is able to quickly and correctly identify the platform dependencies (e.g. threading, SIMD) and communicate back to the application author the implications these dependencies have on the end-application. Some APIs exposed from the threading-aware module are only pertinent to environments supporting threading. As a consequence, the application author needs to write specialized code when threads are/are not supported. -(Note: we should understand ghis scenario for both forms of WebAssembly reuse currently imagined - dynamic linking and static imports.) - -5. Jane's compression algorithm module is deployed on a restrictive execution environment, as part of an application. In this environment, a process may not change memory page access protection flags (e.g. certain gaming consoles, to investigate server side deployment scenarios). Jane's module is compiled by the WebAssembly environment, enabling the configuration most specific to the target (i.e. with/without Threads, SIMD, etc). - * A variant of this scenario where the environment is additionally separating storage into system-visible and application-visible, the latter not being able to contain machine-executable code (certain phones, to investigate if gaming consoles or server side have a similar sandboxing mechanism). +See [rationale](Rationale.md#feature-testing---motivating-scenarios) for motivating scenarios. # Feature Test -- cgit v1.2.3