{"id":24245,"date":"2021-09-13T14:40:29","date_gmt":"2021-09-13T13:40:29","guid":{"rendered":"https:\/\/www.ch.imperial.ac.uk\/rzepa\/blog\/?p=24245"},"modified":"2022-02-11T08:39:17","modified_gmt":"2022-02-11T08:39:17","slug":"computational-hybrid-access-and-metadata-portal-champ","status":"publish","type":"post","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=24245","title":{"rendered":"HPC Access and Metadata Portal (CHAMP)."},"content":{"rendered":"<div class=\"kcite-section\" kcite-section-id=\"24245\">\n<p>You might have noticed if you have read any of my posts here is that many of them have been accompanied since 2006 by supporting calculations, normally based on density functional theory (DFT) and these calculations are accompanied by a persistent identifier pointer<sup>\u2021<\/sup> to a data repository publication. I have hitherto not gone into the detail here of the infrastructures required to do this sort of thing, but recently one of the two components has been updated to V2, after being at\u00a0V1 for some fourteen years<span id=\"cite_ITEM-24245-0\" name=\"citation\"><a href=\"#ITEM-24245-0\">[1]<\/a><\/span> \u00a0and this provides a timely opportunity to describe the system a little more.\u00a0<\/p>\n<p>The original design was based on what we called a portal to access the high performance computing (HPC) resources available centrally. These are controlled by a commercial package called <a href=\"https:\/\/www.altair.com\/pbs-professional\/\">PBS<\/a>\u00a0which provides a command line driven interface to batch queues. Whilst powerful, PBS can also be complex, and for every day routine use it seemed more convenient to package up this interface into a Web-accessed portal which also included the ability to specify the resources needed (such as memory, number of CPUs, etc) to run the desired compute program, in our case the Gaussian 16 package and to complete things by adding a simple interface to a data repository for use when the calculation was completed.<\/p>\n<p><a href=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-833-scaled.jpg\"><img decoding=\"async\" class=\"aligncenter size-large wp-image-24248\" src=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-833-1024x341.jpg\" alt=\"\" width=\"550\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-833-1024x341.jpg 1024w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-833-300x100.jpg 300w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-833-768x255.jpg 768w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-833-1536x511.jpg 1536w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-833-2048x681.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/a><\/p>\n<p>The process of using this tool, which functions in essence as an Electronic Laboratory Notebook or ELN for computational chemistry, can be summarised as a workflow, which occurs horizontally in the screenshot of V1 above. Each job is assigned an internal ID, which is associated with a pre-configured project and given a searchable description. Its status in the PBS-controlled queues is indicated and when finished the associated input and output files become available for download, with an option to delete these if they are not in fact needed, and a final option to publish to the accompanying tool which is a data repository. V1 of this portal was in fact written in the PHP scripting language and controlled behind the scenes using a MySQL database, which allows the entries to be filtered by search terms such as the assigned project or the description. This proved particularly useful when the number of entries reached large numbers (&gt; 100,000 eventually) and meant that even 15-year old entries could be easily found and inspected!<\/p>\n<p>Although this workflow proved highly robust, the underlying PHP system and associated code became increasingly unmaintainable and in 2021 we decided to refactor it for greater sustainability. We had noticed that in 2018, another group had taken the basic concept we had used in 2006, written a more flexible and portable opensource toolkit for building such a portal, calling it Open OnDemand: A Web-based client portal for HPC centers and published a description.<span id=\"cite_ITEM-24245-1\" name=\"citation\"><a href=\"#ITEM-24245-1\">[2]<\/a><\/span> In effect, a lot of the work in maintenance is now divested to a separate group and accordingly our software engineering group here at Imperial were far happier using such a tool. So now enter V2 of our own portal, which we now call HPC Access and Metadata Portal or <strong>CHAMP<\/strong>.<span id=\"cite_ITEM-24245-2\" name=\"citation\"><a href=\"#ITEM-24245-2\">[3]<\/a><\/span><\/p>\n<p><a href=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-835.jpg\"><img decoding=\"async\" class=\"aligncenter size-large wp-image-24253\" src=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-835-1024x527.jpg\" alt=\"\" width=\"550\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-835-1024x527.jpg 1024w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-835-300x154.jpg 300w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-835-768x395.jpg 768w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-835-1536x790.jpg 1536w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-835-2048x1054.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/a><\/p>\n<p>The workflow is very much the same as before, but with added flexibility that allows custom resources to be selected which might include eg special grant-funded priority queues. Additionally, a new directory tool allows inspection of any job inputs or outputs, provided by the Open OnDemand package and which greatly facilitates minute-to-minute management\/inspection of jobs to ensure the outputs are those expected for a properly functioning job.