Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read #64

Closed
#65
Closed
Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read#64
#65
Labels
bugSomething isn't working

Description

@borlandong
borlandong
opened on Jan 22, 2026

Describe the bug
The function _lx_nand_flash_sector_read has a serious performance issue. The current implementation reads both the main data area and spare data area of the entire page when matching logical sector numbers, which is unnecessary and causes significant performance degradation.

Environment

  • Arm Cortex M7
  • ThreadX 6.4.1
  • arm-gnu-toolchain-13.3
  • Device: W25N01GV NAND Flash
  • Stack: LevelX + FileX
  • Test file size: 680KB

Problem Analysis
During the logical sector number matching process, we only need to read the spare area data. Reading the main data area at this stage is completely unnecessary and severely impacts performance.

Performance Impact
I implemented LevelX + FileX on W25N01GV and measured the following performance:

Before fix:

  • Write 680KB file: 2258 ms
  • Read 680KB file: 10954 ms

After fix:

  • Write 680KB file: 1757 ms
  • Read 680KB file: 3113 ms

Improvement:

  • Write performance: ~22% faster
  • Read performance: ~3.5x faster (252% improvement)

The read performance improvement is particularly significant, making this fix essential.

Proposed Solution
Optimize _lx_nand_flash_sector_read to read only the spare area during logical sector matching. The NAND flash driver should check if the main data area pointer is NULL and skip reading the main data area accordingly.

Additional context
I have already prepared a fix for this issue and will submit a PR shortly.

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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
    Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read #64
    Closed
    #65
    Closed
    Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read#64
    #65
    Labels
    bugSomething isn't working
    Description
    @borlandong
    borlandong
    opened on Jan 22, 2026
    Describe the bug
    
The function _lx_nand_flash_sector_read has a serious performance issue. The current implementation reads both the main data area and spare data area of the entire page when matching logical sector numbers, which is unnecessary and causes significant performance degradation.
    Environment
    • Arm Cortex M7
    • ThreadX 6.4.1
    • arm-gnu-toolchain-13.3
    • Device: W25N01GV NAND Flash
    • Stack: LevelX + FileX
    • Test file size: 680KB
    Problem Analysis
    
During the logical sector number matching process, we only need to read the spare area data. Reading the main data area at this stage is completely unnecessary and severely impacts performance.
    Performance Impact
    
I implemented LevelX + FileX on W25N01GV and measured the following performance:
    Before fix:
    • Write 680KB file: 2258 ms
    • Read 680KB file: 10954 ms
    After fix:
    • Write 680KB file: 1757 ms
    • Read 680KB file: 3113 ms
    Improvement:
    • Write performance: ~22% faster
    • Read performance: ~3.5x faster (252% improvement)
    The read performance improvement is particularly significant, making this fix essential.
    Proposed Solution
    
Optimize _lx_nand_flash_sector_read to read only the spare area during logical sector matching. The NAND flash driver should check if the main data area pointer is NULL and skip reading the main data area accordingly.
    Additional context
    
I have already prepared a fix for this issue and will submit a PR shortly.
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      bugSomething isn't working
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      None yet
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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
      Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read #64
      Closed
      #65
      Closed
      Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read#64
      #65
      Labels
      bugSomething isn't working
      Description
      @borlandong
      borlandong
      opened on Jan 22, 2026
      Describe the bug
      
The function _lx_nand_flash_sector_read has a serious performance issue. The current implementation reads both the main data area and spare data area of the entire page when matching logical sector numbers, which is unnecessary and causes significant performance degradation.
      Environment
      • Arm Cortex M7
      • ThreadX 6.4.1
      • arm-gnu-toolchain-13.3
      • Device: W25N01GV NAND Flash
      • Stack: LevelX + FileX
      • Test file size: 680KB
      Problem Analysis
      
During the logical sector number matching process, we only need to read the spare area data. Reading the main data area at this stage is completely unnecessary and severely impacts performance.
      Performance Impact
      
I implemented LevelX + FileX on W25N01GV and measured the following performance:
      Before fix:
      • Write 680KB file: 2258 ms
      • Read 680KB file: 10954 ms
      After fix:
      • Write 680KB file: 1757 ms
      • Read 680KB file: 3113 ms
      Improvement:
      • Write performance: ~22% faster
      • Read performance: ~3.5x faster (252% improvement)
      The read performance improvement is particularly significant, making this fix essential.
      Proposed Solution
      
Optimize _lx_nand_flash_sector_read to read only the spare area during logical sector matching. The NAND flash driver should check if the main data area pointer is NULL and skip reading the main data area accordingly.
      Additional context
      
