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deps: V8: cherry-pick b49206d fom upstream #20727
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Original commit message: ThreadDataTable: Change global linked list to per-Isolate hash map. For use cases with a large number of threads or a large number of isolates (or both), ThreadDataTable can be a major performance bottleneck due to O(n) lookup time of the linked list. Switching to a hash map reduces this to O(1). Example 1: Sandstorm.io, a Node.js app that utilizes "fibers", was observed spending the majority of CPU time iterating over the ThreadDataTable. See: https://sandstorm.io/news/2016-09-30-fiber-bomb-debugging-story Example 2: Cloudflare's Workers engine, a high-multi-tenancy web server framework built on V8 (but not Node), creates large numbers of threads and isolates per-process. It saw a 34x improvement in throughput when we applied this patch. Cloudflare has been using a patch in production since the Workers launch which replaces the linked list with a hash map -- but still global. This commit builds on that but goes further and creates a separate hash map and mutex for each isolate, with the table being a member of the Isolate class. This avoids any globals and should reduce lock contention. Bug: v8:5338 Change-Id: If0d11509afb2e043b888c376e36d3463db931b47 Reviewed-on: https://chromium-review.googlesource.com/1014407 Reviewed-by: Yang Guo <[email protected]> Commit-Queue: Yang Guo <[email protected]> Cr-Commit-Position: refs/heads/master@{nodejs#52753} PR-URL: nodejs#20727 Ref: nodejs#20083
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LGTM. New CI because the previous one bombed on infrastructure issues:
New CI was all green: https://ci.nodejs.org/job/node-test-commit/18544/. Landing. |
Landed in 0ebbd76. |
Original commit message: ThreadDataTable: Change global linked list to per-Isolate hash map. For use cases with a large number of threads or a large number of isolates (or both), ThreadDataTable can be a major performance bottleneck due to O(n) lookup time of the linked list. Switching to a hash map reduces this to O(1). Example 1: Sandstorm.io, a Node.js app that utilizes "fibers", was observed spending the majority of CPU time iterating over the ThreadDataTable. See: https://sandstorm.io/news/2016-09-30-fiber-bomb-debugging-story Example 2: Cloudflare's Workers engine, a high-multi-tenancy web server framework built on V8 (but not Node), creates large numbers of threads and isolates per-process. It saw a 34x improvement in throughput when we applied this patch. Cloudflare has been using a patch in production since the Worker launch which replaces the linked list with a hash map -- but still global. This commit builds on that but goes further and creates a separate hash map and mutex for each isolate, with the table being a member of the Isolate class. This avoids any globals and should reduce lock contention. Bug: v8:5338 Change-Id: If0d11509afb2e043b888c376e36d3463db931b47 Reviewed-on: https://chromium-review.googlesource.com/1014407 Reviewed-by: Yang Guo <[email protected]> Commit-Queue: Yang Guo <[email protected]> Cr-Commit-Position: refs/heads/master@{#52753} PR-URL: #20727 Ref: #20083 Refs: #20083 Reviewed-By: Ben Noordhuis <[email protected]> Reviewed-By: James M Snell <[email protected]>
@ofrobots is there anything still needed to get this into Node.js 8? |
@KoenLav the process we follow is that a fix first has to be available on the current release line before it is considered for back-porting to LTS by the @nodejs/release team. I have attached the labels above which will make this fix show up on the list of potential back-ports to the LTS releases. It is going to take a little while before you see it on 8 LTS – but the objective is to make sure we have adequate feedback from the current line to avoid disrupting the LTS lines.. /cc @nodejs/release in case I got anything wrong about the release process. |