<\/p>\n<p><a href=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-836.jpg\"><img decoding=\"async\" class=\"aligncenter size-large wp-image-24255\" src=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-836-1024x913.jpg\" alt=\"\" width=\"550\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-836-1024x913.jpg 1024w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-836-300x267.jpg 300w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-836-768x685.jpg 768w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-836.jpg 1380w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/a><\/p>\n<p>If the job is deemed suitable for sharing, the publish button is pressed. This induces a workflow which, <em>inter alia<\/em>, converts the system specific checkpoint file to an formatted version which can be used on any system and generates a number of extra files needed for publication of the job.<\/p>\n<p><a href=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-837.jpg\"><img decoding=\"async\" class=\"aligncenter size-large wp-image-24259\" src=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-837-865x1024.jpg\" alt=\"\" width=\"550\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-837-865x1024.jpg 865w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-837-253x300.jpg 253w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-837-768x909.jpg 768w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-837-1297x1536.jpg 1297w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-837.jpg 1390w\" sizes=\"(max-width: 865px) 100vw, 865px\" \/><\/a><\/p>\n<p>Also of interest is the METADATA file, which generates calculation-specific metadata suitable for injection into the data repository. Currently, this includes the InChI string and Key for the molecule calculated and the Gibbs_Energy, the purpose of which was described in <a href=\"https:\/\/www.ch.imperial.ac.uk\/rzepa\/blog\/?p=19892\" target=\"_blank\" rel=\"noopener\">this post<\/a>. In the future we plan to make this metadata even richer with further information. This calculation-specific metadata will later be conflated with generic metadata for the final publication on the actual repository. That full metadata record includes information about the person who ran the job (their ORCID etc), the institution they are at, the data licensing etc., garnered in part from the profile entry for that user on the CHAMP portal.<\/p>\n<p><a href=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-large wp-image-24278\" src=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838-1024x923.jpg\" alt=\"\" width=\"450\" height=\"406\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838-1024x923.jpg 1024w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838-300x270.jpg 300w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838-768x692.jpg 768w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838.jpg 1434w\" sizes=\"auto, (max-width: 450px) 100vw, 450px\" \/><\/a><\/p>\n<p>After publication, the CHAMP entry for the job is updated to include the DOI for the data publication, and hyperlinked to allow immediate access to this entry in the repository.<\/p>\n<p><a href=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-839.jpg\"><img decoding=\"async\" class=\"aligncenter size-large wp-image-24262\" src=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/published.jpg\" alt=\"\" width=\"540\" \/><\/a><\/p>\n<p>An information page about the job also includes a link to the final full published metadata record(s).<a href=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/published.jpg\"><br \/>\n<\/a> <a href=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838-1.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-large wp-image-24281\" src=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838-1-1024x797.jpg\" alt=\"\" width=\"450\" height=\"350\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838-1-1024x797.jpg 1024w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838-1-300x233.jpg 300w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838-1-768x597.jpg 768w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-838-1.jpg 1414w\" sizes=\"auto, (max-width: 450px) 100vw, 450px\" \/><\/a><\/p>\n<p>CHAMP currently includes workflows to publish to the Imperial College repository. Zenodo has also now been added and possibly other repositories in the future as demand requires.<\/p>\n<p>You can see here \u00a0that \u00a0I have described how an \u00a0ELN was originally designed from scratch to control quantum calculations, and how an essential symbiotic partner to this resource was considered to be a data repository at the outset, even way back in 2006. \u00a0Now, the first of these resources has been refactored into modern form and no doubt the repository end will also be in the future. The code is available for anyone to create a similar compute portal for themselves.<\/p>\n<p>A different version of this description, including more details of the software engineering, will shortly be submitted to the\u00a0<a href=\"https:\/\/joss.theoj.org\/\">Journal of Open Source Software<\/a>, along with source code suitable for use with Open OnDemand at <a href=\"https:\/\/github.com\/ImperialCollegeLondon\/hpc_portal\/\">https:\/\/github.com\/ImperialCollegeLondon\/hpc_portal\/<\/a>.<\/p>\n<hr \/>\n<p><sup>\u2021<\/sup> Originally in the form of a Handle, which was replaced by the use of a DOI. The DOI for this post itself is <a href=\"https:\/\/doi.org\/10.14469\/hpc\/9010\">10.14469\/hpc\/9010<\/a><\/p>\n<h2>References<\/h2>\n    <ol class=\"kcite-bibliography csl-bib-body\"><li id=\"ITEM-24245-0\">M.J. Harvey, N.J. Mason, and H.S. Rzepa, \"Digital Data Repositories in Chemistry and Their Integration with Journals and Electronic Notebooks\", <i>Journal of Chemical Information and Modeling<\/i>, vol. 54, pp. 2627-2635, 2014. <a href=\"https:\/\/doi.org\/10.1021\/ci500302p\">https:\/\/doi.org\/10.1021\/ci500302p<\/a>\n\n<\/li>\n<li id=\"ITEM-24245-1\">D. Hudak, D. Johnson, A. Chalker, J. Nicklas, E. Franz, T. Dockendorf, and B. McMichael, \"Open OnDemand: A web-based client portal for HPC centers\", <i>Journal of Open Source Software<\/i>, vol. 3, pp. 622, 2018. <a href=\"https:\/\/doi.org\/10.21105\/joss.00622\">https:\/\/doi.org\/10.21105\/joss.00622<\/a>\n\n<\/li>\n<li id=\"ITEM-24245-2\">C. Cave-Ayland, M. Bearpark, C. Romain, and H. Rzepa, \"CHAMP is a HPC Access and Metadata Portal\", <i>Journal of Open Source Software<\/i>, vol. 7, pp. 3824, 2022. <a href=\"https:\/\/doi.org\/10.21105\/joss.03824\">https:\/\/doi.org\/10.21105\/joss.03824<\/a>\n\n<\/li>\n<\/ol>\n\n<\/div> <!