Ojo - Lightweight OTel Collector

Ojo is a lightweight host metrics agent written in Rust that collects system and process metrics and exports them via OpenTelemetry OTLP.

Supported Platforms

• Linux
• Windows
• Solaris (in progress, platform-constrained, built, but not tested)

What Ojo Does

• Polls host metrics on a fixed interval
• Optionally collects per-process metrics
• Computes deltas and rates where applicable
• Exports to any OTLP-compatible backend directly or through an OpenTelemetry Collector
• Supports optional extension services for Docker, GPU, sensors, MySQL, Postgres, NFS client stats, NGINX status, Redis INFO telemetry, systemd unit/job health, low-level systrace metrics/traces, and low-cardinality syslog ingestion

Optional extension services (sidecars)

These binaries are separate workspace crates under services/<name>/. Each runs independently, reads its own YAML (next to the binary or via --config), and exports OTLP metrics to the same endpoint as the main ojo agent. Build from the repo root with cargo build -p <package> --release or use cargo run -p <package> as below.

Service	Cargo package	Example config	Metric prefix (examples)
Docker	ojo-docker	services/docker/docker.yaml	system.docker.*
GPU (NVIDIA)	ojo-gpu	services/gpu/gpu.yaml	system.gpu.*
Sensors	ojo-sensors	services/sensors/sensors.yaml	system.sensor.*
MySQL	ojo-mysql	services/mysql/mysql.yaml	system.mysql.*
Postgres	ojo-postgres	services/postgres/postgres.yaml	system.postgres.*
NFS client	ojo-nfs-client	services/nfs-client/nfs-client.yaml	system.nfs_client.*
NGINX	ojo-nginx	services/nginx/nginx.yaml	system.nginx.*
Redis	ojo-redis	services/redis/redis.yaml	system.redis.*
Systemd	ojo-systemd	services/systemd/systemd.yaml	system.systemd.*
Systrace	ojo-systrace	services/systrace/systrace.yaml	system.systrace.*
Syslog	ojo-syslog	services/syslog/syslog.yaml	system.syslog.*

Shared OTLP and filtering helpers live in crates/host-collectors. Grafana dashboards for each extension are under grafana/ (docker.json, gpu.json, sensors.json, mysql.json, postgres.json, nfs-client.json, nginx.json, redis.json, systemd.json, systrace.json, syslog.json).

Release archives include the main ojo agent and all sidecar services for Linux (-unix) and Windows (-win).

Collected Metrics Reference

This section documents the metric families emitted by the core ojo host agent and the additional sidecar services.

