Future of --use-largepages=on #64408

Closed
#65389
Closed
Future of --use-largepages=on#64408
#65389
Labels
memoryIssues and PRs related to Node.js memory management or memory footprint.metaIssues and PRs related to the general management of the project.

Description

@joyeecheung
joyeecheung
opened on Jul 10, 2026

This was added back in 2018, some background can be found in this issue #16198 - from what I can tell we opted into a user-land relocation to work around the fact that for most kernels in the wild, file-backed .text THP won't work out of the box (i.e. CONFIG_READ_ONLY_THP_FOR_FS still isn't on in the mainstream distros most commonly deployed even in 2026, also it is being removed, there are some alternatives though)

Currently the --use-largepages implementation incurs two problems:

  1. It breaks the Node.js binary on WSL1 linux x64 release binary fails to exec on WSL1 #63735
  2. It will stop working in Node.js after we roll in https://chromium-review.googlesource.com/c/v8/v8/+/7985687

2 would be tricky to deal with, it's an optimization that removed the /proc/self/maps parsing overhead and simply rely on address equality of the embedded blob to detect whether it's file-backed, the current method --use-largepages uses to relocate the text region doesn't change the address equality even though the blob is no longer file-backed after relocation, hence it will crash because MREMAP_DONTUNMAP will zero out non-file-backed memory.

From what I can think of we have a few choices:

  1. Convince the upstream to handle the case when the embedded blob is address-equal to the default blob, but is not actually file-backed. From what I can think of this can only be implemented by re-introducing some file parsing overhead (e.g. at least /proc/self/pagemap) to the isolate group initialization process, defeating the optimization added in that CL.
  2. Add a flag to V8 to enforce checking the blob is file-backed via more robust measures other than address equality, then on the Node.js side, enable that flag when --use-largepages=on
  3. Reimplement --use-largepages=on by relocating the .text to memory backed by memfd instead of an anonymous memory, then MREMAP_DONTUNMAP won't zero out the memory

I think 2 and 3 are probably more viable/have less downsides. But since so far it doesn't look like --use-largepages=on is used a lot in the wild, and the alignment in the build it needs breaks WSL1, it also raises another question: do we even want to keep maintaining it? So there's also option 4:

  1. Make --use-largepages=on a no-op (it can already be a no-op because MADV_HUGEPAGE is only advisory, so the feature only ever works on a best-effort basis), and deprecate it eventually.

Opening an issue to see if there's any usage of this feature or if there are other ideas to deal with this. If there are real-world users of this feature it may still be worth it to do 2 or 3, but if there are none, we are probably better off deprecating it to cut the maintenance burden (that is not to say to completely say goodbye to work in this line once and for all, but it should be experimented differently other than an opt-in flag that nobody seems to be deploying).

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      , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
       blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

      Skip to content
      Future of --use-largepages=on #64408
      Closed
      #65389
      Closed
      Future of --use-largepages=on#64408
      #65389
      Labels
      memoryIssues and PRs related to Node.js memory management or memory footprint.metaIssues and PRs related to the general management of the project.
      Description
      @joyeecheung
      joyeecheung
      opened on Jul 10, 2026
      This was added back in 2018, some background can be found in this issue #16198 - from what I can tell we opted into a user-land relocation to work around the fact that for most kernels in the wild, file-backed .text THP won't work out of the box (i.e. CONFIG_READ_ONLY_THP_FOR_FS still isn't on in the mainstream distros most commonly deployed even in 2026, also it is being removed, there are some alternatives though)
      Currently the --use-largepages implementation incurs two problems:
      1. It breaks the Node.js binary on WSL1 linux x64 release binary fails to exec on WSL1 #63735
      2. It will stop working in Node.js after we roll in https://chromium-review.googlesource.com/c/v8/v8/+/7985687
      2 would be tricky to deal with, it's an optimization that removed the /proc/self/maps parsing overhead and simply rely on address equality of the embedded blob to detect whether it's file-backed, the current method --use-largepages uses to relocate the text region doesn't change the address equality even though the blob is no longer file-backed after relocation, hence it will crash because MREMAP_DONTUNMAP will zero out non-file-backed memory.
      From what I can think of we have a few choices:
      1. Convince the upstream to handle the case when the embedded blob is address-equal to the default blob, but is not actually file-backed. From what I can think of this can only be implemented by re-introducing some file parsing overhead (e.g. at least /proc/self/pagemap) to the isolate group initialization process, defeating the optimization added in that CL.
      2. Add a flag to V8 to enforce checking the blob is file-backed via more robust measures other than address equality, then on the Node.js side, enable that flag when --use-largepages=on
      3. Reimplement --use-largepages=on by relocating the .text to memory backed by memfd instead of an anonymous memory, then MREMAP_DONTUNMAP won't zero out the memory
      I think 2 and 3 are probably more viable/have less downsides. But since so far it doesn't look like --use-largepages=on is used a lot in the wild, and the alignment in the build it needs breaks WSL1, it also raises another question: do we even want to keep maintaining it? So there's also option 4:
      1. Make --use-largepages=on a no-op (it can already be a no-op because MADV_HUGEPAGE is only advisory, so the feature only ever works on a best-effort basis), and deprecate it eventually.
      Opening an issue to see if there's any usage of this feature or if there are other ideas to deal with this. If there are real-world users of this feature it may still be worth it to do 2 or 3, but if there are none, we are probably better off deprecating it to cut the maintenance burden (that is not to say to completely say goodbye to work in this line once and for all, but it should be experimented differently other than an opt-in flag that nobody seems to be deploying).
      Activity
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

