[7.0.0] Fix analysis time regression with Bzlmod lockfile #20021
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This commit fixes a regression in analysis time caused by 19c0c80. Since `BazelModuleResolutionEvent` and `ModuleExtensionResolutionEvent` are both marked as `storeForReplay`, they are stored in a nested set for essentially all analysis phase nodes. This resulted in frequent (i.e., per target) calls to their `hashCode` methods, which are not cached and delegated to the likewise uncached methods on large `ImmutableMap` and `ImmutableTable` instances. Since there is no need for these events to be deduplicated, switching to reference equality resolves this issue. The following analysis phase measurements for a synthetic project with a single "hub and spokes" module extension and 2,000 repos illustrate the effect: * without lockfile: 4.3s * with lockfile before this commit: 8.3s * with lockfile after this commit: 4.2s Fixes bazelbuild#19952 Closes bazelbuild#19970. PiperOrigin-RevId: 578734010 Change-Id: I870867c5c509389632793b0d5fe5c43ddc6176f3
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This commit fixes a regression in analysis time caused by 19c0c80. Since
BazelModuleResolutionEventandModuleExtensionResolutionEventare both marked asstoreForReplay, they are stored in a nested set for essentially all analysis phase nodes. This resulted in frequent (i.e., per target) calls to theirhashCodemethods, which are not cached and delegated to the likewise uncached methods on largeImmutableMapandImmutableTableinstances.Since there is no need for these events to be deduplicated, switching to reference equality resolves this issue.
The following analysis phase measurements for a synthetic project with a single "hub and spokes" module extension and 2,000 repos illustrate the effect:
Fixes #19952
Closes #19970.
Commit 435d1c2
PiperOrigin-RevId: 578734010
Change-Id: I870867c5c509389632793b0d5fe5c43ddc6176f3