Core host agent (ojo) by platform

Metric family / namespace	Linux metrics	Windows metrics	Solaris metrics
Metadata and QA classification	system.metric.support_state, system.metric.classification	system.metric.support_state, system.metric.classification	system.metric.support_state, system.metric.classification
CPU time and utilization	system.cpu.time, system.cpu.utilization, system.cpu.core.utilization, system.cpu.core.system_ratio, system.cpu.core.iowait_ratio	system.cpu.time, system.cpu.utilization, system.cpu.core.utilization, system.cpu.core.system_ratio	system.cpu.time, system.cpu.utilization, system.cpu.core.utilization, system.cpu.core.system_ratio
CPU/load averages	system.cpu.load_average.1m, system.cpu.load_average.5m, system.cpu.load_average.15m, system.linux.load.runnable, system.linux.load.entities, system.linux.load.latest_pid	system.cpu.load_average.1m, system.cpu.load_average.5m, system.cpu.load_average.15m	system.cpu.load_average.1m, system.cpu.load_average.5m, system.cpu.load_average.15m
Process counts and lifecycle	system.process.count, system.process.created, system.processes.running, system.processes.blocked, system.processes.forks	system.process.count, system.process.created, system.processes.running	system.process.count, system.process.created, system.processes.running, system.processes.blocked, system.processes.forks
Memory and swap (base)	system.memory.total, system.memory.free, system.memory.available, system.swap.total, system.swap.free, system.memory.used_ratio, system.swap.used_ratio, system.memory.commit_limit, system.memory.committed_as	system.memory.total, system.memory.free, system.memory.available, system.swap.total, system.swap.free, system.memory.used_ratio, system.swap.used_ratio, system.memory.commit_limit, system.memory.committed_as	system.memory.total, system.memory.free, system.memory.available, system.swap.total, system.swap.free, system.memory.used_ratio, system.swap.used_ratio, system.memory.commit_limit, system.memory.committed_as
Memory and swap (extended fields)	system.memory.buffers, system.memory.active, system.memory.inactive, system.memory.slab, system.memory.hugepages_total, system.memory.hugepages_free, system.swap.cached, system.memory.dirty_writeback_ratio	N/A	system.memory.buffers, system.memory.active, system.memory.inactive, system.memory.slab, system.swap.cached (collector-dependent)
Paging and swap rates	system.paging.faults, system.paging.operations, system.swap.operations, system.paging.faults_per_sec, system.paging.major_faults_per_sec, system.paging.page_ins_per_sec, system.paging.page_outs_per_sec, system.swap.ins_per_sec, system.swap.outs_per_sec	system.paging.faults, system.paging.operations, system.swap.operations, system.paging.faults_per_sec, system.paging.major_faults_per_sec, system.paging.page_ins_per_sec, system.paging.page_outs_per_sec, system.swap.ins_per_sec, system.swap.outs_per_sec	system.paging.faults, system.paging.operations, system.swap.operations, system.paging.faults_per_sec, system.paging.major_faults_per_sec, system.paging.page_ins_per_sec, system.paging.page_outs_per_sec, system.swap.ins_per_sec, system.swap.outs_per_sec