          Skip to content
          Future of --use-largepages=on #64408
          Closed
          #65389
          Closed
          Future of --use-largepages=on#64408
          #65389
          Labels
          memoryIssues and PRs related to Node.js memory management or memory footprint.metaIssues and PRs related to the general management of the project.
          Description
          @joyeecheung
          joyeecheung
          opened on Jul 10, 2026
          This was added back in 2018, some background can be found in this issue #16198 - from what I can tell we opted into a user-land relocation to work around the fact that for most kernels in the wild, file-backed .text THP won't work out of the box (i.e. CONFIG_READ_ONLY_THP_FOR_FS still isn't on in the mainstream distros most commonly deployed even in 2026, also it is being removed, there are some alternatives though)
          Currently the --use-largepages implementation incurs two problems:
          1. It breaks the Node.js binary on WSL1 linux x64 release binary fails to exec on WSL1 #63735
          2. It will stop working in Node.js after we roll in https://chromium-review.googlesource.com/c/v8/v8/+/7985687
          2 would be tricky to deal with, it's an optimization that removed the /proc/self/maps parsing overhead and simply rely on address equality of the embedded blob to detect whether it's file-backed, the current method --use-largepages uses to relocate the text region doesn't change the address equality even though the blob is no longer file-backed after relocation, hence it will crash because MREMAP_DONTUNMAP will zero out non-file-backed memory.
          From what I can think of we have a few choices:
          1. Convince the upstream to handle the case when the embedded blob is address-equal to the default blob, but is not actually file-backed. From what I can think of this can only be implemented by re-introducing some file parsing overhead (e.g. at least /proc/self/pagemap) to the isolate group initialization process, defeating the optimization added in that CL.
          2. Add a flag to V8 to enforce checking the blob is file-backed via more robust measures other than address equality, then on the Node.js side, enable that flag when --use-largepages=on
          3. Reimplement --use-largepages=on by relocating the .text to memory backed by memfd instead of an anonymous memory, then MREMAP_DONTUNMAP won't zero out the memory
          I think 2 and 3 are probably more viable/have less downsides. But since so far it doesn't look like --use-largepages=on is used a lot in the wild, and the alignment in the build it needs breaks WSL1, it also raises another question: do we even want to keep maintaining it? So there's also option 4:
          1. Make --use-largepages=on a no-op (it can already be a no-op because MADV_HUGEPAGE is only advisory, so the feature only ever works on a best-effort basis), and deprecate it eventually.
          Opening an issue to see if there's any usage of this feature or if there are other ideas to deal with this. If there are real-world users of this feature it may still be worth it to do 2 or 3, but if there are none, we are probably better off deprecating it to cut the maintenance burden (that is not to say to completely say goodbye to work in this line once and for all, but it should be experimented differently other than an opt-in flag that nobody seems to be deploying).
          Activity
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