I have already prepared a fix for this issue and will submit a PR shortly.
      Metadata
      Metadata
      Assignees
      No one assigned
        Labels
        bugSomething isn't working
        Type
        No type
        Projects
        Milestone
        No milestone
        Relationships
        None yet
        Development
        No branches or pull requests
        Issue actions
        
, '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
        Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read #64
        Closed
        #65
        Closed
        Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read#64
        #65
        Labels
        bugSomething isn't working
        Description
        @borlandong
        borlandong
        opened on Jan 22, 2026
        Describe the bug
        
The function _lx_nand_flash_sector_read has a serious performance issue. The current implementation reads both the main data area and spare data area of the entire page when matching logical sector numbers, which is unnecessary and causes significant performance degradation.
        Environment
        • Arm Cortex M7
        • ThreadX 6.4.1
        • arm-gnu-toolchain-13.3
        • Device: W25N01GV NAND Flash
        • Stack: LevelX + FileX
        • Test file size: 680KB
        Problem Analysis
        
During the logical sector number matching process, we only need to read the spare area data. Reading the main data area at this stage is completely unnecessary and severely impacts performance.
        Performance Impact
        
I implemented LevelX + FileX on W25N01GV and measured the following performance:
        Before fix:
        • Write 680KB file: 2258 ms
        • Read 680KB file: 10954 ms
        After fix:
        • Write 680KB file: 1757 ms
        • Read 680KB file: 3113 ms
        Improvement:
        • Write performance: ~22% faster
        • Read performance: ~3.5x faster (252% improvement)
        The read performance improvement is particularly significant, making this fix essential.
        Proposed Solution
        
Optimize _lx_nand_flash_sector_read to read only the spare area during logical sector matching. The NAND flash driver should check if the main data area pointer is NULL and skip reading the main data area accordingly.
        Additional context
        
I have already prepared a fix for this issue and will submit a PR shortly.
        Metadata
        Metadata
        Assignees
        No one assigned
          Labels
          bugSomething isn't working
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          No type
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          Milestone
          No milestone
          Relationships
          None yet
          Development
          No branches or pull requests
          Issue actions
          
, '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
          Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read #64
          Closed
          #65
          Closed
          Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read#64
          #65
          Labels
          bugSomething isn't working
          Description
          @borlandong
          borlandong
          opened on Jan 22, 2026
          Describe the bug
          
The function _lx_nand_flash_sector_read has a serious performance issue. The current implementation reads both the main data area and spare data area of the entire page when matching logical sector numbers, which is unnecessary and causes significant performance degradation.
          Environment
          • Arm Cortex M7
          • ThreadX 6.4.1
          • arm-gnu-toolchain-13.3
          • Device: W25N01GV NAND Flash
          • Stack: LevelX + FileX
          • Test file size: 680KB
          Problem Analysis
          
During the logical sector number matching process, we only need to read the spare area data. Reading the main data area at this stage is completely unnecessary and severely impacts performance.
          Performance Impact
          
I implemented LevelX + FileX on W25N01GV and measured the following performance:
          Before fix:
          • Write 680KB file: 2258 ms
          • Read 680KB file: 10954 ms
          After fix:
          • Write 680KB file: 1757 ms
          • Read 680KB file: 3113 ms
          Improvement:
          • Write performance: ~22% faster
          • Read performance: ~3.5x faster (252% improvement)
          The read performance improvement is particularly significant, making this fix essential.
          Proposed Solution
          
Optimize _lx_nand_flash_sector_read to read only the spare area during logical sector matching. The NAND flash driver should check if the main data area pointer is NULL and skip reading the main data area accordingly.
          Additional context
          
I have already prepared a fix for this issue and will submit a PR shortly.
          Metadata
          Metadata
          Assignees
          No one assigned
            Labels
            bugSomething isn't working
            Type
            No type
            Projects
            Milestone
            No milestone
            Relationships
            None yet
            Development
            No branches or pull requests
            Issue actions
            
, '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
            Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read #64
            Closed
            #65
            Closed
            Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read#64
            #65
            Labels
            bugSomething isn't working
            Description
            @borlandong
            borlandong
            opened on Jan 22, 2026
            Describe the bug
            
The function _lx_nand_flash_sector_read has a serious performance issue. The current implementation reads both the main data area and spare data area of the entire page when matching logical sector numbers, which is unnecessary and causes significant performance degradation.
            Environment
            • Arm Cortex M7
            • ThreadX 6.4.1
            • arm-gnu-toolchain-13.3
            • Device: W25N01GV NAND Flash
            • Stack: LevelX + FileX
            • Test file size: 680KB
            Problem Analysis
            
