The buf_pool.flush_list_mutex became more contended after MDEV-27868 fixed a correctness issue that was caused by the performance fix MDEV-27774. We really should acquire and release buf_pool.flush_list_mutex at most once in mtr_t::commit() and reduce the amount of work performed while holding the mutex.
{"report":{"fcp":721.2000000476837,"ttfb":206.90000009536743,"pageVisibility":"visible","entityId":111440,"key":"jira.project.issue.view-issue","isInitial":true,"threshold":1000,"elementTimings":{},"userDeviceMemory":8,"userDeviceProcessors":64,"apdex":1,"journeyId":"de31325d-8bd5-49f7-a343-bcbe3e7b21a3","navigationType":0,"readyForUser":792.2000000476837,"redirectCount":0,"resourceLoadedEnd":764.8000001907349,"resourceLoadedStart":212.20000004768372,"resourceTiming":[{"duration":6.5,"initiatorType":"link","name":"https://jira.mariadb.org/s/2c21342762a6a02add1c328bed317ffd-CDN/lu2bu7/820016/12ta74/0a8bac35585be7fc6c9cc5a0464cd4cf/_/download/contextbatch/css/_super/batch.css","startTime":212.20000004768372,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":212.20000004768372,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":218.70000004768372,"responseStart":0,"secureConnectionStart":0},{"duration":6.5,"initiatorType":"link","name":"https://jira.mariadb.org/s/7ebd35e77e471bc30ff0eba799ebc151-CDN/lu2bu7/820016/12ta74/8679b4946efa1a0bb029a3a22206fb5d/_/download/contextbatch/css/jira.browse.project,project.issue.navigator,jira.view.issue,jira.general,jira.global,atl.general,-_super/batch.css?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&slack-enabled=true","startTime":212.5,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":212.5,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":219,"responseStart":0,"secureConnectionStart":0},{"duration":60.5,"initiatorType":"script","name":"https://jira.mariadb.org/s/fbf975c0cce4b1abf04784eeae9ba1f4-CDN/lu2bu7/820016/12ta74/0a8bac35585be7fc6c9cc5a0464cd4cf/_/download/contextbatch/js/_super/batch.js?locale=en","startTime":212.60000014305115,"connectEnd":212.60000014305115,"connectStart":212.60000014305115,"domainLookupEnd":212.60000014305115,"domainLookupStart":212.60000014305115,"fetchStart":212.60000014305115,"redirectEnd":0,"redirectStart":0,"requestStart":212.60000014305115,"responseEnd":273.10000014305115,"responseStart":273.10000014305115,"secureConnectionStart":212.60000014305115},{"duration":145.29999995231628,"initiatorType":"script","name":"https://jira.mariadb.org/s/099b33461394b8015fc36c0a4b96e19f-CDN/lu2bu7/820016/12ta74/8679b4946efa1a0bb029a3a22206fb5d/_/download/contextbatch/js/jira.browse.project,project.issue.navigator,jira.view.issue,jira.general,jira.global,atl.general,-_super/batch.js?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&locale=en&slack-enabled=true","startTime":212.80000019073486,"connectEnd":212.80000019073486,"connectStart":212.80000019073486,"domainLookupEnd":212.80000019073486,"domainLookupStart":212.80000019073486,"fetchStart":212.80000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":212.80000019073486,"responseEnd":358.10000014305115,"responseStart":358.10000014305115,"secureConnectionStart":212.80000019073486},{"duration":148.90000009536743,"initiatorType":"script","name":"https://jira.mariadb.org/s/94c15bff32baef80f4096a08aceae8bc-CDN/lu2bu7/820016/12ta74/c92c0caa9a024ae85b0ebdbed7fb4bd7/_/download/contextbatch/js/atl.global,-_super/batch.js?locale=en","startTime":212.90000009536743,"connectEnd":212.90000009536743,"connectStart":212.90000009536743,"domainLookupEnd":212.90000009536743,"domainLookupStart":212.90000009536743,"fetchStart":212.90000009536743,"redirectEnd":0,"redirectStart":0,"requestStart":212.90000009536743,"responseEnd":361.80000019073486,"responseStart":361.7000000476837,"secureConnectionStart":212.90000009536743},{"duration":149.29999995231628,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2bu7/820016/12ta74/1.0/_/download/batch/jira.webresources:calendar-en/jira.webresources:calendar-en.js","startTime":212.90000009536743,"connectEnd":212.90000009536743,"connectStart":212.90000009536743,"domainLookupEnd":212.90000009536743,"domainLookupStart":212.90000009536743,"fetchStart":212.90000009536743,"redirectEnd":0,"redirectStart":0,"requestStart":212.90000009536743,"responseEnd":362.