              Skip to content
              Future of --use-largepages=on #64408
              Closed
              #65389
              Closed
              Future of --use-largepages=on#64408
              #65389
              Labels
              memoryIssues and PRs related to Node.js memory management or memory footprint.metaIssues and PRs related to the general management of the project.
              Description
              @joyeecheung
              joyeecheung
              opened on Jul 10, 2026
              This was added back in 2018, some background can be found in this issue #16198 - from what I can tell we opted into a user-land relocation to work around the fact that for most kernels in the wild, file-backed .text THP won't work out of the box (i.e. CONFIG_READ_ONLY_THP_FOR_FS still isn't on in the mainstream distros most commonly deployed even in 2026, also it is being removed, there are some alternatives though)
              Currently the --use-largepages implementation incurs two problems:
              1. It breaks the Node.js binary on WSL1 linux x64 release binary fails to exec on WSL1 #63735
              2. It will stop working in Node.js after we roll in https://chromium-review.googlesource.com/c/v8/v8/+/7985687
              2 would be tricky to deal with, it's an optimization that removed the /proc/self/maps parsing overhead and simply rely on address equality of the embedded blob to detect whether it's file-backed, the current method --use-largepages uses to relocate the text region doesn't change the address equality even though the blob is no longer file-backed after relocation, hence it will crash because MREMAP_DONTUNMAP will zero out non-file-backed memory.
              From what I can think of we have a few choices:
              1. Convince the upstream to handle the case when the embedded blob is address-equal to the default blob, but is not actually file-backed. From what I can think of this can only be implemented by re-introducing some file parsing overhead (e.g. at least /proc/self/pagemap) to the isolate group initialization process, defeating the optimization added in that CL.
              2. Add a flag to V8 to enforce checking the blob is file-backed via more robust measures other than address equality, then on the Node.js side, enable that flag when --use-largepages=on
              3. Reimplement --use-largepages=on by relocating the .text to memory backed by memfd instead of an anonymous memory, then MREMAP_DONTUNMAP won't zero out the memory
              I think 2 and 3 are probably more viable/have less downsides. But since so far it doesn't look like --use-largepages=on is used a lot in the wild, and the alignment in the build it needs breaks WSL1, it also raises another question: do we even want to keep maintaining it? So there's also option 4:
              1. Make --use-largepages=on a no-op (it can already be a no-op because MADV_HUGEPAGE is only advisory, so the feature only ever works on a best-effort basis), and deprecate it eventually.
              Opening an issue to see if there's any usage of this feature or if there are other ideas to deal with this. If there are real-world users of this feature it may still be worth it to do 2 or 3, but if there are none, we are probably better off deprecating it to cut the maintenance burden (that is not to say to completely say goodbye to work in this line once and for all, but it should be experimented differently other than an opt-in flag that nobody seems to be deploying).
              Activity
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                  None yet
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

                  Skip to content
                  Future of --use-largepages=on #64408
                  Closed
                  #65389
                  Closed
                  Future of --use-largepages=on#64408
                  #65389
                  Labels
                  memoryIssues and PRs related to Node.js memory management or memory footprint.metaIssues and PRs related to the general management of the project.
                  Description
                  @joyeecheung
                  joyeecheung
                  opened on Jul 10, 2026
                  This was added back in 2018, some background can be found in this issue #16198 - from what I can tell we opted into a user-land relocation to work around the fact that for most kernels in the wild, file-backed .text THP won't work out of the box (i.e. CONFIG_READ_ONLY_THP_FOR_FS still isn't on in the mainstream distros most commonly deployed even in 2026, also it is being removed, there are some alternatives though)
                  Currently the --use-largepages implementation incurs two problems:
                  1. It breaks the Node.js binary on WSL1 linux x64 release binary fails to exec on WSL1 #63735
                  2. It will stop working in Node.js after we roll in https://chromium-review.googlesource.com/c/v8/v8/+/7985687
                  2 would be tricky to deal with, it's an optimization that removed the /proc/self/maps parsing overhead and simply rely on address equality of the embedded blob to detect whether it's file-backed, the current method --use-largepages uses to relocate the text region doesn't change the address equality even though the blob is no longer file-backed after relocation, hence it will crash because MREMAP_DONTUNMAP will zero out non-file-backed memory.
                  From what I can think of we have a few choices:
                  1. Convince the upstream to handle the case when the embedded blob is address-equal to the default blob, but is not actually file-backed. From what I can think of this can only be implemented by re-introducing some file parsing overhead (e.g. at least /proc/self/pagemap) to the isolate group initialization process, defeating the optimization added in that CL.
                  2. Add a flag to V8 to enforce checking the blob is file-backed via more robust measures other than address equality, then on the Node.js side, enable that flag when --use-largepages=on
                  3. Reimplement --use-largepages=on by relocating the .text to memory backed by memfd instead of an anonymous memory, then MREMAP_DONTUNMAP won't zero out the memory
                  I think 2 and 3 are probably more viable/have less downsides. But since so far it doesn't look like --use-largepages=on is used a lot in the wild, and the alignment in the build it needs breaks WSL1, it also raises another question: do we even want to keep maintaining it? So there's also option 4:
                  1. Make --use-largepages=on a no-op (it can already be a no-op because MADV_HUGEPAGE is only advisory, so the feature only ever works on a best-effort basis), and deprecate it eventually.
                  Opening an issue to see if there's any usage of this feature or if there are other ideas to deal with this. If there are real-world users of this feature it may still be worth it to do 2 or 3, but if there are none, we are probably better off deprecating it to cut the maintenance burden (that is not to say to completely say goodbye to work in this line once and for all, but it should be experimented differently other than an opt-in flag that nobody seems to be deploying).
                  Activity
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