During the logical sector number matching process, we only need to read the spare area data. Reading the main data area at this stage is completely unnecessary and severely impacts performance.
            Performance Impact
            
I implemented LevelX + FileX on W25N01GV and measured the following performance:
            Before fix:
            • Write 680KB file: 2258 ms
            • Read 680KB file: 10954 ms
            After fix:
            • Write 680KB file: 1757 ms
            • Read 680KB file: 3113 ms
            Improvement:
            • Write performance: ~22% faster
            • Read performance: ~3.5x faster (252% improvement)
            The read performance improvement is particularly significant, making this fix essential.
            Proposed Solution
            
Optimize _lx_nand_flash_sector_read to read only the spare area during logical sector matching. The NAND flash driver should check if the main data area pointer is NULL and skip reading the main data area accordingly.
            Additional context
            
I have already prepared a fix for this issue and will submit a PR shortly.
            Metadata
            Metadata
            Assignees
            No one assigned
              Labels
              bugSomething isn't working
              Type
              No type
              Projects
              Milestone
              No milestone
              Relationships
              None yet
              Development
              No branches or pull requests
              Issue actions
              
, '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
              Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read #64
              Closed
              #65
              Closed
              Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read#64
              #65
              Labels
              bugSomething isn't working
              Description
              @borlandong
              borlandong
              opened on Jan 22, 2026
              Describe the bug
              
The function _lx_nand_flash_sector_read has a serious performance issue. The current implementation reads both the main data area and spare data area of the entire page when matching logical sector numbers, which is unnecessary and causes significant performance degradation.
              Environment
              • Arm Cortex M7
              • ThreadX 6.4.1
              • arm-gnu-toolchain-13.3
              • Device: W25N01GV NAND Flash
              • Stack: LevelX + FileX
              • Test file size: 680KB
              Problem Analysis
              
During the logical sector number matching process, we only need to read the spare area data. Reading the main data area at this stage is completely unnecessary and severely impacts performance.
              Performance Impact
              
I implemented LevelX + FileX on W25N01GV and measured the following performance:
              Before fix:
              • Write 680KB file: 2258 ms
              • Read 680KB file: 10954 ms
              After fix:
              • Write 680KB file: 1757 ms
              • Read 680KB file: 3113 ms
              Improvement:
              • Write performance: ~22% faster
              • Read performance: ~3.5x faster (252% improvement)
              The read performance improvement is particularly significant, making this fix essential.
              Proposed Solution
              
Optimize _lx_nand_flash_sector_read to read only the spare area during logical sector matching. The NAND flash driver should check if the main data area pointer is NULL and skip reading the main data area accordingly.
              Additional context
              
I have already prepared a fix for this issue and will submit a PR shortly.
              Metadata
              Metadata
              Assignees
              No one assigned
                Labels
                bugSomething isn't working
                Type
                No type
                Projects
                Milestone
                No milestone
                Relationships
                None yet
                Development
                No branches or pull requests
                Issue actions
                
, '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
                Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read #64
                Closed
                #65
                Closed
                Performance Issue: Unnecessary main data area read in _lx_nand_flash_sector_read#64
                #65
                Labels
                bugSomething isn't working
                Description
                @borlandong
                borlandong
                opened on Jan 22, 2026
                Describe the bug
                
The function _lx_nand_flash_sector_read has a serious performance issue. The current implementation reads both the main data area and spare data area of the entire page when matching logical sector numbers, which is unnecessary and causes significant performance degradation.
                Environment
                • Arm Cortex M7
                • ThreadX 6.4.1
                • arm-gnu-toolchain-13.3
                • Device: W25N01GV NAND Flash
                • Stack: LevelX + FileX
                • Test file size: 680KB
                Problem Analysis
                
During the logical sector number matching process, we only need to read the spare area data. Reading the main data area at this stage is completely unnecessary and severely impacts performance.
                Performance Impact
                
I implemented LevelX + FileX on W25N01GV and measured the following performance:
                Before fix:
                • Write 680KB file: 2258 ms
                • Read 680KB file: 10954 ms
                After fix:
                • Write 680KB file: 1757 ms
                • Read 680KB file: 3113 ms
                Improvement:
                • Write performance: ~22% faster
                • Read performance: ~3.5x faster (252% improvement)
                The read performance improvement is particularly significant, making this fix essential.
                Proposed Solution
                
Optimize _lx_nand_flash_sector_read to read only the spare area during logical sector matching. The NAND flash driver should check if the main data area pointer is NULL and skip reading the main data area accordingly.
                Additional context
                
I have already prepared a fix for this issue and will submit a PR shortly.
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