Original commit message: ThreadDataTable: Change global linked list to per-Isolate hash map. For use cases with a large number of threads or a large number of isolates (or both), ThreadDataTable can be a major performance bottleneck due to O(n) lookup time of the linked list. Switching to a hash map reduces this to O(1). Example 1: Sandstorm.io, a Node.js app that utilizes "fibers", was observed spending the majority of CPU time iterating over the ThreadDataTable. See: https://sandstorm.io/news/2016-09-30-fiber-bomb-debugging-story Example 2: Cloudflare's Workers engine, a high-multi-tenancy web server framework built on V8 (but not Node), creates large numbers of threads and isolates per-process. It saw a 34x improvement in throughput when we applied this patch. Cloudflare has been using a patch in production since the Worker launch which replaces the linked list with a hash map -- but still global. This commit builds on that but goes further and creates a separate hash map and mutex for each isolate, with the table being a member of the Isolate class. This avoids any globals and should reduce lock contention. Bug: v8:5338 Change-Id: If0d11509afb2e043b888c376e36d3463db931b47 Reviewed-on: https://chromium-review.googlesource.com/1014407 Reviewed-by: Yang Guo <[email protected]> Commit-Queue: Yang Guo <[email protected]> Cr-Commit-Position: refs/heads/master@{#52753} PR-URL: #20727 Ref: #20083 Refs: #20083 Reviewed-By: Ben Noordhuis <[email protected]> Reviewed-By: James M Snell <[email protected]>
@ofrobots Any idea on when this might land in Node 8? It'll be a huge deal for the Meteor community :) |
@MylesBorins is this on track for a |
@ofrobots this is going to need a manual backport to 8.x ping @nodejs/v8-update |
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This is the v8.x backport of nodejs#20727. Original commit message: ThreadDataTable: Change global linked list to per-Isolate hash map. For use cases with a large number of threads or a large number of isolates (or both), ThreadDataTable can be a major performance bottleneck due to O(n) lookup time of the linked list. Switching to a hash map reduces this to O(1). Example 1: Sandstorm.io, a Node.js app that utilizes "fibers", was observed spending the majority of CPU time iterating over the ThreadDataTable. See: https://sandstorm.io/news/2016-09-30-fiber-bomb-debugging-story Example 2: Cloudflare's Workers engine, a high-multi-tenancy web server framework built on V8 (but not Node), creates large numbers of threads and isolates per-process. It saw a 34x improvement in throughput when we applied this patch. Cloudflare has been using a patch in production since the Worker launch which replaces the linked list with a hash map -- but still global. This commit builds on that but goes further and creates a separate hash map and mutex for each isolate, with the table being a member of the Isolate class. This avoids any globals and should reduce lock contention. Bug: v8:5338 Change-Id: If0d11509afb2e043b888c376e36d3463db931b47 Reviewed-on: https://chromium-review.googlesource.com/1014407 Reviewed-by: Yang Guo <[email protected]> Commit-Queue: Yang Guo <[email protected]> Cr-Commit-Position: refs/heads/master@{nodejs#52753} Backport-PR-URL: nodejs#21529 PR-URL: nodejs#20727 Refs: nodejs#20083 Refs: nodejs#20083 Reviewed-By: Ben Noordhuis <[email protected]> Reviewed-By: James M Snell <[email protected]>
This is the v8.x backport of #20727. Original commit message: ThreadDataTable: Change global linked list to per-Isolate hash map. For use cases with a large number of threads or a large number of isolates (or both), ThreadDataTable can be a major performance bottleneck due to O(n) lookup time of the linked list. Switching to a hash map reduces this to O(1). Example 1: Sandstorm.io, a Node.js app that utilizes "fibers", was observed spending the majority of CPU time iterating over the ThreadDataTable. See: https://sandstorm.io/news/2016-09-30-fiber-bomb-debugging-story Example 2: Cloudflare's Workers engine, a high-multi-tenancy web server framework built on V8 (but not Node), creates large numbers of threads and isolates per-process. It saw a 34x improvement in throughput when we applied this patch. Cloudflare has been using a patch in production since the Worker launch which replaces the linked list with a hash map -- but still global. This commit builds on that but goes further and creates a separate hash map and mutex for each isolate, with the table being a member of the Isolate class. This avoids any globals and should reduce lock contention. Bug: v8:5338 Change-Id: If0d11509afb2e043b888c376e36d3463db931b47 Reviewed-on: https://chromium-review.googlesource.com/1014407 Reviewed-by: Yang Guo <[email protected]> Commit-Queue: Yang Guo <[email protected]> Cr-Commit-Position: refs/heads/master@{#52753} Backport-PR-URL: #21529 PR-URL: #20727 Refs: #20083 Refs: #20083 Reviewed-By: Ben Noordhuis <[email protected]> Reviewed-By: James M Snell <[email protected]>
Ref: #20083
Original commit message:
Checklist
make -j4 test
(UNIX), orvcbuild test
(Windows) passesCI: https://ci.nodejs.org/job/node-test-pull-request/14871/
V8-CI: https://ci.nodejs.org/view/All/job/node-test-commit-v8-linux/1368/