                      Skip to content
                      Future of --use-largepages=on #64408
                      Closed
                      #65389
                      Closed
                      Future of --use-largepages=on#64408
                      #65389
                      Labels
                      memoryIssues and PRs related to Node.js memory management or memory footprint.metaIssues and PRs related to the general management of the project.
                      Description
                      @joyeecheung
                      joyeecheung
                      opened on Jul 10, 2026
                      This was added back in 2018, some background can be found in this issue #16198 - from what I can tell we opted into a user-land relocation to work around the fact that for most kernels in the wild, file-backed .text THP won't work out of the box (i.e. CONFIG_READ_ONLY_THP_FOR_FS still isn't on in the mainstream distros most commonly deployed even in 2026, also it is being removed, there are some alternatives though)
                      Currently the --use-largepages implementation incurs two problems:
                      1. It breaks the Node.js binary on WSL1 linux x64 release binary fails to exec on WSL1 #63735
                      2. It will stop working in Node.js after we roll in https://chromium-review.googlesource.com/c/v8/v8/+/7985687
                      2 would be tricky to deal with, it's an optimization that removed the /proc/self/maps parsing overhead and simply rely on address equality of the embedded blob to detect whether it's file-backed, the current method --use-largepages uses to relocate the text region doesn't change the address equality even though the blob is no longer file-backed after relocation, hence it will crash because MREMAP_DONTUNMAP will zero out non-file-backed memory.
                      From what I can think of we have a few choices:
                      1. Convince the upstream to handle the case when the embedded blob is address-equal to the default blob, but is not actually file-backed. From what I can think of this can only be implemented by re-introducing some file parsing overhead (e.g. at least /proc/self/pagemap) to the isolate group initialization process, defeating the optimization added in that CL.
                      2. Add a flag to V8 to enforce checking the blob is file-backed via more robust measures other than address equality, then on the Node.js side, enable that flag when --use-largepages=on
                      3. Reimplement --use-largepages=on by relocating the .text to memory backed by memfd instead of an anonymous memory, then MREMAP_DONTUNMAP won't zero out the memory
                      I think 2 and 3 are probably more viable/have less downsides. But since so far it doesn't look like --use-largepages=on is used a lot in the wild, and the alignment in the build it needs breaks WSL1, it also raises another question: do we even want to keep maintaining it? So there's also option 4:
                      1. Make --use-largepages=on a no-op (it can already be a no-op because MADV_HUGEPAGE is only advisory, so the feature only ever works on a best-effort basis), and deprecate it eventually.
                      Opening an issue to see if there's any usage of this feature or if there are other ideas to deal with this. If there are real-world users of this feature it may still be worth it to do 2 or 3, but if there are none, we are probably better off deprecating it to cut the maintenance burden (that is not to say to completely say goodbye to work in this line once and for all, but it should be experimented differently other than an opt-in flag that nobody seems to be deploying).
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

