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PageStorage: Fine grained lock on external callbacks (#5699) #5785

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ti-chi-bot
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This is an automated cherry-pick of #5699

What problem does this PR solve?

Issue Number: close #5697

Problem Summary:
The GC total time in logging does not include the time costs in clean_external_page.

In PageStorageImpl::gcImpl clean_external_page, we hold the callbacks_mutex until all external page gc done.

auto clean_external_page = [this]() {
std::scoped_lock lock{callbacks_mutex};
if (!callbacks_container.empty())
{
for (const auto & [ns_id, callbacks] : callbacks_container)
{
auto pending_external_pages = callbacks.scanner();
auto alive_external_ids = getAliveExternalPageIds(ns_id);
callbacks.remover(pending_external_pages, alive_external_ids);
}
}
};

while the time cost in clean_external_page is not ignorable and may block new StorageDeltaMerge from being created

void PageStorageImpl::registerExternalPagesCallbacks(const ExternalPageCallbacks & callbacks)
{
std::scoped_lock lock{callbacks_mutex};
assert(callbacks.scanner != nullptr);
assert(callbacks.remover != nullptr);
assert(callbacks.ns_id != MAX_NAMESPACE_ID);
assert(callbacks_container.count(callbacks.ns_id) == 0);
callbacks_container.emplace(callbacks.ns_id, callbacks);
}

// remember to unregister it when shutdown
storage_pool->dataRegisterExternalPagesCallbacks(callbacks);

What is changed and how it works?

  • Make the external pages cleaning callbacks safe even after table is dropped
  • Use shared_ptr to refine the lock granularity of running external cleaning callbacks, so that creating table won't be block by the whole processing time of cleanExternalPage.
  • Remove the non-atomic renaming table logic

Problem not yet resolve in this PR

Check List

Tests

  • Unit test
  • Integration test
  • Manual test (add detailed scripts or steps below)
  • No code

Side effects

  • Performance regression: Consumes more CPU
  • Performance regression: Consumes more Memory
  • Breaking backward compatibility

Documentation

  • Affects user behaviors
  • Contains syntax changes
  • Contains variable changes
  • Contains experimental features
  • Changes MySQL compatibility

Release note

Fix the bug that page GC may block creating tables

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@ti-chi-bot: This cherry pick PR is for a release branch and has not yet been approved by release team.
Adding the do-not-merge/cherry-pick-not-approved label.

To merge this cherry pick, it must first be approved by the collaborators.

AFTER it has been approved by collaborators, please ping the release team in a comment to request a cherry pick review.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

@ti-chi-bot ti-chi-bot added do-not-merge/cherry-pick-not-approved release-note Denotes a PR that will be considered when it comes time to generate release notes. size/XXL Denotes a PR that changes 1000+ lines, ignoring generated files. type/cherry-pick-for-release-6.1 This PR is cherry-picked to release-6.1 from a source PR. labels Sep 5, 2022
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do-not-merge/cherry-pick-not-approved release-note Denotes a PR that will be considered when it comes time to generate release notes. size/XXL Denotes a PR that changes 1000+ lines, ignoring generated files. type/cherry-pick-for-release-6.1 This PR is cherry-picked to release-6.1 from a source PR.
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