Disk throughput, latency, and queueing	system.disk.io, system.disk.operations, system.disk.operation_time, system.disk.io_time, system.disk.read_bytes_per_sec, system.disk.write_bytes_per_sec, system.disk.total_bytes_per_sec, system.disk.ops_per_sec, system.disk.read_await, system.disk.write_await, system.disk.utilization, system.disk.queue_depth, system.disk.io_in_progress, system.disk.pending_operations	system.disk.io, system.disk.operations, system.disk.operation_time, system.disk.io_time, system.disk.read_bytes_per_sec, system.disk.write_bytes_per_sec, system.disk.total_bytes_per_sec, system.disk.ops_per_sec, system.disk.read_await, system.disk.write_await, system.disk.utilization, system.disk.queue_depth, system.disk.io_in_progress, system.disk.pending_operations	system.disk.io, system.disk.operations, system.disk.operation_time, system.disk.io_time, system.disk.read_bytes_per_sec, system.disk.write_bytes_per_sec, system.disk.total_bytes_per_sec, system.disk.ops_per_sec, system.disk.read_await, system.disk.write_await, system.disk.utilization, system.disk.queue_depth, system.disk.io_in_progress, system.disk.pending_operations
Network throughput and errors	system.network.io, system.network.packet.count, system.network.errors, system.network.packet.dropped, system.network.rx_bytes_per_sec, system.network.tx_bytes_per_sec, system.network.total_bytes_per_sec, system.network.rx_packets_per_sec, system.network.tx_packets_per_sec, system.network.rx_errors_per_sec, system.network.tx_errors_per_sec, system.network.rx_loss_ratio, system.network.tx_loss_ratio, system.network.mtu	system.network.io, system.network.packet.count, system.network.errors, system.network.packet.dropped, system.network.rx_bytes_per_sec, system.network.tx_bytes_per_sec, system.network.total_bytes_per_sec, system.network.rx_packets_per_sec, system.network.tx_packets_per_sec, system.network.rx_errors_per_sec, system.network.tx_errors_per_sec, system.network.rx_loss_ratio, system.network.tx_loss_ratio, system.network.mtu	system.network.io, system.network.packet.count, system.network.errors, system.network.packet.dropped, system.network.rx_bytes_per_sec, system.network.tx_bytes_per_sec, system.network.total_bytes_per_sec, system.network.rx_packets_per_sec, system.network.tx_packets_per_sec, system.network.rx_errors_per_sec, system.network.tx_errors_per_sec, system.network.rx_loss_ratio, system.network.tx_loss_ratio, system.network.mtu
Filesystem and mount inventory	system.filesystem.usage, system.filesystem.mount.state	system.filesystem.usage, system.filesystem.mount.state	system.filesystem.usage, system.filesystem.mount.state
Per-process common metrics	process.cpu.time, process.cpu.utilization, process.memory.rss, process.memory.usage, process.thread.count, process.start_time, process.io.read_bytes, process.io.write_bytes, process.priority, process.memory.vm_size	process.cpu.time, process.cpu.utilization, process.memory.rss, process.memory.usage, process.thread.count, process.start_time, process.io.read_bytes, process.io.write_bytes, process.priority, process.memory.vm_size	process.cpu.time, process.cpu.utilization, process.memory.rss, process.memory.usage, process.thread.count, process.start_time, process.io.read_bytes, process.io.write_bytes, process.priority, process.memory.vm_size
Linux process extensions	process.linux.nice, process.linux.io.cancelled_write_bytes, process.linux.start_time, process.linux.scheduler, process.oom_score	N/A	N/A
Windows process extensions	N/A	process.memory.working_set, process.memory.peak_working_set, process.memory.pagefile_usage, process.memory.private_bytes, process.memory.commit_charge	N/A
Linux kernel/proc namespaces	system.linux.pid.max, system.linux.entropy, system.linux.pressure, system.linux.pressure.stall_time, system.linux.schedstat, system.linux.runqueue.depth, system.linux.slab, system.linux.cgroup, system.linux.swap.device.size, system.linux.zoneinfo, system.linux.buddy.blocks, system.linux.net.snmp, system.linux.netstat, system.linux.net.softnet.drop_ratio	N/A	N/A
Windows kernel namespaces	N/A	system.windows.vmstat, system.windows.net.snmp, system.windows.interrupts, system.windows.dpc	N/A