-- kcite-section 24245 -->","protected":false},"excerpt":{"rendered":"<p>You might have noticed if you have read any of my posts here is that many of them have been accompanied since 2006 by supporting calculations, normally based on density functional theory (DFT) and these calculations are accompanied by a persistent identifier pointer\u2021 to a data repository publication. I have hitherto not gone into the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"activitypub_content_warning":"","activitypub_content_visibility":"","activitypub_max_image_attachments":5,"activitypub_interaction_policy_quote":"anyone","activitypub_status":"","footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[2],"tags":[],"ppma_author":[2661],"class_list":["post-24245","post","type-post","status-publish","format-standard","hentry","category-chemical-it"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>HPC Access and Metadata Portal (CHAMP). - Henry Rzepa&#039;s Blog<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=24245\" \/>\n<meta property=\"og:locale\" content=\"en_GB\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"HPC Access and Metadata Portal (CHAMP). - Henry Rzepa&#039;s Blog\" \/>\n<meta property=\"og:description\" content=\"You might have noticed if you have read any of my posts here is that many of them have been accompanied since 2006 by supporting calculations, normally based on density functional theory (DFT) and these calculations are accompanied by a persistent identifier pointer\u2021 to a data repository publication. I have hitherto not gone into the [&hellip;]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=24245\" \/>\n<meta property=\"og:site_name\" content=\"Henry Rzepa&#039;s Blog\" \/>\n<meta property=\"article:published_time\" content=\"2021-09-13T13:40:29+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2022-02-11T08:39:17+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/09\/Screenshot-833-1024x341.jpg\" \/>\n<meta name=\"author\" content=\"Henry Rzepa\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Henry Rzepa\" \/>\n\t<meta name=\"twitter:label2\" content=\"Estimated reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"5 minutes\" \/>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"HPC Access and Metadata Portal (CHAMP). - Henry Rzepa&#039;s Blog","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=24245","og_locale":"en_GB","og_type":"article","og_title":"HPC Access and Metadata Portal (CHAMP). - Henry Rzepa&#039;s Blog","og_description":"You might have noticed if you have read any of my posts here is that many of them have been accompanied since 2006 by supporting calculations, normally based on density functional theory (DFT) and these calculations are accompanied by a persistent identifier pointer\u2021 to a data repository publication. 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Such displacement at silicon famously proceeds by a quite different mechanism, which\u00a0I here quantify with\u2026","rel":"","context":"In &quot;reaction mechanism&quot;","block_context":{"text":"reaction mechanism","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=1086"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":16902,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=16902","url_meta":{"origin":24245,"position":1},"title":"\u03c3 or \u03c0 nucleophilic reactivity of imines? A mechanistic twist emerges.","author":"Henry Rzepa","date":"September 28, 2016","format":false,"excerpt":"The story so far. Imines react with a peracid to form either a nitrone (\u03c3-nucleophile) or an oxaziridine (\u03c0-nucleophile). The balance between the two is on an experimental\u00a0knife-edge, being strongly influenced by substituents on the imine. 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Here to produce some reference points for further discussion I look at the dipole moment of glycine, the classic\u00a0zwitterion (an internal ion-pair). Dielectric relaxation studies of glycine-water mixtures yield values that range from\u00a015.7D to 11.9D although these\u2026","rel":"","context":"In &quot;crystal_structure_mining&quot;","block_context":{"text":"crystal_structure_mining","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=1745"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2016\/12\/051.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":27784,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=27784","url_meta":{"origin":24245,"position":4},"title":"Mechanism of the Masamune-Bergman reaction. Part 4. 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As discussed in this review article, the trisulfide linkage is reduced and the resulting\u2026","rel":"","context":"In &quot;Interesting chemistry&quot;","block_context":{"text":"Interesting chemistry","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=4"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":16292,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=16292","url_meta":{"origin":24245,"position":5},"title":"Collaborative  FAIR data sharing.","author":"Henry Rzepa","date":"April 17, 2016","format":false,"excerpt":"I want to describe a recent attempt by a group of collaborators to share the research data associated with their just published article. I am here introducing things in a hierarchical form (i.e. not necessarily the serial order in which actions were taken). 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