java-procfs-mbeans-agent

Java agent to make /proc metrics available as MXBeans, which is mainly intended for use with java-prometheus-metrics-agent to send /proc metrics to Prometheus.

WARNING (2017-11-27) I just started this project and should not be considered production-ready yet. Also, I'm developing this on linux 4.13 so might not work well on older kernels for now.

Project status

As of now (2020-01-12), I consider this project a failure due to the following reasons:

• Extra layers in observability (/proc -> MBeans -> Prometheus format) makes it harder to reach and dig into kernel code that produces the metric. Moreover, this wastes CPU and other resources.
• JVM has GC. If JVM stops due to long GC or something, metrics become unavailable, which is not good. We then have to investigate why they are missing.
• Kubernetes now has sharedProcessNamespaces. When enabled, process-specific (/proc/self/io, etc.) and namespaced metrics are accessible from other containers in a Pod. It's better to add an exporter sidecar that scrapes /proc/PID/io, etc.
• This agent cannot be used for non-JVM apps. I'm sure using a separate tool for non-JVM apps will be a headache because of different metric names, etc.

Once I find a better alternative for my use (or build one myself), this repository will be archived.

Installation

Building from source

git clone https://github.com/eiiches/java-procfs-mbeans-agent.git
cd java-procfs-mbeans-agent
mvn clean package

Then, copy target/java-procfs-mbeans-agent-{version}.jar to your desired location.

Downloading from Maven Central

curl -O 'https://repo1.maven.org/maven2/net/thisptr/java-procfs-mbeans-agent/0.0.4/java-procfs-mbeans-agent-0.0.4.jar'

Usage

java -javaagent:/path/to/java-procfs-mbeans-agent-$VERSION.jar ...

Current Status

path	status	requirements
/proc/buddyinfo	DONE
/proc/cpuinfo
/proc/diskstats	DONE
/proc/interrupts
/proc/loadavg	DONE
/proc/meminfo	DONE
/proc/net/dev
/proc/net/netstat	DONE
/proc/net/snmp6	DONE
/proc/net/snmp	DONE
/proc/net/sockstat6	DONE
/proc/net/sockstat	DONE
/proc/net/stat/arp_cache
/proc/net/stat/ndisc_cache
/proc/net/stat/nf_conntrack
/proc/net/stat/rt_cache
/proc/pagetypeinfo
/proc/schedstat
/proc/self/io	DONE
/proc/self/stat	DONE
/proc/self/statm	DONE
/proc/self/sched		CONFIG_SCHED_DEBUG
/proc/slabinfo
/proc/softirqs	DONE
/proc/stat	DONE
/proc/swaps
/proc/sys/fs/aio-nr
/proc/sys/fs/dentry-state
/proc/sys/fs/file-nr
/proc/sys/fs/inode-nr
/proc/sys/fs/inode-state
/proc/sys/kernel/pty/nr
/proc/sys/kernel/random/entropy_avail
/proc/uptime
/proc/vmstat	DONE
/proc/zoneinfo
/sys/fs/cgroup/cpu	DONE
/sys/fs/cgroup/cpuacct	DONE
/sys/fs/cgroup/memory	DONE
/sys/fs/cgroup/blkio

License

The Apache License, Version 2.0