Notes:

• Linux has the broadest namespace coverage (including system.linux.* and process.linux.*).
• Windows omits Linux-only families and publishes Windows-specific families under system.windows.*.
• Solaris currently uses the cross-platform families plus whichever optional fields are available from the Solaris collector.
• Current QA snapshot fixtures under tests/qa/ are Linux-focused; Windows and Solaris rows reflect the recorder/collector implementation paths.

Deep Audit: Additional Core Metrics By Platform

The summary table above is grouped by family. The lists below complete the inventory so every currently emitted core metric name is documented.

Linux additional metrics: process.context_switches, process.cpu.last_id, process.disk.io, process.io.chars, process.io.syscalls, process.memory.virtual, process.memory.vm_rss, process.paging.faults, process.parent_pid, process.unix.file_descriptor.count, system.boot.time, system.context_switches, system.cpu.cache.size, system.cpu.frequency, system.cpu.info, system.cpu.interrupts, system.cpu.softirqs, system.disk.avg_read_size, system.disk.avg_write_size, system.disk.logical_block_size, system.disk.physical_block_size, system.disk.read_ops_per_sec, system.disk.rotational, system.disk.time_in_progress, system.disk.time_reading, system.disk.time_writing, system.disk.weighted_time_in_progress, system.disk.write_ops_per_sec, system.linux.interrupts, system.linux.net.ip.in_discards_per_sec, system.linux.net.ip.out_discards_per_sec, system.linux.net.softnet.cpu.dropped, system.linux.net.softnet.cpu.processed, system.linux.net.softnet.cpu.time_squeezed, system.linux.net.softnet.dropped_per_sec, system.linux.net.softnet.processed_per_sec, system.linux.net.softnet.time_squeezed_per_sec, system.linux.net.tcp.retrans_segs_per_sec, system.linux.net.udp.in_errors_per_sec, system.linux.net.udp.rcvbuf_errors_per_sec, system.linux.softirqs, system.linux.swap.device.priority, system.linux.swap.device.used, system.linux.vmstat, system.memory.anon, system.memory.anon_hugepages, system.memory.cached, system.memory.dirty, system.memory.hugepage_size, system.memory.kernel_stack, system.memory.mapped, system.memory.page_tables, system.memory.shmem, system.memory.sreclaimable, system.memory.sunreclaim, system.memory.writeback, system.network.carrier_up, system.network.rx_compressed, system.network.rx_dropped, system.network.rx_drops_per_sec, system.network.rx_errors, system.network.rx_fifo, system.network.rx_frame, system.network.rx_multicast, system.network.rx_packets, system.network.speed, system.network.tx_carrier, system.network.tx_collisions, system.network.tx_compressed, system.network.tx_dropped, system.network.tx_drops_per_sec, system.network.tx_errors, system.network.tx_fifo, system.network.tx_packets, system.network.tx_queue_len, system.socket.count, system.uptime.

