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Lazy loading of primary keys in memory#60093

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alexey-milovidov merged 13 commits intomasterfrom
lazy-primary-key-loading
Feb 19, 2024
Merged

Lazy loading of primary keys in memory#60093
alexey-milovidov merged 13 commits intomasterfrom
lazy-primary-key-loading

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@alexey-milovidov alexey-milovidov commented Feb 17, 2024 •
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Changelog category (leave one):

  • Performance Improvement

Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):

The tables' primary keys will be loaded in memory lazily on first access. This is controlled by the new MergeTree setting primary_key_lazy_load, which is on by default. This provides several advantages: - it will not be loaded for tables that are not used; - if there is not enough memory, an exception will be thrown on first use instead of at server startup. This provides several disadvantages: - the latency of loading the primary key will be paid on the first query rather than before accepting connections; this theoretically may introduce a thundering-herd problem. This closes #11188.

@robot-ch-test-poll robot-ch-test-poll added the pr-performance Pull request with some performance improvements label Feb 17, 2024
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robot-ch-test-poll commented Feb 17, 2024 •
edited by robot-clickhouse-ci-2
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This is an automated comment for commit 8d6e6d6 with description of existing statuses. It's updated for the latest CI running

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Successful checks
Check nameDescriptionStatus
AST fuzzerRuns randomly generated queries to catch program errors. The build type is optionally given in parenthesis. If it fails, ask a maintainer for help✅ success
ClickBenchRuns [ClickBench](https://github.com/ClickHouse/ClickBench/) with instant-attach table✅ success
ClickHouse build checkBuilds ClickHouse in various configurations for use in further steps. You have to fix the builds that fail. Build logs often has enough information to fix the error, but you might have to reproduce the failure locally. The cmake options can be found in the build log, grepping for cmake. Use these options and follow the general build process✅ success
Compatibility checkChecks that clickhouse binary runs on distributions with old libc versions. If it fails, ask a maintainer for help✅ success
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Docker server imageThe check to build and optionally push the mentioned image to docker hub✅ success
Docs checkBuilds and tests the documentation✅ success
Fast testNormally this is the first check that is ran for a PR. It builds ClickHouse and runs most of stateless functional tests, omitting some. If it fails, further checks are not started until it is fixed. Look at the report to see which tests fail, then reproduce the failure locally as described here✅ success
Flaky testsChecks if new added or modified tests are flaky by running them repeatedly, in parallel, with more randomization. Functional tests are run 100 times with address sanitizer, and additional randomization of thread scheduling. Integrational tests are run up to 10 times. If at least once a new test has failed, or was too long, this check will be red. We don't allow flaky tests, read the doc✅ success
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Integration testsThe integration tests report. In parenthesis the package type is given, and in square brackets are the optional part/total tests✅ success
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Performance ComparisonMeasure changes in query performance. The performance test report is described in detail here. In square brackets are the optional part/total tests✅ success
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SQLancerFuzzing tests that detect logical bugs with SQLancer tool✅ success
SqllogicRun clickhouse on the sqllogic test set against sqlite and checks that all statements are passed✅ success
Stateful testsRuns stateful functional tests for ClickHouse binaries built in various configurations -- release, debug, with sanitizers, etc✅ success
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Stateless testsRuns stateless functional tests for ClickHouse binaries built in various configurations -- release, debug, with sanitizers, etc❌ failure
Stress testRuns stateless functional tests concurrently from several clients to detect concurrency-related errors❌ failure

CurtizJ
CurtizJ reviewed Feb 17, 2024
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@CurtizJ CurtizJ self-assigned this Feb 17, 2024
@alexey-milovidov alexey-milovidov merged commit 6c2c171 into master Feb 19, 2024
@alexey-milovidov alexey-milovidov deleted the lazy-primary-key-loading branch February 19, 2024 00:36
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antonio2368 commented Feb 19, 2024

Race probably introduced by this PR https://s3.amazonaws.com/clickhouse-test-reports/59460/0be66e95762ed82f971be3dc64e783fcb279abf3/stateless_tests__tsan__s3_storage_/stderr.log

@antonio2368 antonio2368 mentioned this pull request Feb 19, 2024
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tavplubix commented Feb 19, 2024

Race probably introduced by this PR https://s3.amazonaws.com/clickhouse-test-reports/59460/0be66e95762ed82f971be3dc64e783fcb279abf3/stateless_tests__tsan__s3_storage_/stderr.log

And it was even found by the CI in the last commit in this PR: https://s3.amazonaws.com/clickhouse-test-reports/60093/8d6e6d67ed8b529794ef9ef7585d60c446df2d57/stateless_tests__tsan__s3_storage_/stderr.log

@alexey-milovidov, please don't forget to check CI failures before merging

@robot-ch-test-poll4 robot-ch-test-poll4 added the pr-synced-to-cloud The PR is synced to the cloud repo label Feb 19, 2024
@robot-ch-test-poll3 robot-ch-test-poll3 added the pr-backports-created-cloud deprecated label, NOOP label Feb 23, 2024
@nikitamikhaylov nikitamikhaylov mentioned this pull request Mar 1, 2024
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@pamarcos pamarcos mentioned this pull request Apr 18, 2024
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Protection from too large size of index in memory.

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