VirtualShip v1 / Parcels v4 performance #357

Open
Open
VirtualShip v1 / Parcels v4 performance#357

Description

@j-atkins
j-atkins
opened on Jul 16, 2026

Summary

This issue is to acknowledge and track the progress of Parcels v4 performance with copernicusmarine (see #2756) and its relevance to VirtualShip v1.

More detail

A core part of an upcoming VirtualShip v1 release (#195) will mean the move from Parcels v3 -> v4 (#342) under the hood. In line with the aims of the Parcels v4 release, this overhauls the VirtualShip internals to align more closely with the Pangeo ecosystem and use vectorised operations.

Parcels v4 computation works and is ready for use in VirtualShip simulations, but its performance will continue to be improved as v4 evolves. Latest performance testing suggests that local data ingestion is performant but streaming workflows (e.g. with copernicusmarine) are slower. This is relevant to VirtualShip, where a key feature is the default Digital Twin/streaming nature of the framework. Thus, we should expect to see some performance decrease on initial VirtualShip v1 release. However, ongoing work on the Parcels side to increase performance in v4.x... will feed directly into VirtualShip.

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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
      VirtualShip v1 / Parcels v4 performance #357
      Open
      Open
      VirtualShip v1 / Parcels v4 performance#357
      Description
      @j-atkins
      j-atkins
      opened on Jul 16, 2026
      Summary
      This issue is to acknowledge and track the progress of Parcels v4 performance with copernicusmarine (see #2756) and its relevance to VirtualShip v1.
      More detail
      A core part of an upcoming VirtualShip v1 release (#195) will mean the move from Parcels v3 -> v4 (#342) under the hood. In line with the aims of the Parcels v4 release, this overhauls the VirtualShip internals to align more closely with the Pangeo ecosystem and use vectorised operations.
      Parcels v4 computation works and is ready for use in VirtualShip simulations, but its performance will continue to be improved as v4 evolves. Latest performance testing suggests that local data ingestion is performant but streaming workflows (e.g. with copernicusmarine) are slower. This is relevant to VirtualShip, where a key feature is the default Digital Twin/streaming nature of the framework. Thus, we should expect to see some performance decrease on initial VirtualShip v1 release. However, ongoing work on the Parcels side to increase performance in v4.x... will feed directly into VirtualShip.
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          No branches or pull requests
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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
          VirtualShip v1 / Parcels v4 performance #357
          Open
          Open
          VirtualShip v1 / Parcels v4 performance#357
          Description
          @j-atkins
          j-atkins
          opened on Jul 16, 2026
          Summary
          This issue is to acknowledge and track the progress of Parcels v4 performance with copernicusmarine (see #2756) and its relevance to VirtualShip v1.
          More detail
          A core part of an upcoming VirtualShip v1 release (#195) will mean the move from Parcels v3 -> v4 (#342) under the hood. In line with the aims of the Parcels v4 release, this overhauls the VirtualShip internals to align more closely with the Pangeo ecosystem and use vectorised operations.
          Parcels v4 computation works and is ready for use in VirtualShip simulations, but its performance will continue to be improved as v4 evolves. Latest performance testing suggests that local data ingestion is performant but streaming workflows (e.g. with copernicusmarine) are slower. This is relevant to VirtualShip, where a key feature is the default Digital Twin/streaming nature of the framework. Thus, we should expect to see some performance decrease on initial VirtualShip v1 release. However, ongoing work on the Parcels side to increase performance in v4.x... will feed directly into VirtualShip.
          Metadata
          Metadata
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          No one assigned
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            No labels
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            No type
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              No milestone
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              None yet
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              No branches or pull requests
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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
              VirtualShip v1 / Parcels v4 performance #357
              Open
              Open
              VirtualShip v1 / Parcels v4 performance#357
              Description
              @j-atkins
              j-atkins
              opened on Jul 16, 2026
              Summary
              This issue is to acknowledge and track the progress of Parcels v4 performance with copernicusmarine (see #2756) and its relevance to VirtualShip v1.
              More detail
              A core part of an upcoming VirtualShip v1 release (#195) will mean the move from Parcels v3 -> v4 (#342) under the hood. In line with the aims of the Parcels v4 release, this overhauls the VirtualShip internals to align more closely with the Pangeo ecosystem and use vectorised operations.
              Parcels v4 computation works and is ready for use in VirtualShip simulations, but its performance will continue to be improved as v4 evolves. Latest performance testing suggests that local data ingestion is performant but streaming workflows (e.g. with copernicusmarine) are slower. This is relevant to VirtualShip, where a key feature is the default Digital Twin/streaming nature of the framework. Thus, we should expect to see some performance decrease on initial VirtualShip v1 release. However, ongoing work on the Parcels side to increase performance in v4.x... will feed directly into VirtualShip.
              Metadata
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              No one assigned
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                  None yet
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                  No branches or pull requests
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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
                  VirtualShip v1 / Parcels v4 performance #357
                  Open
                  Open
                  VirtualShip v1 / Parcels v4 performance#357
                  Description
                  @j-atkins
                  j-atkins
                  opened on Jul 16, 2026
                  Summary
                  This issue is to acknowledge and track the progress of Parcels v4 performance with copernicusmarine (see #2756) and its relevance to VirtualShip v1.
                  More detail
                  A core part of an upcoming VirtualShip v1 release (#195) will mean the move from Parcels v3 -> v4 (#342) under the hood. In line with the aims of the Parcels v4 release, this overhauls the VirtualShip internals to align more closely with the Pangeo ecosystem and use vectorised operations.
