Stream: rfc-notifications

Topic: rfcs / Issue #10 RFC: Transition Cranelift and Wasmtime t...

RFC notifications bot (Mar 18 2021 at 00:07):

cfallin commented on Issue #10:

I spent some time today running Sightglass and looking at the results. The following numbers are from 184a039 in my new-backend branch vs. current main, which is 5fecdfa. All time measurements are on Linux/x86-64 on a Ryzen 3900X @ 3.8GHz, with 3 iterations, arithmetic mean for times and geometric mean across speedups:

Compilation time

|--------------------|--------------------|--------------------|--------|
|       blake3-scalar|       68972585.0 ns|      146270137.0 ns|  0.472x|
|         blake3-simd|       17564151.7 ns|       32353641.7 ns|  0.543x|
|                noop|        9321450.7 ns|       17151835.7 ns|  0.543x|
|      pulldown-cmark|      144998015.3 ns|      300286274.7 ns|  0.483x|
|  shootout-ackermann|       42469345.0 ns|       49661814.3 ns|  0.855x|
|     shootout-base64|       41245124.3 ns|       44928123.3 ns|  0.918x|
|      shootout-ctype|       39737061.7 ns|       43569184.7 ns|  0.912x|
|    shootout-ed25519|       60436223.0 ns|      179996537.0 ns|  0.336x|
|       shootout-fib2|       39346114.7 ns|       40560157.7 ns|  0.970x|
|      shootout-gimli|        3267325.7 ns|        5164884.3 ns|  0.633x|
|   shootout-heapsort|       10727494.3 ns|       16877485.3 ns|  0.636x|
|     shootout-keccak|       11902052.0 ns|       23934554.3 ns|  0.497x|
|     shootout-matrix|       41642608.7 ns|       43212095.3 ns|  0.964x|
|    shootout-memmove|       10944073.7 ns|       15006035.0 ns|  0.729x|
|    shootout-minicsv|        5230805.0 ns|        8374252.0 ns|  0.625x|
| shootout-nestedloop|       39301089.0 ns|       41444058.7 ns|  0.948x|
|     shootout-random|       37677048.0 ns|       39413521.7 ns|  0.956x|
|  shootout-ratelimit|       42176894.7 ns|       42664704.3 ns|  0.989x|
|    shootout-seqhash|       10257756.3 ns|       13729952.7 ns|  0.747x|
|      shootout-sieve|       38677786.7 ns|       41630312.3 ns|  0.929x|
|     shootout-switch|     1246419944.3 ns|       45154181.7 ns| 27.604x|
|  shootout-xblabla20|       10846952.7 ns|       15154782.7 ns|  0.716x|
|  shootout-xchacha20|       10538490.7 ns|       13492446.7 ns|  0.781x|
|--------------------|--------------------|--------------------|--------|
Geomean: 0.828489

Execution time

|--------------------|--------------------|--------------------|--------|
|       blake3-scalar|         124991.7 ns|         161477.0 ns|  0.774x|
|         blake3-simd|         191938.3 ns|         268173.7 ns|  0.716x|
|                noop|             92.3 ns|             69.0 ns|  1.338x|
|      pulldown-cmark|        2915551.0 ns|        2601125.3 ns|  1.121x|
|  shootout-ackermann|            125.7 ns|            142.3 ns|  0.883x|
|     shootout-base64|      120473405.7 ns|      118650169.7 ns|  1.015x|
|      shootout-ctype|      327814007.0 ns|      288553357.7 ns|  1.136x|
|    shootout-ed25519|     3285211842.3 ns|     3355830768.3 ns|  0.979x|
|       shootout-fib2|     1288032348.7 ns|     1121754822.3 ns|  1.148x|
|      shootout-gimli|        3953612.7 ns|        3842533.3 ns|  1.029x|
|   shootout-heapsort|      941783516.7 ns|      905448764.0 ns|  1.040x|
|     shootout-keccak|       11200864.7 ns|       11193635.0 ns|  1.001x|
|     shootout-matrix|      138431299.7 ns|       94843781.7 ns|  1.460x|
|    shootout-memmove|      478948004.0 ns|      312724823.7 ns|  1.532x|
|    shootout-minicsv|      719886639.3 ns|      553181699.7 ns|  1.301x|
| shootout-nestedloop|        9017709.0 ns|        7310325.0 ns|  1.234x|
|     shootout-random|      141097573.0 ns|      141046267.3 ns|  1.000x|
|  shootout-ratelimit|       15340715.7 ns|       14238039.7 ns|  1.077x|
|    shootout-seqhash|     3305572758.3 ns|     3652199454.7 ns|  0.905x|
|      shootout-sieve|      339462468.7 ns|      432978618.7 ns|  0.784x|
|     shootout-switch|       45572014.0 ns|       36769437.7 ns|  1.239x|
|  shootout-xblabla20|        1620894.0 ns|        2381350.3 ns|  0.681x|
|  shootout-xchacha20|        3260006.0 ns|        2719482.7 ns|  1.199x|
|--------------------|--------------------|--------------------|--------|
Geomean: 1.046229