Windows additional metrics: process.context_switches, process.disk.io, process.io.chars, process.io.syscalls, process.paging.faults, process.parent_pid, process.unix.file_descriptor.count, system.boot.time, system.context_switches, system.cpu.cache.size, system.cpu.frequency, system.cpu.info, system.cpu.interrupts, system.cpu.softirqs, system.disk.avg_read_size, system.disk.avg_write_size, system.disk.logical_block_size, system.disk.physical_block_size, system.disk.read_ops_per_sec, system.disk.rotational, system.disk.time_in_progress, system.disk.time_reading, system.disk.time_writing, system.disk.weighted_time_in_progress, system.disk.write_ops_per_sec, system.memory.cached, system.network.carrier_up, system.network.rx_compressed, system.network.rx_dropped, system.network.rx_drops_per_sec, system.network.rx_errors, system.network.rx_fifo, system.network.rx_frame, system.network.rx_multicast, system.network.rx_packets, system.network.speed, system.network.tx_carrier, system.network.tx_collisions, system.network.tx_compressed, system.network.tx_dropped, system.network.tx_drops_per_sec, system.network.tx_errors, system.network.tx_fifo, system.network.tx_packets, system.network.tx_queue_len, system.socket.count, system.uptime.

Solaris additional metrics: process.context_switches, process.cpu.last_id, process.disk.io, process.io.chars, process.io.syscalls, process.memory.virtual, process.memory.vm_rss, process.paging.faults, process.parent_pid, process.unix.file_descriptor.count, system.boot.time, system.context_switches, system.cpu.cache.size, system.cpu.frequency, system.cpu.info, system.cpu.interrupts, system.cpu.softirqs, system.disk.avg_read_size, system.disk.avg_write_size, system.disk.logical_block_size, system.disk.physical_block_size, system.disk.read_ops_per_sec, system.disk.rotational, system.disk.time_in_progress, system.disk.time_reading, system.disk.time_writing, system.disk.weighted_time_in_progress, system.disk.write_ops_per_sec, system.linux.vmstat, system.memory.anon, system.memory.anon_hugepages, system.memory.cached, system.memory.dirty, system.memory.hugepage_size, system.memory.kernel_stack, system.memory.mapped, system.memory.page_tables, system.memory.shmem, system.memory.sreclaimable, system.memory.sunreclaim, system.memory.writeback, system.network.carrier_up, system.network.rx_compressed, system.network.rx_dropped, system.network.rx_drops_per_sec, system.network.rx_errors, system.network.rx_fifo, system.network.rx_frame, system.network.rx_multicast, system.network.rx_packets, system.network.speed, system.network.tx_carrier, system.network.tx_collisions, system.network.tx_compressed, system.network.tx_dropped, system.network.tx_drops_per_sec, system.network.tx_errors, system.network.tx_fifo, system.network.tx_packets, system.network.tx_queue_len, system.socket.count, system.uptime.