                  Parcels v4 computation works and is ready for use in VirtualShip simulations, but its performance will continue to be improved as v4 evolves. Latest performance testing suggests that local data ingestion is performant but streaming workflows (e.g. with copernicusmarine) are slower. This is relevant to VirtualShip, where a key feature is the default Digital Twin/streaming nature of the framework. Thus, we should expect to see some performance decrease on initial VirtualShip v1 release. However, ongoing work on the Parcels side to increase performance in v4.x... will feed directly into VirtualShip.
                  Metadata
                  Metadata
                  Assignees
                  No one assigned
                    Labels
                    No labels
                    No labels
                    Type
                    No type
                    Projects
                    No 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
                      VirtualShip v1 / Parcels v4 performance #357
                      Open
                      Open
                      VirtualShip v1 / Parcels v4 performance#357
                      Description
                      @j-atkins
                      j-atkins
                      opened on Jul 16, 2026
                      Summary
                      This issue is to acknowledge and track the progress of Parcels v4 performance with copernicusmarine (see #2756) and its relevance to VirtualShip v1.
                      More detail
                      A core part of an upcoming VirtualShip v1 release (#195) will mean the move from Parcels v3 -> v4 (#342) under the hood. In line with the aims of the Parcels v4 release, this overhauls the VirtualShip internals to align more closely with the Pangeo ecosystem and use vectorised operations.
                      Parcels v4 computation works and is ready for use in VirtualShip simulations, but its performance will continue to be improved as v4 evolves. Latest performance testing suggests that local data ingestion is performant but streaming workflows (e.g. with copernicusmarine) are slower. This is relevant to VirtualShip, where a key feature is the default Digital Twin/streaming nature of the framework. Thus, we should expect to see some performance decrease on initial VirtualShip v1 release. However, ongoing work on the Parcels side to increase performance in v4.x... will feed directly into VirtualShip.
                      Metadata
                      Metadata
                      Assignees
                      No one assigned
                        Labels
                        No labels
                        No labels
                        Type
                        No type
                        Projects
                        No 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
                          VirtualShip v1 / Parcels v4 performance #357
                          Open
                          Open
                          VirtualShip v1 / Parcels v4 performance#357
                          Description
                          @j-atkins
                          j-atkins
                          opened on Jul 16, 2026
                          Summary
                          This issue is to acknowledge and track the progress of Parcels v4 performance with copernicusmarine (see #2756) and its relevance to VirtualShip v1.
                          More detail
                          A core part of an upcoming VirtualShip v1 release (#195) will mean the move from Parcels v3 -> v4 (#342) under the hood. In line with the aims of the Parcels v4 release, this overhauls the VirtualShip internals to align more closely with the Pangeo ecosystem and use vectorised operations.
                          Parcels v4 computation works and is ready for use in VirtualShip simulations, but its performance will continue to be improved as v4 evolves. Latest performance testing suggests that local data ingestion is performant but streaming workflows (e.g. with copernicusmarine) are slower. This is relevant to VirtualShip, where a key feature is the default Digital Twin/streaming nature of the framework. Thus, we should expect to see some performance decrease on initial VirtualShip v1 release. However, ongoing work on the Parcels side to increase performance in v4.x... will feed directly into VirtualShip.
                          Metadata
                          Metadata
                          Assignees
                          No one assigned
                            Labels
                            No labels
                            No labels
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                            No type
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                            No 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
                              VirtualShip v1 / Parcels v4 performance #357
                              Open
                              Open
                              VirtualShip v1 / Parcels v4 performance#357
                              Description
                              @j-atkins
                              j-atkins
                              opened on Jul 16, 2026
                              Summary
                              This issue is to acknowledge and track the progress of Parcels v4 performance with copernicusmarine (see #2756) and its relevance to VirtualShip v1.
                              More detail
                              A core part of an upcoming VirtualShip v1 release (#195) will mean the move from Parcels v3 -> v4 (#342) under the hood. In line with the aims of the Parcels v4 release, this overhauls the VirtualShip internals to align more closely with the Pangeo ecosystem and use vectorised operations.
                              Parcels v4 computation works and is ready for use in VirtualShip simulations, but its performance will continue to be improved as v4 evolves. Latest performance testing suggests that local data ingestion is performant but streaming workflows (e.g. with copernicusmarine) are slower. This is relevant to VirtualShip, where a key feature is the default Digital Twin/streaming nature of the framework. Thus, we should expect to see some performance decrease on initial VirtualShip v1 release. However, ongoing work on the Parcels side to increase performance in v4.x... will feed directly into VirtualShip.
                              Metadata
                              Metadata
                              Assignees
                              No one assigned
                                Labels
                                No labels
                                No labels
                                Type
                                No type
                                Projects
                                No projects
                                  Milestone
                                  No milestone
                                  Relationships
                                  None yet
                                  Development
                                  No branches or pull requests
                                  Issue actions