Ilmar Kerm

Oracle, databases, Linux and maybe more

Archives: Exporting Oracle Rest Data Services metrics for Prometheus

Tested with ORDS 24.3 running using GraalVM 21.

ORDS documentation has a chapter how to push ORDS metrics to OpenTelemetry endpoint, which also is supported by Prometheus. But Prometheus traditionally is using the opposite method, that Prometheus itself will regularly connect to monitored service endpoints and scrape all its metrics. Similar JavaAgent method can also be deployed to expose ORDS metrics as a traditional Prometheus pull based endpoint.

For this we need to deploy Prometheus JMX exporter as a Java agent in ORDS, this will expose /metrics endpoint that Prometheus can scrape.

First, JMX exporter downloads and documentation is available here.

# Download JMX exporter to ORDS host
curl -o jmx_prometheus_javaagent.jar "https://repo1.maven.org/maven2/io/prometheus/jmx/jmx_prometheus_javaagent/1.0.1/jmx_prometheus_javaagent-1.0.1.jar"

Create configuration file, config.yaml with the following contents. It will format the JMX data into more usable Prometheus metric names.

rules:
    # Reformatting Oracle UCP metrics to have more usable names and adding data types
    - pattern: "oracle.ucp.admin.UniversalConnectionPoolMBean<name=.+, poolName=\\|(.+)\\|(.+)\\|.+><>connectionsClosedCount"
      name: oracle_ucp_connectionsClosedCount
      type: COUNTER
      labels:
          poolName: $1_$2
    - pattern: "oracle.ucp.admin.UniversalConnectionPoolMBean<name=.+, poolName=\\|(.+)\\|(.+)\\|.+><>connectionsCreatedCount"
      name: oracle_ucp_connectionsCreatedCount
      type: COUNTER
      labels:
          poolName: $1_$2
    - pattern: "oracle.ucp.admin.UniversalConnectionPoolMBean<name=.+, poolName=\\|(.+)\\|(.+)\\|.+><>cumulative(\\w+)"
      name: oracle_ucp_cumulative$3
      type: COUNTER
      labels:
          poolName: $1_$2
    - pattern: "oracle.ucp.admin.UniversalConnectionPoolMBean<name=.+, poolName=\\|(.+)\\|(.+)\\|.+><>(\\w+)"
      name: oracle_ucp_$3
      type: GAUGE
      labels:
          poolName: $1_$2
    # This pattern below will add all the rest, tons of detailed java internal things
    # Comment out if you do not want to see them
    - pattern: '.*'

I will assume, that jmx_prometheus_javaagent.jar and config.yaml are placed under /home/ords

Next, change ORDS startup script so it would include the JMX agent. The easiest way is to use environment variable _JAVA_OPTIONS for it.

# Set Startup Java options
# 10.10.10.10 is my local server IP where metrics exporter will bind to, default is localhost
# 21022 is the port JMX exporter will listen to
# With this ORDS metrics would be exposed as http://10.10.10.10:21022/metrics

export _JAVA_OPTIONS="-javaagent:/home/ords/jmx_prometheus_javaagent.jar=10.10.10.10:21022:/home/ords/config.yaml"

# Start ORDS in standalone mode as usual
ords serve

Below is my full ORDS SystemD service file – /etc/systemd/system/ords.service

[Unit]
Description=Oracle Rest Data Services
After=syslog.target network.target

[Service]
Type=simple
User=ords
Group=ords
Restart=always
RestartSec=30
Environment="_JAVA_OPTIONS=-Xms3G -Xmx3G -javaagent:/home/ords/jmx_prometheus_javaagent.jar=10.10.10.10:21022:/home/ords/config.yaml"
Environment="JAVA_HOME=/home/ords/graalvm"
#Environment="JAVA_TOOL_OPTIONS=-Djava.util.logging.config.file=/home/ords/logging.conf"
ExecStart=/home/ords/ords/bin/ords --config /etc/ords/config serve --secure --port 8443 --key /etc/ords/server.key --certificate /etc/ords/server.pem

[Install]
WantedBy=multi-user.target

After restarting ORDS I can query its metrics endpoint.

curl http://10.10.10.10:21022/metrics

# You will see many Java and JVM metrics in the output. Example...
jvm_memory_pool_max_bytes{pool="Compressed Class Space"} 1.073741824E9
jvm_memory_pool_max_bytes{pool="G1 Eden Space"} -1.0
jvm_memory_pool_max_bytes{pool="G1 Old Gen"} 3.221225472E9
jvm_memory_pool_max_bytes{pool="G1 Survivor Space"} -1.0
jvm_memory_pool_max_bytes{pool="Metaspace"} -1.0
jvm_memory_pool_used_bytes{pool="CodeHeap 'non-nmethods'"} 1822336.0
jvm_memory_pool_used_bytes{pool="CodeHeap 'non-profiled nmethods'"} 5918080.0
jvm_memory_pool_used_bytes{pool="CodeHeap 'profiled nmethods'"} 2.3397888E7
jvm_memory_pool_used_bytes{pool="Compressed Class Space"} 7328848.0
jvm_memory_pool_used_bytes{pool="G1 Eden Space"} 2.57949696E8
jvm_memory_pool_used_bytes{pool="G1 Old Gen"} 2.280663304E9
jvm_memory_pool_used_bytes{pool="G1 Survivor Space"} 8528.0
jvm_memory_pool_used_bytes{pool="Metaspace"} 6.750048E7
jvm_memory_used_bytes{area="heap"} 2.538621528E9
jvm_memory_used_bytes{area="nonheap"} 1.05967632E8
jvm_threads_deadlocked_monitor 0.0
jvm_threads_peak 62.0
jvm_threads_started_total 62.0
jvm_threads_state{state="BLOCKED"} 0.0
jvm_threads_state{state="NEW"} 0.0
jvm_threads_state{state="RUNNABLE"} 12.0
jvm_threads_state{state="TERMINATED"} 0.0
jvm_threads_state{state="TIMED_WAITING"} 20.0
jvm_threads_state{state="UNKNOWN"} 0.0
jvm_threads_state{state="WAITING"} 15.0

