') + ')', 'gi'); if (regex.test(text)) { found = true; var frag = document.createDocumentFragment(); var parts = text.split(regex); parts.forEach(function(part, i) { if (i % 2 === 0) { frag.appendChild(document.createTextNode(part)); } else { var span = document.createElement('span'); span.className = 'userscript-highlight'; span.textContent = part; frag.appendChild(span); } }); node.parentNode.replaceChild(frag, node); } }); } else if (node.nodeType === 1 && node.childNodes) { // element var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT']; if (!skipTags.includes(node.tagName)) { Array.from(node.childNodes).forEach(highlight); } } } highlight(document.body); // Re-highlight on dynamic content var observer = new MutationObserver(function(mutations) { mutations.forEach(function(m) { m.addedNodes.forEach(function(node) { if (node.nodeType === 1 || node.nodeType === 3) highlight(node); }); }); }); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ', 'i'); if (__m === '*' || __re.test(location.href)) { // Strip utm_, fbclid, gclid, etc. from all links on page (function() { var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content', 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid', 'ref', 'ref_src', 'source', 'medium', 'campaign']; function cleanUrl(url) { try { var u = new URL(url, window.location.origin); var changed = false; trackingParams.forEach(function(p) { if (u.searchParams.has(p)) { u.searchParams.delete(p); changed = true; } }); return changed ? u.toString() : url; } catch (e) { return url; } } function cleanLinks() { document.querySelectorAll('a[href]').forEach(function(a) { var clean = cleanUrl(a.href); if (clean !== a.href) a.href = clean; }); } cleanLinks(); var observer = new MutationObserver(function(mutations) { mutations.forEach(function(m) { m.addedNodes.forEach(function(node) { if (node.nodeType === 1) { if (node.tagName === 'A') cleanLinks(); node.querySelectorAll('a[href]').forEach(function(a) { var clean = cleanUrl(a.href); if (clean !== a.href) a.href = clean; }); } }); }); }); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + ', 'i'); if (__m === '*' || __re.test(location.href)) { // Auto-enable theater mode on YouTube (function() { function tryTheater() { var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]'); if (btn && !btn.classList.contains('activated')) { btn.click(); } } // Try immediately tryTheater(); // Try after navigation (SPA) var lastUrl = location.href; setInterval(function() { if (location.href !== lastUrl) { lastUrl = location.href; setTimeout(tryTheater, 500); } }, 1000); // Also try on player load var observer = new MutationObserver(tryTheater); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ', 'i'); if (__m === '*' || __re.test(location.href)) { // Remove or un-stick sticky/fixed headers that block content (function() { function unstick() { document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) { if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') { el.style.position = 'static'; el.style.top = 'auto'; el.style.zIndex = 'auto'; } }); } unstick(); var observer = new MutationObserver(unstick); observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] }); })(); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); })(); Perf optimization of module scanning for generic cycle detection by trylek · Pull Request #87532 · dotnet/runtime · GitHub
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Perf optimization of module scanning for generic cycle detection - #87532

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Perf optimization of module scanning for generic cycle detection#87532
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trylek:GenericCycleDetectorSpeedup

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@trylek

@trylektrylek commented Jun 13, 2023

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As part of investigation of the bug #66079 and implementation of the fix#71426 I noticed that one aggravating factor is that Crossgen2 starts analyzing the same assembly multiple times on its various parallel threads; this busywork additionally makes the app compete for access to the same metadata, making the initial analysis even slower.

In accordance with Michal's suggestion from the PR thread #71426 I propose to modify the generic cycle detector to run the initial analysis single-threaded if the module in question is expected to be "generics-heavy" using the number of TypeSpec rows in its ECMA metadata as an indicator of module generic complexity.

I have written a simple managed app scanning all runtime framework assemblies, ASP.NET assemblies and assemblies used in internal CoreCLR testing. I found out that the largest number of TypeSpec rows is in FSharp.Core (3855), followed by Microsoft.CodeAnalysis (3148). Based on these findings I have set the initial value of the cutoff for single-threaded analysis to 5000.

Thanks

Tomas

/cc @dotnet/crossgen-contrib

@trylek
Perf optimization of module scanning for generic cycle detection
8638895
As part of investigation of the bug dotnet#66079 and implementation of
the fixdotnet#71426 I noticed that one aggravating factor is that
Crossgen2 starts analyzing the same assembly multiple times on
its various parallel threads; this busywork additionally makes the
app compete for access to the same metadata, making the initial
analysis even slower.
In accordance with Michal's suggestion from the PR thread dotnet#71426
I propose to modify the generic cycle detector to run the initial
analysis single-threaded if the module in question is expected
to be "generics-heavy" using the number of TypeSpec rows in its
ECMA metadata as an indicator of module generic complexity.
I have written a simple managed app scanning all runtime framework
assemblies, ASP.NET assemblies and assemblies used in internal
CoreCLR testing. I found out that the largest number of TypeSpec
rows is in FSharp.Core (3855), followed by Microsoft.CodeAnalysis
(3148). Based on these findings I have set the initial value of
the cutoff for single-threaded analysis to 5000.
Thanks
Tomas
@ghostghost added the area-ReadyToRun label Jun 13, 2023
@ghostghost assigned trylekJun 13, 2023
@trylek

trylek commented Jun 13, 2023

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With this change, compilation of the repro case from #66079 goes down from about 8 to 2 minutes (with --enable-generic-cycle-detection and no overrides to the detailed cutoff values).

MichalStrehovsky
MichalStrehovsky reviewed Jun 14, 2023
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Comment threadsrc/coreclr/tools/Common/Compiler/GenericCycleDetection/ModuleCycleInfo.cs
}
else
{
lock (ownerModule)

@MichalStrehovskyMichalStrehovskyJun 14, 2023

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We'd need to remember that nobody else should lock on EcmaModules so that we don't get an accidental deadlock somewhere.

I don't have strong opinions about this - the compilation will finish even without doing this and whether it take 2 minutes or 8 minutes doesn't make a huge difference - it's already orders of magnitude longer than usual - the assembly is simply AOT hostile and it will cause trouble for any AOT we have in .NET (NativeAOT, Mono AOT, crossgen2). I would be fine won't fixing that part.

@MichalStrehovskyMichalStrehovsky mentioned this pull request Jun 22, 2023
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@trylek

trylek commented Jul 17, 2023

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Closing as there is no clear benefit in taking this change - it only covers a niche case that is unfriendly to AOT compilation one way or the other.

@trylektrylek closed this Jul 17, 2023
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