Additional sidecar services (contracted metrics)

The extension metric contracts are validated by tests/qa_extension_metric_contracts.rs.

Service	Namespace	Collected metrics (name -> semantic)
Docker (ojo-docker)	system.docker.*	system.docker.containers.total -> gauge system.docker.containers.running -> gauge system.docker.containers.stopped -> gauge system.docker.container.cpu.ratio -> gauge_ratio system.docker.container.memory.usage.bytes -> gauge system.docker.container.memory.limit.bytes -> gauge system.docker.container.network.rx.bytes -> gauge system.docker.container.network.tx.bytes -> gauge system.docker.container.block.read.bytes -> gauge system.docker.container.block.write.bytes -> gauge system.docker.source.available -> state
GPU (ojo-gpu)	system.gpu.*	system.gpu.devices -> inventory system.gpu.utilization.ratio -> gauge_ratio system.gpu.memory.used.bytes -> gauge system.gpu.memory.total.bytes -> gauge system.gpu.temperature.celsius -> gauge system.gpu.power.watts -> gauge system.gpu.throttled -> state system.gpu.source.available -> state
Sensors (ojo-sensors)	system.sensor.*	system.sensor.temperature.celsius -> gauge system.sensor.temperature.max.celsius -> gauge system.sensor.fan.rpm -> gauge system.sensor.voltage.volts -> gauge system.sensor.count -> inventory system.sensor.source.available -> state
MySQL (ojo-mysql)	system.mysql.*	system.mysql.source.available -> state system.mysql.up -> state system.mysql.connections -> gauge system.mysql.threads.running -> gauge system.mysql.queries.total -> counter system.mysql.slow_queries.total -> counter system.mysql.bytes.received.total -> counter system.mysql.bytes.sent.total -> counter system.mysql.queries.rate_per_second -> gauge_derived system.mysql.bytes.received.rate_per_second -> gauge_derived system.mysql.bytes.sent.rate_per_second -> gauge_derived
Postgres (ojo-postgres)	system.postgres.*	system.postgres.source.available -> state system.postgres.up -> state system.postgres.connections -> gauge system.postgres.transactions.committed.total -> counter system.postgres.transactions.rolled_back.total -> counter system.postgres.deadlocks.total -> counter system.postgres.blocks.read.total -> counter system.postgres.blocks.hit.total -> counter system.postgres.transactions.committed.rate_per_second -> gauge_derived system.postgres.transactions.rolled_back.rate_per_second -> gauge_derived
NFS client (ojo-nfs-client)	system.nfs_client.*	system.nfs_client.source.available -> state system.nfs_client.mounts -> inventory system.nfs_client.rpc.calls.total -> counter system.nfs_client.rpc.retransmissions.total -> counter system.nfs_client.rpc.auth_refreshes.total -> counter system.nfs_client.rpc.calls.rate_per_second -> gauge_derived system.nfs_client.rpc.retransmissions.rate_per_second -> gauge_derived
NGINX (ojo-nginx)	system.nginx.*	system.nginx.source.available -> state system.nginx.up -> state system.nginx.connections.active -> gauge system.nginx.connections.reading -> gauge system.nginx.connections.writing -> gauge system.nginx.connections.waiting -> gauge system.nginx.connections.accepted.total -> counter system.nginx.connections.handled.total -> counter system.nginx.requests.total -> counter system.nginx.connections.accepted.rate_per_second -> gauge_derived system.nginx.requests.rate_per_second -> gauge_derived
Redis (ojo-redis)	system.redis.*	system.redis.source.available -> state system.redis.up -> state system.redis.clients.connected -> gauge system.redis.clients.blocked -> gauge system.redis.memory.used.bytes -> gauge system.redis.memory.max.bytes -> gauge system.redis.uptime.seconds -> gauge system.redis.commands.processed.total -> counter system.redis.connections.received.total -> counter system.redis.keyspace.hits.total -> counter system.redis.keyspace.misses.total -> counter system.redis.keys.expired.total -> counter system.redis.keys.evicted.total -> counter system.redis.commands.processed.rate_per_second -> gauge_derived system.redis.connections.received.rate_per_second -> gauge_derived system.redis.keyspace.hit.ratio -> gauge_ratio
Systemd (ojo-systemd)	system.systemd.*	system.systemd.source.available -> state system.systemd.up -> state system.systemd.units.total -> gauge system.systemd.units.active -> gauge system.systemd.units.inactive -> gauge system.systemd.units.failed -> gauge system.systemd.units.activating -> gauge system.systemd.units.deactivating -> gauge system.systemd.units.reloading -> gauge system.systemd.units.not_found -> gauge system.systemd.units.maintenance -> gauge system.systemd.jobs.queued -> gauge system.systemd.jobs.running -> gauge system.systemd.failed_units.reported -> gauge system.systemd.units.failed.ratio -> gauge_ratio system.systemd.units.active.ratio -> gauge_ratio
Systrace (ojo-systrace)	system.systrace.*	system.systrace.source.available -> state system.systrace.up -> state system.systrace.tracefs.available -> state system.systrace.etw.available -> state system.systrace.tracing.on -> state system.systrace.tracers.available -> inventory system.systrace.events.total -> counter system.systrace.events.enabled -> counter system.systrace.buffer.total_kb -> gauge system.systrace.etw.sessions.total -> gauge system.systrace.etw.sessions.running -> gauge system.systrace.exporter.available -> state system.systrace.exporter.reconnecting -> state system.systrace.exporter.errors.total -> counter system.systrace.context_switches_per_sec -> gauge_derived system.systrace.interrupts_per_sec -> gauge_derived system.systrace.system_calls_per_sec -> gauge_derived system.systrace.system_calls.source -> inventory system.systrace.system_calls.coverage_ratio -> gauge_ratio system.systrace.dpcs_per_sec -> gauge_derived system.systrace.process_forks_per_sec -> gauge_derived system.systrace.run_queue.depth -> gauge_approximation system.systrace.processes.total -> gauge system.systrace.threads.total -> gauge system.systrace.trace.kernel_stack_samples.total -> counter system.systrace.trace.user_stack_samples.total -> counter system.systrace.collection.errors -> counter
Syslog (ojo-syslog)	system.syslog.*	system.syslog.source.available -> state system.syslog.up -> state system.syslog.journald.available -> state system.syslog.etw.available -> state system.syslog.kernel.dmesg.available -> state system.syslog.process.logs.available -> state system.syslog.application.logs.available -> state system.syslog.file.watch.targets.configured -> inventory system.syslog.file.watch.targets.active -> inventory system.syslog.buffer.capacity.records -> gauge system.syslog.buffer.queued.records -> gauge system.syslog.buffer.dropped.total -> counter system.syslog.exporter.available -> state system.syslog.exporter.reconnecting -> state system.syslog.logs.batch.size -> gauge system.syslog.logs.payload.bytes -> gauge system.syslog.collection.errors -> counter system.syslog.logs.collected.total -> counter system.syslog.logs.exported.total -> counter system.syslog.logs.retry.total -> counter system.syslog.logs.export.errors.total -> counter

