--- title: PLGM Has Grown Up: A New UI and Many More Features description: PLGM, Percona's MongoDB benchmark tool, has grown from a command-line-only tool into a full web application with a UI, query analysis, and Record & Replay.... canonical: https://daily.dev/posts/plgm-has-grown-up-a-new-ui-and-many-more-features-4dgtn3fty twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: PLGM Has Grown Up: A New UI and Many More Features | daily.dev og:description: PLGM, Percona's MongoDB benchmark tool, has grown from a command-line-only tool into a full web application with a UI, query analysis, and Record & Replay.... og:url: https://daily.dev/posts/plgm-has-grown-up-a-new-ui-and-many-more-features-4dgtn3fty og:image: https://api.daily.dev/og/posts/4DGtN3fTy.png og:image:alt: PLGM Has Grown Up: A New UI and Many More Features 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. # PLGM Has Grown Up: A New UI and Many More Features **[Percona Blog](https://daily.dev/sources/percona)** · 14 min read · 0 upvotes · 0 comments ## Summary PLGM, Percona's MongoDB benchmark tool, has grown from a command-line-only tool into a full web application with a UI, query analysis, and Record & Replay. Launching it with the --webui flag opens a local dashboard for configuring and monitoring workloads. A new Query & Index Analysis tab scores each query shape's scan efficiency from 0 to 100 and suggests indexes; in one example, adding an index raised a query's efficiency from 0 to 100 and cut its latency from 81 ms to about 1 ms. Record & Replay captures real traffic and replays it identically against up to eight MongoDB servers at once for side-by-side comparison, and a Trends tab tracks results across saved runs (five kept by default, up to ten pinnable). ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How can I test whether upgrading my MongoDB version will hurt performance before I actually do it? Run your own workload, not a generic benchmark, against both your current MongoDB version and the candidate version, then compare results. PLGM, a Percona benchmark tool, supports this directly through its Record & Replay feature, which sends the exact same recorded operations to up to eight MongoDB instances at once, checks they start with identical document counts and indexes, and compares latency, scan efficiency, and workload impact per query shape automatically. _daily.dev surfaces tooling like this for developers validating a MongoDB version upgrade before it ships._ ### What is scan efficiency in a MongoDB query benchmark and how is it calculated? Scan efficiency is a 0 to 100 score (higher is better) measuring how much work the server did per result returned. It is based on documents examined per result, index keys examined per result, and whether an unnecessary collection scan occurred. It is a custom rule-of-thumb metric from the PLGM tool, not an official MongoDB metric, used to flag queries that look fast now but scan excessively. _daily.dev helps developers tracking down inefficient MongoDB queries find practical scoring approaches like this._ ### How do I replay captured production MongoDB traffic for load testing? Point the PLGM benchmark tool at mongod JSON logs (version 4.4 and later) or a system.profile export, and it converts them into a replayable recording. Each client connection becomes its own worker, preserving the original operation order and timing where possible, with anything that can't be replayed exactly flagged in the output. _daily.dev helps engineers building realistic MongoDB load tests from real production logs stay on top of tools like this._ ## Similar posts on daily.dev - [pgAdmin 4 v9.13 Released](https://daily.dev/posts/pgadmin-4-v9-13-released-a3zc0kcvy) · PostgreSQL · 6 upvotes · 0 comments - [The open way of Percona Search for MongoDB](https://daily.dev/posts/the-open-way-of-percona-search-for-mongodb-ocg8oei4i) · Percona Blog · 0 upvotes · 0 comments - [I created a playground for 110 database systems](https://daily.dev/posts/i-created-a-playground-for-110-database-systems-ljnd0hsab) · ClickHouse · 8 upvotes · 0 comments - [How We Built an Automated, Production-Ready Sharded MongoDB Infrastructure](https://daily.dev/posts/how-we-built-an-automated-production-ready-sharded-mongodb-infrastructure-n1vi9g1lo) · Trendyol Tech · 1 upvotes · 0 comments --- Tags: [#database](https://daily.dev/tags/database), [#mongodb](https://daily.dev/tags/mongodb) [View this post on daily.dev](https://daily.dev/posts/plgm-has-grown-up-a-new-ui-and-many-more-features-4dgtn3fty) ```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":"PLGM Has Grown Up: A New UI and Many More Features","url":"https://daily.dev/posts/plgm-has-grown-up-a-new-ui-and-many-more-features-4dgtn3fty","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/plgm-has-grown-up-a-new-ui-and-many-more-features-4dgtn3fty"},"datePublished":"2026-10-29T15:56:20.913Z","dateModified":"2026-10-29T15:59:34.620Z","description":"PLGM, Percona's MongoDB benchmark tool, has grown from a command-line-only tool into a full web application with a UI, query analysis, and Record \u0026 Replay....","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/16e1701093e21468a47c9c39a9892522?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/16e1701093e21468a47c9c39a9892522?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Percona Blog","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":"Organization","name":"Percona Blog","logo":"https://media.daily.dev/image/upload/s--Lb3XkBh3--/f_auto,q_auto/v1780213412/logos/percona?_a=BAMAMiWQ0","url":"https://daily.dev/sources/percona"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/plgm-has-grown-up-a-new-ui-and-many-more-features-4dgtn3fty","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"database,mongodb","timeRequired":"PT14M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Percona Blog","item":"https://daily.dev/sources/percona"},{"@type":"ListItem","position":3,"name":"PLGM Has Grown Up: A New UI and Many More Features"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/plgm-has-grown-up-a-new-ui-and-many-more-features-4dgtn3fty#faq","mainEntity":[{"@type":"Question","name":"How can I test whether upgrading my MongoDB version will hurt performance before I actually do it?","acceptedAnswer":{"@type":"Answer","text":"Run your own workload, not a generic benchmark, against both your current MongoDB version and the candidate version, then compare results. 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