Thoughts

This is somewhat surprising to me; earlier measurements showed different results. For example, on Lucet's benchmarks when I last measured: on Dec 1, I recorded a 20% geomean perf improvement on that suite. I've generally measured compile time to improve relative to the old backend, e.g. about 1.5-2x last summer, though I haven't done a measurement recently.

So, something seems to have regressed; all the more motivation for continuous benchmarking. I haven't tried to bisect the shift.

That said, we still see a modest gain in execution speed on most benchmarks -- geomean of 4.6% better. A compilation time of 18% slower is a little more worrying -- a quick look with perf shows a bunch of time spent in regalloc.rs. I'm currently looking at options for regalloc improvements and am hoping to have something in the next few weeks.

I would propose that we still move forward with the transition, but this increases the urgency with which I'm working on this!

RFC notifications bot (Mar 25 2021 at 19:15):

cfallin commented on Issue #10:

Motion to finalize with a disposition to merge

So there is not much discussion here, but there also seem to be few objections. Given that runtime perf is generally positive, compatibility check-boxes are complete, and the maintenance story improves greatly once this moves forward, I'm proposing that we merge this RFC.

Stakeholders sign-off

Tagging all employees of BA-affiliated companies who have committed to the Wasmtime or Lucet repos in the last three months, plus anyone who has given feedback on this PR as a stakeholder.

Fastly

• [ ] @alexcrichton
• [x] @cfallin
• [ ] @sunfishcode
• [ ] @jedisct1
• [ ] @fitzgen
• [ ] @pchickey
• [ ] @peterhuene
• [ ] @acfoltzer
• [ ] @iximeow

Intel

• [ ] @abrown
• [ ] @jlb6740

IBM

• [ ] @uweigand

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• [ ] @julian-seward1
• [ ] @yurydelendik

Other Stakeholders

• [ ] @bnjbvr

RFC notifications bot (Mar 25 2021 at 19:16):

sunfishcode edited a comment on Issue #10:

Motion to finalize with a disposition to merge

So there is not much discussion here, but there also seem to be few objections. Given that runtime perf is generally positive, compatibility check-boxes are complete, and the maintenance story improves greatly once this moves forward, I'm proposing that we merge this RFC.

Stakeholders sign-off

Tagging all employees of BA-affiliated companies who have committed to the Wasmtime or Lucet repos in the last three months, plus anyone who has given feedback on this PR as a stakeholder.

Fastly

• [ ] @alexcrichton
• [x] @cfallin
• [x] @sunfishcode
• [ ] @jedisct1
• [ ] @fitzgen
• [ ] @pchickey
• [ ] @peterhuene
• [ ] @acfoltzer
• [ ] @iximeow

Intel

• [ ] @abrown
• [ ] @jlb6740

IBM

• [ ] @uweigand

Mozilla

• [ ] @julian-seward1
• [ ] @yurydelendik

Other Stakeholders

• [ ] @bnjbvr

RFC notifications bot (Mar 25 2021 at 19:24):

fitzgen edited a comment on Issue #10:

Motion to finalize with a disposition to merge

So there is not much discussion here, but there also seem to be few objections. Given that runtime perf is generally positive, compatibility check-boxes are complete, and the maintenance story improves greatly once this moves forward, I'm proposing that we merge this RFC.

Stakeholders sign-off

Tagging all employees of BA-affiliated companies who have committed to the Wasmtime or Lucet repos in the last three months, plus anyone who has given feedback on this PR as a stakeholder.

