rustdoc-search: yet another stringdex optimization attempt

[notriddle]

This one's uses a different tactic. It shouldn't significantly increase the amount of downloaded index data, but still reduces the amount of disk usage.

This one works by changing the suffix-only node representation to omit some data that's needed for checking. Since those nodes make up the bulk of the tree, it reduces the data they store, but also requires validating the match by fetching the name itself (but the names list is pretty small, and when I tried it with wordnet "indexing" it was about the same).

r? @GuillaumeGomez

[rustbot]

These commits modify the Cargo.lock file. Unintentional changes to Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
Otherwise, you can ignore this comment.

Some changes occurred in HTML/CSS/JS.

cc @GuillaumeGomez, @jsha, @lolbinarycat

[notriddle]

@bors try @rust-timer queue

[klensy]

N.B. pin stringdex version when updated next time, so it won't fail weekly dep updates.

[rust-bors]

☀️ Try build successful (CI)
Build commit: b96101a (b96101aded737860cab9b6e77634f4563f5100cb, parent: 176d8dbce6a7a7a4541d1c980d4a85dfb76ce1f1)

[rust-timer]

Finished benchmarking commit (b96101a): comparison URL.

Overall result: ❌✅ regressions and improvements - please read the text below

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @rustbot label: +perf-regression-triaged. If not, please fix the regressions and do another perf run. If its results are neutral or positive, the label will be automatically removed.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	2.9%	[2.9%, 2.9%]	1
Regressions ❌ (secondary)	1.2%	[1.2%, 1.2%]	1
Improvements ✅ (primary)	-1.1%	[-1.1%, -1.1%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.9%	[-1.1%, 2.9%]	2

Max RSS (memory usage)

This benchmark run did not return any relevant results for this metric.

Cycles

Results (secondary 3.8%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	3.8%	[3.8%, 3.8%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Binary size

Results (secondary -0.0%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.0%	[-0.0%, -0.0%]	1
All ❌✅ (primary)	-	-	0

Bootstrap: 467.709s -> 467.04s (-0.14%)
Artifact size: 391.16 MiB -> 391.21 MiB (0.01%)

[notriddle]

@bors try @rust-timer queue

[rust-bors]

☀️ Try build successful (CI)
Build commit: 8689c32 (8689c329d651928f18c308f946f14f54995111a6, parent: 35d55b34bffd51384ac430cc20852b7d16dd5a90)

[rust-timer]

Finished benchmarking commit (8689c32): comparison URL.

Overall result: ❌✅ regressions and improvements - please read the text below

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @rustbot label: +perf-regression-triaged. If not, please fix the regressions and do another perf run. If its results are neutral or positive, the label will be automatically removed.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	1.1%	[0.1%, 3.1%]	3
Regressions ❌ (secondary)	0.4%	[0.1%, 0.8%]	3
Improvements ✅ (primary)	-1.2%	[-1.2%, -1.2%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.5%	[-1.2%, 3.1%]	4

Max RSS (memory usage)

Results (primary -2.4%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-2.4%	[-2.4%, -2.4%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.4%	[-2.4%, -2.4%]	1

Cycles

This benchmark run did not return any relevant results for this metric.

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 466.374s -> 466.216s (-0.03%)
Artifact size: 388.50 MiB -> 388.54 MiB (0.01%)