2000000476837,"responseStart":362.2000000476837,"secureConnectionStart":212.90000009536743},{"duration":149.60000014305115,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2bu7/820016/12ta74/1.0/_/download/batch/jira.webresources:calendar-localisation-moment/jira.webresources:calendar-localisation-moment.js","startTime":213,"connectEnd":213,"connectStart":213,"domainLookupEnd":213,"domainLookupStart":213,"fetchStart":213,"redirectEnd":0,"redirectStart":0,"requestStart":213,"responseEnd":362.60000014305115,"responseStart":362.60000014305115,"secureConnectionStart":213},{"duration":149.79999995231628,"initiatorType":"link","name":"https://jira.mariadb.org/s/b04b06a02d1959df322d9cded3aeecc1-CDN/lu2bu7/820016/12ta74/a2ff6aa845ffc9a1d22fe23d9ee791fc/_/download/contextbatch/css/jira.global.look-and-feel,-_super/batch.css","startTime":213.20000004768372,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":213.20000004768372,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":363,"responseStart":0,"secureConnectionStart":0},{"duration":149.79999995231628,"initiatorType":"script","name":"https://jira.mariadb.org/rest/api/1.0/shortcuts/820016/47140b6e0a9bc2e4913da06536125810/shortcuts.js?context=issuenavigation&context=issueaction","startTime":213.20000004768372,"connectEnd":213.20000004768372,"connectStart":213.20000004768372,"domainLookupEnd":213.20000004768372,"domainLookupStart":213.20000004768372,"fetchStart":213.20000004768372,"redirectEnd":0,"redirectStart":0,"requestStart":213.20000004768372,"responseEnd":363,"responseStart":363,"secureConnectionStart":213.20000004768372},{"duration":150.09999990463257,"initiatorType":"link","name":"https://jira.mariadb.org/s/3ac36323ba5e4eb0af2aa7ac7211b4bb-CDN/lu2bu7/820016/12ta74/d176f0986478cc64f24226b3d20c140d/_/download/contextbatch/css/com.atlassian.jira.projects.sidebar.init,-_super,-project.issue.navigator,-jira.view.issue/batch.css?jira.create.linked.issue=true","startTime":213.30000019073486,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":213.30000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":363.40000009536743,"responseStart":0,"secureConnectionStart":0},{"duration":150.10000014305115,"initiatorType":"script","name":"https://jira.mariadb.org/s/3339d87fa2538a859872f2df449bf8d0-CDN/lu2bu7/820016/12ta74/d176f0986478cc64f24226b3d20c140d/_/download/contextbatch/js/com.atlassian.jira.projects.sidebar.init,-_super,-project.issue.navigator,-jira.view.issue/batch.js?jira.create.linked.issue=true&locale=en","startTime":213.5,"connectEnd":213.5,"connectStart":213.5,"domainLookupEnd":213.5,"domainLookupStart":213.5,"fetchStart":213.5,"redirectEnd":0,"redirectStart":0,"requestStart":213.5,"responseEnd":363.60000014305115,"responseStart":363.60000014305115,"secureConnectionStart":213.5},{"duration":396.89999985694885,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2bu7/820016/12ta74/1.0/_/download/batch/jira.webresources:bigpipe-js/jira.webresources:bigpipe-js.js","startTime":214.30000019073486,"connectEnd":214.30000019073486,"connectStart":214.30000019073486,"domainLookupEnd":214.30000019073486,"domainLookupStart":214.30000019073486,"fetchStart":214.30000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":214.30000019073486,"responseEnd":611.2000000476837,"responseStart":611.2000000476837,"secureConnectionStart":214.30000019073486},{"duration":415.5,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2bu7/820016/12ta74/1.0/_/download/batch/jira.webresources:bigpipe-init/jira.webresources:bigpipe-init.js","startTime":214.40000009536743,"connectEnd":214.40000009536743,"connectStart":214.40000009536743,"domainLookupEnd":214.40000009536743,"domainLookupStart":214.40000009536743,"fetchStart":214.40000009536743,"redirectEnd":0,"redirectStart":0,"requestStart":214.40000009536743,"responseEnd":629.9000000953674,"responseStart":629.9000000953674,"secureConnectionStart":214.40000009536743},{"duration":184.29999995231628,"initiatorType":"xmlhttprequest","name":"https://jira.mariadb.org/rest/webResources/1.0/resources","startTime":427.30000019073486,"connectEnd":427.30000019073486,"connectStart":427.30000019073486,"domainLookupEnd":427.30000019073486,"domainLookupStart":427.30000019073486,"fetchStart":427.30000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":427.30000019073486,"responseEnd":611.6000001430511,"responseStart":611.6000001430511,"secureConnectionStart":427.30000019073486},{"duration":21.5,"initiatorType":"link","name":"https://jira.mariadb.org/s/d5715adaadd168a9002b108b2b039b50-CDN/lu2bu7/820016/12ta74/be4b45e9cec53099498fa61c8b7acba4/_/download/contextbatch/css/jira.project.sidebar,-_super,-project.issue.navigator,-jira.general,-jira.browse.project,-jira.view.issue,-jira.global,-atl.general,-com.atlassian.jira.projects.sidebar.init/batch.css?