The latest articles on DEV Community by Manoj Shukla (@manoj_from_revisit_dot_tech). https://dev.to/manoj_from_revisit_dot_tech https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F3281921%2Ff27d6176-6b5c-4763-a9d6-14edc2dc23b6.jpeg https://dev.to/manoj_from_revisit_dot_tech en Manoj Shukla Sat, 21 Jun 2025 09:33:02 +0000 https://dev.to/manoj_from_revisit_dot_tech/mongodb-80-performance-is-36-higher-nope-its-not--35jk https://dev.to/manoj_from_revisit_dot_tech/mongodb-80-performance-is-36-higher-nope-its-not--35jk <p><strong>TLDR:</strong> If your app is performance critical, think twice, thrice before upgrading to MongoDB 7.0 and 8.0.</p> <h2> Here is why… </h2> <p>One day I was reading about something and landed up on <a href="https://www.mongodb.com/blog/post/mongodb-8-0-raising-the-bar?ref=revisit.tech" rel="noopener noreferrer">a blog post shared by the CTO of the MongoDB</a>. The post surprised me with a claim that the MongoDB 8.0 is their the most secure and performant version ever. He claimed a whoping 36% to 50% reduction in Query Time. I don’t know know why but the post was not satisfying my mind. So I looked for few comparisons post, benchmarking results, tweak and tune settings post with comparing results like “before” and “after”.</p> <p>This search led me to an interesting thread posted on MongoDB’s official community forum. The thread titled <a href="https://www.mongodb.com/community/forums/t/performance-drop-after-upgrade-6-0-10-7-0-1/246712?ref=revisit.tech" rel="noopener noreferrer">Performance Drop After Upgrade 6.0.10 &gt; 7.0.1</a> was more interesting , practical and insightful than the many one-sided benchmark results. Plus, it was all contributed by community members (users) of MongoDB (community &amp; Atlas both).</p> <p>One of the user starts the above thread and posts some details about his/her odd findings, and asks for confirmation-cum-clarification.</p> <p><a href="https://media2.dev.to/dynamic/image/width=800%2Cheight=%2Cfit=scale-down%2Cgravity=auto%2Cformat=auto/https%3A%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Farticles%2Fc7j3aexof54lk41on8kt.png" class="article-body-image-wrapper"><img src="https://media2.dev.to/dynamic/image/width=800%2Cheight=%2Cfit=scale-down%2Cgravity=auto%2Cformat=auto/https%3A%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Farticles%2Fc7j3aexof54lk41on8kt.png" alt="a user asked question when performance dropped after upgrading" width="800" height="565"></a></p> <p>The user’s query got a reply from MongoDB Employee, asking a few questions and a guess for root cause.</p> <p><a href="https://media2.dev.to/dynamic/image/width=800%2Cheight=%2Cfit=scale-down%2Cgravity=auto%2Cformat=auto/https%3A%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Farticles%2Ftmutvcuw854d7dbi8e7g.png" class="article-body-image-wrapper"><img src="https://media2.dev.to/dynamic/image/width=800%2Cheight=%2Cfit=scale-down%2Cgravity=auto%2Cformat=auto/https%3A%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Farticles%2Ftmutvcuw854d7dbi8e7g.png" alt="MongoDB Employee asks for clarification, so far so good" width="800" height="472"></a></p> <p>The user then confirms, and also shares a finding that the “if downgraded to 6.0 again, restores the same performance”.</p> <p><a href="https://media2.dev.to/dynamic/image/width=800%2Cheight=%2Cfit=scale-down%2Cgravity=auto%2Cformat=auto/https%3A%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Farticles%2Fj4dh0fmyqrxdt1qarfr2.png" class="article-body-image-wrapper"><img src="https://media2.dev.to/dynamic/image/width=800%2Cheight=%2Cfit=scale-down%2Cgravity=auto%2Cformat=auto/https%3A%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Farticles%2Fj4dh0fmyqrxdt1qarfr2.png" alt="user confirms downgradng back to 6.0 performs better" width="800" height="258"></a></p> <p>And there goes a list of other users claiming the exact same behaviour that emphasises the performance issue with Mongo DB 7.0. I am not posting those many screenshots to cut-short the blog length, but you can always refer to the above thread link and checkout yourself.</p> <p>MongoDB 8.0 claims to be faster on reads by 36% is nowhere mentioned from which version they compared the results and did the math. The claim is actually by comparing the MongoDB 8.0 against MongoDB 7.0. I’ll try to prove later on..</p> <h2> The Irony </h2> <p>The MongoDB 7.0 was indeed a bad performer (until 7.0.14-rc was released). Imagine the performance of your existing MongoDB 6.0 gives a query result in fraction of seconds and when used same query and dataset on MongoDB 7.0 it gives result in ~7s (from one of the user’s finding). Now, if MongoDB 8.0 is compared against 7.0, and the results are 36-55 % faster, the real performance of MongoDB 8.0 as compared to 6.0 will be actually still smaller.</p> <h3> What was the reason behind the performance drop? </h3> <p>Read full details at my blog platform here : <a href="https://revisit.tech/blog/mongodb-8-0-performanace-is-36-percent-higher-but-there-is-a-catch/" rel="noopener noreferrer">https://revisit.tech/blog/mongodb-8-0-performanace-is-36-percent-higher-but-there-is-a-catch/</a></p> <p>If you are on 6.0 or any other version and facing MongoDB performance decay issue, you must read <a href="https://revisit.tech/blog/mongodb-decay-over-time-how-deletes-and-updates-clog-your-database/" rel="noopener noreferrer">this finely crafted guide, explaining the root cause and the fix</a>.</p> <p>Hope you liked the article, please comment your thoughts if this post was helpful to you. If you find any problems, hit me in the comments, will try to reach out if possible!</p> <p>Have a great day !!</p> mongodb performance systemdesign programming