Allowed semantic kinds for extensions are: counter, gauge, gauge_approximation, gauge_derived, gauge_derived_ratio, gauge_ratio, inventory, and state.

Repository Layout

src/main.rs                  Runtime loop and exporter flush behavior
src/config.rs                YAML/env config loader and validation
src/linux/                   Linux collector modules
src/windows/                 Windows collector modules
src/solaris/                 Solaris collector modules
src/delta.rs                 Delta and rate derivation
src/metrics/                 OTel metric instruments and recording
linux.yaml                   Linux config example
windows.yaml                 Windows config example
services/docker/docker.yaml  Docker extension config example
services/gpu/gpu.yaml        GPU extension config example
services/sensors/sensors.yaml Sensor extension config example
services/mysql/mysql.yaml    MySQL extension config example
services/postgres/postgres.yaml Postgres extension config example
services/nfs-client/nfs-client.yaml NFS client extension config example
services/nginx/nginx.yaml    NGINX extension config example
services/redis/redis.yaml    Redis extension config example
services/systemd/systemd.yaml Systemd extension config example
services/systrace/systrace.yaml Systrace extension config example
services/syslog/syslog.yaml     Syslog extension config example
grafana/docker.json          Docker dashboard
grafana/gpu.json             GPU dashboard
grafana/sensors.json         Sensors dashboard
grafana/mysql.json           MySQL dashboard
grafana/postgres.json        Postgres dashboard
grafana/nfs-client.json      NFS client dashboard
grafana/nginx.json           NGINX dashboard
grafana/redis.json           Redis dashboard
grafana/systemd.json         Systemd dashboard
grafana/systrace.json        Systrace dashboard
grafana/syslog.json          Syslog dashboard
otel.yaml                    OpenTelemetry Collector example
tests/qa_json_schema.rs      QA snapshot schema tests
tests/qa_platform_metric_contracts.rs  Platform metric namespace tests
tests/qa_extension_metric_contracts.rs Extension metric contract tests
services/docker/             Docker sidecar service crate
services/gpu/                GPU sidecar service crate
services/sensors/            Sensor sidecar service crate
services/mysql/              MySQL sidecar service crate
services/postgres/           Postgres sidecar service crate
services/nfs-client/         NFS client sidecar service crate
services/nginx/              NGINX sidecar service crate
services/redis/              Redis sidecar service crate
services/systemd/            Systemd sidecar service crate
services/systrace/           Systrace sidecar service crate
services/syslog/             Syslog sidecar service crate
crates/host-collectors/      Shared OTLP and metric helper crate
docker.dev/                  QA Dockerfiles and Compose services

Quick Start

1. Pick a config

Use one of the included examples: linux.yaml or windows.yaml.

2. Run

cargo run -- --config linux.yaml

cargo run -- --config windows.yaml

Optional extension services

cargo run -p ojo-docker -- --config services/docker/docker.yaml

cargo run -p ojo-gpu -- --config services/gpu/gpu.yaml

cargo run -p ojo-sensors -- --config services/sensors/sensors.yaml

cargo run -p ojo-mysql -- --config services/mysql/mysql.yaml

cargo run -p ojo-postgres -- --config services/postgres/postgres.yaml

cargo run -p ojo-nfs-client -- --config services/nfs-client/nfs-client.yaml

cargo run -p ojo-nginx -- --config services/nginx/nginx.yaml

cargo run -p ojo-redis -- --config services/redis/redis.yaml

cargo run -p ojo-systemd -- --config services/systemd/systemd.yaml

cargo run -p ojo-systrace -- --config services/systrace/systrace.yaml

cargo run -p ojo-syslog -- --config services/syslog/syslog.yaml

Each extension can run independently and send OTLP metrics to the same collector endpoint as ojo.

You can also run from each service folder:

cd services/docker && cargo run -- --config docker.yaml
cd services/gpu && cargo run -- --config gpu.yaml
cd services/sensors && cargo run -- --config sensors.yaml
cd services/mysql && cargo run -- --config mysql.yaml
cd services/postgres && cargo run -- --config postgres.yaml
cd services/nfs-client && cargo run -- --config nfs-client.yaml
cd services/nginx && cargo run -- --config nginx.yaml
cd services/redis && cargo run -- --config redis.yaml
cd services/systemd && cargo run -- --config systemd.yaml
cd services/systrace && cargo run -- --config systrace.yaml
cd services/syslog && cargo run -- --config syslog.yaml

3. Dump a snapshot for debugging

cargo run -- --config linux.yaml --dump-snapshot

Configuration

service:
  name: linux
  instance_id: linux-0001

collection:
  poll_interval_secs: 5
  include_process_metrics: true
  # Low-cardinality defaults for process labels.
  process_include_pid_label: false
  process_include_command_label: true
  process_include_state_label: true

export:
  otlp:
    endpoint: "http://127.0.0.1:4355/v1/metrics"
    protocol: http/protobuf
    compression: gzip
    timeout_secs: 10
  batch:
    interval_secs: 5
    timeout_secs: 10

Metric Selection

If metrics is omitted, all metrics are exported.

metrics:
  include: [system., process.]
  exclude: [process.linux.]