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&slack-enabled=true","startTime":642.8000001907349,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":642.8000001907349,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":664.3000001907349,"responseStart":0,"secureConnectionStart":0},{"duration":108.5,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2bu7/820016/12ta74/e65b778d185daf5aee24936755b43da6/_/download/contextbatch/js/browser-metrics-plugin.contrib,-_super,-project.issue.navigator,-jira.view.issue,-atl.general/batch.js?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&slack-enabled=true","startTime":643.6000001430511,"connectEnd":643.6000001430511,"connectStart":643.6000001430511,"domainLookupEnd":643.6000001430511,"domainLookupStart":643.6000001430511,"fetchStart":643.6000001430511,"redirectEnd":0,"redirectStart":0,"requestStart":643.6000001430511,"responseEnd":752.1000001430511,"responseStart":752.1000001430511,"secureConnectionStart":643.6000001430511},{"duration":120.80000019073486,"initiatorType":"script","name":"https://jira.mariadb.org/s/f51ef5507eea4c158f257c66c93b2a3f-CDN/lu2bu7/820016/12ta74/be4b45e9cec53099498fa61c8b7acba4/_/download/contextbatch/js/jira.project.sidebar,-_super,-project.issue.navigator,-jira.general,-jira.browse.project,-jira.view.issue,-jira.global,-atl.general,-com.atlassian.jira.projects.sidebar.init/batch.js?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&locale=en&slack-enabled=true","startTime":644,"connectEnd":644,"connectStart":644,"domainLookupEnd":644,"domainLookupStart":644,"fetchStart":644,"redirectEnd":0,"redirectStart":0,"requestStart":644,"responseEnd":764.8000001907349,"responseStart":764.8000001907349,"secureConnectionStart":644},{"duration":67.90000009536743,"initiatorType":"script","name":"https://www.google-analytics.com/analytics.js","startTime":714.5,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":714.5,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":782.4000000953674,"responseStart":0,"secureConnectionStart":0},{"duration":69.5,"initiatorType":"xmlhttprequest","name":"https://jira.mariadb.org/rest/webResources/1.0/resources","startTime":737.8000001907349,"connectEnd":737.8000001907349,"connectStart":737.8000001907349,"domainLookupEnd":737.8000001907349,"domainLookupStart":737.8000001907349,"fetchStart":737.8000001907349,"redirectEnd":0,"redirectStart":0,"requestStart":737.8000001907349,"responseEnd":807.3000001907349,"responseStart":807.3000001907349,"secureConnectionStart":737.8000001907349}],"fetchStart":0,"domainLookupStart":0,"domainLookupEnd":0,"connectStart":0,"connectEnd":0,"requestStart":77,"responseStart":207,"responseEnd":209,"domLoading":210,"domInteractive":858,"domContentLoadedEventStart":858,"domContentLoadedEventEnd":904,"domComplete":1045,"loadEventStart":1045,"loadEventEnd":1046,"userAgent":"Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)","marks":[{"name":"bigPipe.sidebar-id.start","time":826.6000001430511},{"name":"bigPipe.sidebar-id.end","time":827.3000001907349},{"name":"bigPipe.activity-panel-pipe-id.start","time":827.5},{"name":"bigPipe.activity-panel-pipe-id.end","time":828.7000000476837},{"name":"activityTabFullyLoaded","time":916.4000000953674}],"measures":[],"correlationId":"f219d39263e3ee","effectiveType":"4g","downlink":10,"rtt":0,"serverDuration":82,"dbReadsTimeInMs":12,"dbConnsTimeInMs":20,"applicationHash":"9d11dbea5f4be3d4cc21f03a88dd11d8c8687422","experiments":[]}}
My first attempt at fixing this could still be improved upon, by refactoring ReleaseModified and its caller so that buf_pool.flush_list_mutex will be acquired and released exactly once, and the correct insert position will be determined only once in case multiple previously clean pages were modified.