Fastly

• [ ] @alexcrichton
• [x] @cfallin
• [x] @sunfishcode
• [ ] @jedisct1
• [x] @fitzgen
• [ ] @pchickey
• [ ] @peterhuene
• [ ] @acfoltzer
• [ ] @iximeow

Intel

• [ ] @abrown
• [ ] @jlb6740

IBM

• [ ] @uweigand

Mozilla

• [ ] @julian-seward1
• [ ] @yurydelendik

Other Stakeholders

• [ ] @bnjbvr

RFC notifications bot (Mar 25 2021 at 19:25):

alexcrichton edited a comment on Issue #10:

Motion to finalize with a disposition to merge

So there is not much discussion here, but there also seem to be few objections. Given that runtime perf is generally positive, compatibility check-boxes are complete, and the maintenance story improves greatly once this moves forward, I'm proposing that we merge this RFC.

Stakeholders sign-off

Tagging all employees of BA-affiliated companies who have committed to the Wasmtime or Lucet repos in the last three months, plus anyone who has given feedback on this PR as a stakeholder.

Fastly

• [x] @alexcrichton
• [x] @cfallin
• [x] @sunfishcode
• [ ] @jedisct1
• [x] @fitzgen
• [ ] @pchickey
• [ ] @peterhuene
• [ ] @acfoltzer
• [ ] @iximeow

Intel

• [ ] @abrown
• [ ] @jlb6740

IBM

• [ ] @uweigand

Mozilla

• [ ] @julian-seward1
• [ ] @yurydelendik

Other Stakeholders

• [ ] @bnjbvr

RFC notifications bot (Mar 25 2021 at 19:52):

cfallin edited a comment on Issue #10:

Motion to finalize with a disposition to merge

So there is not much discussion here, but there also seem to be few objections. Given that runtime perf is generally positive, compatibility check-boxes are complete, and the maintenance story improves greatly once this moves forward, I'm proposing that we merge this RFC.

Stakeholders sign-off

Tagging all employees of BA-affiliated companies who have committed to the Wasmtime or Lucet repos in the last three months, plus anyone who has given feedback on this PR as a stakeholder.

Fastly

• [x] @alexcrichton
• [x] @cfallin
• [x] @sunfishcode
• [x] @jedisct1
• [x] @fitzgen
• [ ] @pchickey
• [ ] @peterhuene
• [ ] @acfoltzer
• [ ] @iximeow

Intel

• [ ] @abrown
• [ ] @jlb6740

IBM

• [ ] @uweigand

Mozilla

• [ ] @julian-seward1
• [ ] @yurydelendik

Other Stakeholders

• [ ] @bnjbvr

RFC notifications bot (Mar 25 2021 at 21:08):

cfallin edited a comment on Issue #10:

Motion to finalize with a disposition to merge

So there is not much discussion here, but there also seem to be few objections. Given that runtime perf is generally positive, compatibility check-boxes are complete, and the maintenance story improves greatly once this moves forward, I'm proposing that we merge this RFC.

Stakeholders sign-off

Tagging all employees of BA-affiliated companies who have committed to the Wasmtime or Lucet repos in the last three months, plus anyone who has given feedback on this PR as a stakeholder.

Fastly

• [x] @alexcrichton
• [x] @cfallin
• [x] @sunfishcode
• [x] @jedisct1
• [x] @fitzgen
• [x] @pchickey
• [ ] @peterhuene
• [ ] @acfoltzer
• [ ] @iximeow

Intel

• [ ] @abrown
• [ ] @jlb6740

IBM

• [ ] @uweigand

Mozilla

• [ ] @julian-seward1
• [ ] @yurydelendik

Other Stakeholders

• [ ] @bnjbvr

RFC notifications bot (Mar 26 2021 at 02:15):

jlb6740 commented on Issue #10:

I think the RFC looks great. Considering no alarms of missing features so far from those who have made the switch, 5 can be done after the switch before the removal of the legacy backend.

RFC notifications bot (Mar 26 2021 at 02:41):

cfallin edited a comment on Issue #10:

Motion to finalize with a disposition to merge

So there is not much discussion here, but there also seem to be few objections. Given that runtime perf is generally positive, compatibility check-boxes are complete, and the maintenance story improves greatly once this moves forward, I'm proposing that we merge this RFC.

Stakeholders sign-off

Tagging all employees of BA-affiliated companies who have committed to the Wasmtime or Lucet repos in the last three months, plus anyone who has given feedback on this PR as a stakeholder.

