Software · head to head
Fluentd vs Elastic APM
The short version
- Each has a real cost: Fluentd fluentd needs more than 60 MB of memory at runtime, against roughly 450 KB for Fluent Bit; Elastic APM pricing is not published on the product page; cost follows the underlying Elastic deployment rather than being quoted per host or per service
- They diverge on capability: Fluentd covers Log collection, Elastic APM covers Performance monitoring.
Where they differ
Only the attributes on which Fluentd and Elastic APM actually diverge.
| Attribute | Fluentd | Elastic APM |
|---|
Identical on both: starting price (Free), pricing model (open-source), free tier (Yes), platforms (Web, Api), user rating (Not yet rated), category (Unknown), founded (2011).
What each one covers
Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.
Only in Fluentd
- Log collection
- Data parsing
- Filtering and buffering
- Event routing
Only in Elastic APM
- Performance monitoring
- Error tracking
- Transaction tracing
- Custom metrics
Both cover
- API
- Webhooks
- REST
- Web support
- Api support
What people use each for
The jobs each tool is most often brought in to do.
Fluentd
- Unified log collection and routing from many sources to many destinationsnot Elastic APM
- Parsing and transforming log records before forwardingnot Elastic APM
- Aggregating logs from containers into Elasticsearch, S3 or a SIEMnot Elastic APM
Elastic APM
- Distributed tracing across microservicesnot Fluentd
- Auto-instrumenting Java, .NET, Python, Go, Node.js, Ruby, PHP and C++ servicesnot Fluentd
- OpenTelemetry-native collection through the Elastic distributionsnot Fluentd
- Correlating latency and errors with machine learningnot Fluentd
- Monitoring LLM calls alongside application tracesnot Fluentd
Where each one falls short
Documented limitations, not opinions. Every one is a constraint you would hit in normal use.
Fluentd
- Fluentd needs more than 60 MB of memory at runtime, against roughly 450 KB for Fluent Bit
- Fluentd is built as a Ruby gem and depends on other gems, so a Ruby runtime is required
- Its capability comes from over 1,000 external plugins rather than built in functionality, so each added input or output is a separate dependency
- The Fluent Bit documentation states that cloud providers have switched from Fluentd to Fluent Bit for performance and compatibility and calls Fluent Bit the next generation solution
Elastic APM
- Pricing is not published on the product page; cost follows the underlying Elastic deployment rather than being quoted per host or per service
- Self-managed deployment means running and scaling Elasticsearch yourself
- Serverless does not carry every capability the hosted option does
Pricing, plan by plan
Fluentd
Free- FreeFree
- Log collection
- Data parsing
- Filtering and buffering
Elastic APM
Free- FreeFree
- Performance monitoring
- Error tracking
- Transaction tracing
Which should you pick?
Choose Fluentd if
- You need log collection.
- You want to start without paying.
- You work on Web, Api.
- You also want data parsing.
Choose Elastic APM if
- You need performance monitoring.
- You want to start without paying.
- You work on Web, Api.
- You also want error tracking.
Questions people ask
- Is Fluentd or Elastic APM better?
- Neither clearly leads. Fluentd starts at Free and Elastic APM at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
- Which is cheaper, Fluentd or Elastic APM?
- Fluentd starts at Free and Elastic APM at Free.
- Does Fluentd or Elastic APM run on more platforms?
- Both run on Web, Api, so platform support will not decide this one for you.
- Can I use Fluentd for free?
- Both have a free tier, so you can try either at no cost before committing.
- What is Fluentd best used for?
- Fluentd is most often used for unified log collection and routing from many sources to many destinations, parsing and transforming log records before forwarding, aggregating logs from containers into elasticsearch, s3 or a siem. Of those, unified log collection and routing from many sources to many destinations and parsing and transforming log records before forwarding are not what Elastic APM is typically brought in for.
- What can Fluentd do that Elastic APM cannot?
- Fluentd covers Log collection, Data parsing, Filtering and buffering, Event routing. Elastic APM covers Performance monitoring, Error tracking, Transaction tracing, Custom metrics. Both handle API, Webhooks, REST, Web support.