                          Skip to content
                          Future of --use-largepages=on #64408
                          Closed
                          #65389
                          Closed
                          Future of --use-largepages=on#64408
                          #65389
                          Labels
                          memoryIssues and PRs related to Node.js memory management or memory footprint.metaIssues and PRs related to the general management of the project.
                          Description
                          @joyeecheung
                          joyeecheung
                          opened on Jul 10, 2026
                          This was added back in 2018, some background can be found in this issue #16198 - from what I can tell we opted into a user-land relocation to work around the fact that for most kernels in the wild, file-backed .text THP won't work out of the box (i.e. CONFIG_READ_ONLY_THP_FOR_FS still isn't on in the mainstream distros most commonly deployed even in 2026, also it is being removed, there are some alternatives though)
                          Currently the --use-largepages implementation incurs two problems:
                          1. It breaks the Node.js binary on WSL1 linux x64 release binary fails to exec on WSL1 #63735
                          2. It will stop working in Node.js after we roll in https://chromium-review.googlesource.com/c/v8/v8/+/7985687
                          2 would be tricky to deal with, it's an optimization that removed the /proc/self/maps parsing overhead and simply rely on address equality of the embedded blob to detect whether it's file-backed, the current method --use-largepages uses to relocate the text region doesn't change the address equality even though the blob is no longer file-backed after relocation, hence it will crash because MREMAP_DONTUNMAP will zero out non-file-backed memory.
                          From what I can think of we have a few choices:
                          1. Convince the upstream to handle the case when the embedded blob is address-equal to the default blob, but is not actually file-backed. From what I can think of this can only be implemented by re-introducing some file parsing overhead (e.g. at least /proc/self/pagemap) to the isolate group initialization process, defeating the optimization added in that CL.
                          2. Add a flag to V8 to enforce checking the blob is file-backed via more robust measures other than address equality, then on the Node.js side, enable that flag when --use-largepages=on
                          3. Reimplement --use-largepages=on by relocating the .text to memory backed by memfd instead of an anonymous memory, then MREMAP_DONTUNMAP won't zero out the memory
                          I think 2 and 3 are probably more viable/have less downsides. But since so far it doesn't look like --use-largepages=on is used a lot in the wild, and the alignment in the build it needs breaks WSL1, it also raises another question: do we even want to keep maintaining it? So there's also option 4:
                          1. Make --use-largepages=on a no-op (it can already be a no-op because MADV_HUGEPAGE is only advisory, so the feature only ever works on a best-effort basis), and deprecate it eventually.
                          Opening an issue to see if there's any usage of this feature or if there are other ideas to deal with this. If there are real-world users of this feature it may still be worth it to do 2 or 3, but if there are none, we are probably better off deprecating it to cut the maintenance burden (that is not to say to completely say goodbye to work in this line once and for all, but it should be experimented differently other than an opt-in flag that nobody seems to be deploying).
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

                              Skip to content
                              Future of --use-largepages=on #64408
                              Closed
                              #65389
                              Closed
                              Future of --use-largepages=on#64408
                              #65389
                              Labels
                              memoryIssues and PRs related to Node.js memory management or memory footprint.metaIssues and PRs related to the general management of the project.
                              Description
                              @joyeecheung
                              joyeecheung
                              opened on Jul 10, 2026
                              This was added back in 2018, some background can be found in this issue #16198 - from what I can tell we opted into a user-land relocation to work around the fact that for most kernels in the wild, file-backed .text THP won't work out of the box (i.e. CONFIG_READ_ONLY_THP_FOR_FS still isn't on in the mainstream distros most commonly deployed even in 2026, also it is being removed, there are some alternatives though)
                              Currently the --use-largepages implementation incurs two problems:
                              1. It breaks the Node.js binary on WSL1 linux x64 release binary fails to exec on WSL1 #63735
                              2. It will stop working in Node.js after we roll in https://chromium-review.googlesource.com/c/v8/v8/+/7985687
                              2 would be tricky to deal with, it's an optimization that removed the /proc/self/maps parsing overhead and simply rely on address equality of the embedded blob to detect whether it's file-backed, the current method --use-largepages uses to relocate the text region doesn't change the address equality even though the blob is no longer file-backed after relocation, hence it will crash because MREMAP_DONTUNMAP will zero out non-file-backed memory.
                              From what I can think of we have a few choices:
                              1. Convince the upstream to handle the case when the embedded blob is address-equal to the default blob, but is not actually file-backed. From what I can think of this can only be implemented by re-introducing some file parsing overhead (e.g. at least /proc/self/pagemap) to the isolate group initialization process, defeating the optimization added in that CL.
                              2. Add a flag to V8 to enforce checking the blob is file-backed via more robust measures other than address equality, then on the Node.js side, enable that flag when --use-largepages=on
                              3. Reimplement --use-largepages=on by relocating the .text to memory backed by memfd instead of an anonymous memory, then MREMAP_DONTUNMAP won't zero out the memory
                              I think 2 and 3 are probably more viable/have less downsides. But since so far it doesn't look like --use-largepages=on is used a lot in the wild, and the alignment in the build it needs breaks WSL1, it also raises another question: do we even want to keep maintaining it? So there's also option 4:
                              1. Make --use-largepages=on a no-op (it can already be a no-op because MADV_HUGEPAGE is only advisory, so the feature only ever works on a best-effort basis), and deprecate it eventually.
                              Opening an issue to see if there's any usage of this feature or if there are other ideas to deal with this. If there are real-world users of this feature it may still be worth it to do 2 or 3, but if there are none, we are probably better off deprecating it to cut the maintenance burden (that is not to say to completely say goodbye to work in this line once and for all, but it should be experimented differently other than an opt-in flag that nobody seems to be deploying).
                              Activity
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