--- title: This is why your Node.js application is slow | daily.dev description: Many performance-related issues in Node.js applications have to do with how promises are implemented. Async/await blocks the event loop when not correctly... canonical: https://daily.dev/posts/this-is-why-your-node-js-application-is-slow-v3umojdzi twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: This is why your Node.js application is slow | daily.dev og:description: Many performance-related issues in Node.js applications have to do with how promises are implemented. Async/await blocks the event loop when not correctly... og:url: https://daily.dev/posts/this-is-why-your-node-js-application-is-slow-v3umojdzi og:image: https://api.daily.dev/og/posts/V3UMojdzi.png og:image:alt: This is why your Node.js application is slow og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # This is why your Node.js application is slow **[DEV](https://daily.dev/sources/devto)** · [@imichaelowolabi](https://daily.dev/imichaelowolabi) · 5 min read · 95 upvotes · 6 comments ## Summary Many performance-related issues in Node.js applications have to do with how promises are implemented. Async/await blocks the event loop when not correctly used. blocking it means that other parts of the application will suffer because they will not get executed on time and that affects the overall performance. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Community discussion Top comments from developers on daily.dev. **@suco** · 1 upvotes > i don't know if this article are correctly. A lot of peoples on coments discussed about point in the artcle to be or not right about try/catch,I/O blocking function, among other things. Im still confused but anyway its a good read **@random\_user** · 1 upvotes > thanks for the reminder about looping and parallel vs sequential 👍🏻 **@raulmarindev** · 0 upvotes > From what I understand the article is pointing out that, when starting async operations close together in our code, we should consider if they could be started in parallel instead of sequentially. Additionally, as stated in the article comments, the event loop is not being blocked in any of its examples. This StackOverflow question offers good info on the matter: https://stackoverflow.com/questions/30823653/is-node-js-native-promise-all-processing-in-parallel-or-sequentially ## Similar posts on daily.dev - [Don’t just attend KubeCon \+ CloudNativeCon, Merge Forward your experience\!](https://daily.dev/posts/don-t-just-attend-kubecon-cloudnativecon-merge-forward-your-experience--l0rpp73x8) · CNCF · 1 upvotes · 0 comments - [Announcing H2 2026 KCDs](https://daily.dev/posts/announcing-h2-2026-kcds-m96goajm1) · CNCF · 1 upvotes · 0 comments - [Two months of Open Community Groups](https://daily.dev/posts/two-months-of-open-community-groups-asf52zhbs) · CNCF · 0 upvotes · 0 comments --- Tags: [#nodejs](https://daily.dev/tags/nodejs) [View this post on daily.dev](https://daily.dev/posts/this-is-why-your-node-js-application-is-slow-v3umojdzi) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"This is why your Node.js application is slow","url":"https://daily.dev/posts/this-is-why-your-node-js-application-is-slow-v3umojdzi","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/this-is-why-your-node-js-application-is-slow-v3umojdzi"},"datePublished":"2022-02-09T14:25:38.355Z","dateModified":"2022-02-10T06:12:59.885Z","description":"Many performance-related issues in Node.js applications have to do with how promises are implemented. Async/await blocks the event loop when not correctly...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/3afca9a7722cc6adae3a777183168db6","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/3afca9a7722cc6adae3a777183168db6","isAccessibleForFree":true,"articleSection":"DEV","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Person","name":"Michael Owolabi","url":"https://daily.dev/imichaelowolabi","image":"https://avatars.githubusercontent.com/u/20207295?v=4","interactionStatistic":{"@type":"InteractionCounter","interactionType":{"@type":"EndorseAction"},"userInteractionCount":80}},"commentCount":6,"discussionUrl":"https://daily.dev/posts/this-is-why-your-node-js-application-is-slow-v3umojdzi","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":95},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":6}],"keywords":"nodejs","timeRequired":"PT5M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"DEV","item":"https://daily.dev/sources/devto"},{"@type":"ListItem","position":3,"name":"This is why your Node.js application is slow"}]} {"@context":"https://schema.org","@type":"WebPage","@id":"https://daily.dev/posts/this-is-why-your-node-js-application-is-slow-v3umojdzi","comment":[{"@type":"Comment","text":"i don’t know if this article are correctly. A lot of peoples on coments discussed about point in the artcle to be or not right about try/catch,I/O blocking function, among other things. Im still confused but anyway its a good read","datePublished":"2022-02-12T19:09:58.846Z","url":"https://daily.dev/posts/V3UMojdzi#c-uujcxZRSM","author":{"@type":"Person","name":"lucas de frança","url":"https://daily.dev/suco","image":"https://lh3.googleusercontent.com/a-/AOh14Gg7r75Fe5vdQ8mpTIulbymN-QsZs123-3wxa9t9=s100"},"interactionStatistic":{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":1}},{"@type":"Comment","text":"thanks for the reminder about looping and parallel vs sequential 👍🏻","datePublished":"2022-02-09T19:16:16.151Z","url":"https://daily.dev/posts/V3UMojdzi#c-bEh7popdW","author":{"@type":"Person","name":"Joshua Jarman","url":"https://daily.dev/random_user","image":"https://media.daily.dev/image/upload/f_auto/v1632349791/avatars/f857f24c9be64a05bcc33d248c2e9b23"},"interactionStatistic":{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":1}},{"@type":"Comment","text":"From what I understand the article is pointing out that, when starting async operations close together in our code, we should consider if they could be started in parallel instead of sequentially. Additionally, as stated in the article comments, the event loop is not being blocked in any of its examples. This StackOverflow question offers good info on the matter: https://stackoverflow.com/questions/30823653/is-node-js-native-promise-all-processing-in-parallel-or-sequentially","datePublished":"2022-02-13T11:33:12.053Z","url":"https://daily.dev/posts/V3UMojdzi#c-HZkN4z8lZ","author":{"@type":"Person","name":"Raúl Marín","url":"https://daily.dev/raulmarindev","image":"https://media.daily.dev/image/upload/s--LOBtNjbr--/f_auto,q_auto/v1704035607/avatars/avatar_24f3bf992b6e46c188b91e9cf4b7cd01"}}]} ```