Fastly

• [x] @alexcrichton
• [x] @cfallin
• [x] @sunfishcode
• [x] @jedisct1
• [x] @fitzgen
• [x] @pchickey
• [ ] @peterhuene
• [ ] @acfoltzer
• [ ] @iximeow

Intel

• [x] @abrown
• [x] @jlb6740

IBM

• [ ] @uweigand

Mozilla

• [ ] @julian-seward1
• [ ] @yurydelendik

Other Stakeholders

• [ ] @bnjbvr

RFC notifications bot (Mar 26 2021 at 02:42):

cfallin commented on Issue #10:

Entering Final Call Period

https://github.com/bytecodealliance/rfcs/blob/main/accepted/rfc-process.md#making-a-decision-merge-or-close

Once any stakeholder from a different group has signed off, the RFC will move into a 10 calendar day final comment period (FCP), long enough to ensure that other stakeholders have at least a full business week to respond.

The FCP will end on Mon Apr 5.

RFC notifications bot (Mar 26 2021 at 08:20):

bnjbvr edited a comment on Issue #10:

Motion to finalize with a disposition to merge

So there is not much discussion here, but there also seem to be few objections. Given that runtime perf is generally positive, compatibility check-boxes are complete, and the maintenance story improves greatly once this moves forward, I'm proposing that we merge this RFC.

Stakeholders sign-off

Tagging all employees of BA-affiliated companies who have committed to the Wasmtime or Lucet repos in the last three months, plus anyone who has given feedback on this PR as a stakeholder.

Fastly

• [x] @alexcrichton
• [x] @cfallin
• [x] @sunfishcode
• [x] @jedisct1
• [x] @fitzgen
• [x] @pchickey
• [ ] @peterhuene
• [ ] @acfoltzer
• [ ] @iximeow

Intel

• [x] @abrown
• [x] @jlb6740

IBM

• [ ] @uweigand

Mozilla

• [ ] @julian-seward1
• [ ] @yurydelendik

Other Stakeholders

• [x] @bnjbvr

RFC notifications bot (Mar 26 2021 at 09:44):

uweigand commented on Issue #10:

I agree as well.

RFC notifications bot (Mar 26 2021 at 13:24):

yurydelendik edited a comment on Issue #10:

Motion to finalize with a disposition to merge

So there is not much discussion here, but there also seem to be few objections. Given that runtime perf is generally positive, compatibility check-boxes are complete, and the maintenance story improves greatly once this moves forward, I'm proposing that we merge this RFC.

Stakeholders sign-off

Tagging all employees of BA-affiliated companies who have committed to the Wasmtime or Lucet repos in the last three months, plus anyone who has given feedback on this PR as a stakeholder.

Fastly

• [x] @alexcrichton
• [x] @cfallin
• [x] @sunfishcode
• [x] @jedisct1
• [x] @fitzgen
• [x] @pchickey
• [ ] @peterhuene
• [ ] @acfoltzer
• [ ] @iximeow

Intel

• [x] @abrown
• [x] @jlb6740

IBM

• [ ] @uweigand

Mozilla

• [ ] @julian-seward1
• [x] @yurydelendik

Other Stakeholders

• [x] @bnjbvr

RFC notifications bot (Mar 26 2021 at 14:16):

tschneidereit edited a comment on Issue #10:

Motion to finalize with a disposition to merge

So there is not much discussion here, but there also seem to be few objections. Given that runtime perf is generally positive, compatibility check-boxes are complete, and the maintenance story improves greatly once this moves forward, I'm proposing that we merge this RFC.

Stakeholders sign-off

Tagging all employees of BA-affiliated companies who have committed to the Wasmtime or Lucet repos in the last three months, plus anyone who has given feedback on this PR as a stakeholder.

Fastly

• [x] @alexcrichton
• [x] @cfallin
• [x] @sunfishcode
• [x] @jedisct1
• [x] @fitzgen
• [x] @pchickey
• [ ] @peterhuene
• [ ] @acfoltzer
• [ ] @iximeow

Intel

• [x] @abrown
• [x] @jlb6740

IBM

• [x] @uweigand

Mozilla

• [ ] @julian-seward1
• [x] @yurydelendik

Other Stakeholders

• [x] @bnjbvr

RFC notifications bot (Mar 26 2021 at 16:16):

cfallin commented on Issue #10:

Thanks all! As we actually have a signoff from every group of stakeholders, it looks like we can close the FCP early and go ahead with the merge:

https://github.com/bytecodealliance/rfcs/blob/main/accepted/rfc-process.md#making-a-decision-merge-or-close

Finally, the RFC is automatically merged/close if either:
- The FCP elapses without any objections.
- A stakeholder from each group has signed off, short-cutting the waiting period.

Last updated: Dec 23 2024 at 13:07 UTC