Rules:

• include and exclude are prefix-based
• exclude wins over include
• an empty include means include all metrics

Extension naming guidance:

• Docker metrics use system.docker.*
• GPU metrics use system.gpu.*
• Sensor metrics use system.sensor.*
• MySQL metrics use system.mysql.*
• Postgres metrics use system.postgres.*
• NFS client metrics use system.nfs_client.*
• NGINX metrics use system.nginx.*
• Redis metrics use system.redis.*
• Systemd metrics use system.systemd.*
• Systrace metrics use system.systrace.*
• Syslog metrics use system.syslog.*
• Keep custom extensions under system.* / process.* to preserve QA naming contracts

Environment Variables

Variable	Description
PROC_OTEL_CONFIG	Config file path override
PROC_POLL_INTERVAL_SECS	Poll interval override
PROC_INCLUDE_PROCESS_METRICS	Enable process metrics
PROC_PROCESS_INCLUDE_PID_LABEL	Include process.pid attribute on per-process metrics
PROC_PROCESS_INCLUDE_COMMAND_LABEL	Include process.command attribute on per-process metrics
PROC_PROCESS_INCLUDE_STATE_LABEL	Include process.state attribute on per-process metrics
OTEL_EXPORTER_OTLP_ENDPOINT	OTLP endpoint
OTEL_EXPORTER_OTLP_PROTOCOL	OTLP protocol
OTEL_EXPORTER_OTLP_HEADERS	OTLP headers
OTEL_EXPORTER_OTLP_COMPRESSION	OTLP compression
OTEL_EXPORTER_OTLP_TIMEOUT	OTLP timeout

OpenTelemetry Collector

A sample collector config is included in otel.yaml.

1. Start the collector
2. Point export.otlp.endpoint to its OTLP endpoint
3. Run Ojo and any extension sidecars you need

Suggested deployment patterns:

• Single host: run ojo + optional sidecars directly on the host
• Containerized host monitoring: run one sidecar per host domain (docker/gpu/sensors/mysql/postgres/nfs-client/nginx/redis/systemd/systrace/syslog)
• Centralized backend: route all producers through the same OTel Collector

Docker QA

docker compose -f docker.dev/docker-compose.yml run --rm qa-ubuntu-2204

docker compose up -d
# if you want to run all the containers

Build and Release

Release details, artifact matrix, and download/run examples are in DEPLOYMENT.md.

Build and Validate

cargo check
cargo check --workspace
cargo check --workspace --target x86_64-pc-windows-gnu
cargo test
cargo test --test qa_extension_metric_contracts
cargo llvm-cov -p host-collectors --all-features --summary-only --fail-under-lines 100

Cross-checking to x86_64-pc-windows-gnu from Linux requires a MinGW toolchain (e.g. Debian/Ubuntu: sudo apt-get install gcc-mingw-w64-x86-64) so crates like ring can compile C code for the Windows target.

Platform Notes

• Linux-only metrics are omitted on Windows by design
• Unsupported metrics are omitted rather than zeroed
• Windows uses windows.load.synthetic.* instead of Linux loadavg
• Windows process handle count is mapped for open-file-descriptor compatibility

Troubleshooting

No metrics exported

• Verify endpoint and protocol match your backend (grpc vs http/protobuf)
• Check collector or backend availability
• Enable debug logging: RUST_LOG=debug cargo run -- --config linux.yaml

Process metrics missing

• Ensure collection.include_process_metrics: true
• Verify process permissions
• Check that metrics filters are not excluding process.