# ORDS database connection pool metrics will be exported like this
# Just an example... all UCP attributes are exported, for all ORDS connection pools

oracle_ucp_abandonedConnectionTimeout{poolName="backoffice_lo"} 0.0
oracle_ucp_abandonedConnectionTimeout{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_abandonedConnectionsCount{poolName="backoffice_lo"} 0.0
oracle_ucp_abandonedConnectionsCount{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_availableConnectionsCount{poolName="backoffice_lo"} 10.0
oracle_ucp_availableConnectionsCount{poolName="marketing_communications_2_lo"} 10.0
oracle_ucp_averageBorrowedConnectionsCount{poolName="backoffice_lo"} 1.0
oracle_ucp_averageBorrowedConnectionsCount{poolName="marketing_communications_2_lo"} 1.0
oracle_ucp_averageConnectionWaitTime{poolName="backoffice_lo"} 0.0
oracle_ucp_averageConnectionWaitTime{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_borrowedConnectionsCount{poolName="backoffice_lo"} 0.0
oracle_ucp_borrowedConnectionsCount{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_bufferSize{poolName="backoffice_lo"} 1024.0
oracle_ucp_bufferSize{poolName="marketing_communications_2_lo"} 1024.0
oracle_ucp_connectionHarvestMaxCount{poolName="backoffice_lo"} 1.0
oracle_ucp_connectionHarvestMaxCount{poolName="marketing_communications_2_lo"} 1.0
oracle_ucp_connectionHarvestTriggerCount{poolName="backoffice_lo"} 2.147483647E9
oracle_ucp_connectionHarvestTriggerCount{poolName="marketing_communications_2_lo"} 2.147483647E9
oracle_ucp_connectionRepurposeCount{poolName="backoffice_lo"} 0.0
oracle_ucp_connectionRepurposeCount{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_connectionValidationTimeout{poolName="backoffice_lo"} 15.0
oracle_ucp_connectionValidationTimeout{poolName="marketing_communications_2_lo"} 15.0
oracle_ucp_connectionWaitTimeout{poolName="backoffice_lo"} 3.0
oracle_ucp_connectionWaitTimeout{poolName="marketing_communications_2_lo"} 3.0
oracle_ucp_connectionsClosedCount{poolName="backoffice_lo"} 0.0
oracle_ucp_connectionsClosedCount{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_connectionsCreatedCount{poolName="backoffice_lo"} 10.0
oracle_ucp_connectionsCreatedCount{poolName="marketing_communications_2_lo"} 10.0
oracle_ucp_createConnectionInBorrowThread{poolName="backoffice_lo"} 1.0
oracle_ucp_createConnectionInBorrowThread{poolName="marketing_communications_2_lo"} 1.0
oracle_ucp_cumulativeConnectionBorrowedCount{poolName="backoffice_lo"} 1.0
oracle_ucp_cumulativeConnectionBorrowedCount{poolName="marketing_communications_2_lo"} 1.0
oracle_ucp_cumulativeConnectionReturnedCount{poolName="backoffice_lo"} 1.0
oracle_ucp_cumulativeConnectionReturnedCount{poolName="marketing_communications_2_lo"} 1.0
oracle_ucp_cumulativeConnectionUseTime{poolName="backoffice_lo"} 60.0
oracle_ucp_cumulativeConnectionUseTime{poolName="marketing_communications_2_lo"} 30.0
oracle_ucp_cumulativeConnectionWaitTime{poolName="backoffice_lo"} 0.0
oracle_ucp_cumulativeConnectionWaitTime{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_cumulativeFailedConnectionWaitCount{poolName="backoffice_lo"} 0.0
oracle_ucp_cumulativeFailedConnectionWaitCount{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_cumulativeFailedConnectionWaitTime{poolName="backoffice_lo"} 0.0
oracle_ucp_cumulativeFailedConnectionWaitTime{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_cumulativeSuccessfulConnectionWaitCount{poolName="backoffice_lo"} 0.0
oracle_ucp_cumulativeSuccessfulConnectionWaitCount{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_cumulativeSuccessfulConnectionWaitTime{poolName="backoffice_lo"} 0.0
oracle_ucp_cumulativeSuccessfulConnectionWaitTime{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_failedAffinityBasedBorrowCount{poolName="backoffice_lo"} 0.0
oracle_ucp_failedAffinityBasedBorrowCount{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_failedRCLBBasedBorrowCount{poolName="backoffice_lo"} 0.0
oracle_ucp_failedRCLBBasedBorrowCount{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_failoverEnabled{poolName="backoffice_lo"} 0.0
oracle_ucp_failoverEnabled{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_inactiveConnectionTimeout{poolName="backoffice_lo"} 1800.0
oracle_ucp_inactiveConnectionTimeout{poolName="marketing_communications_2_lo"} 1800.0
oracle_ucp_initialPoolSize{poolName="backoffice_lo"} 10.0
oracle_ucp_initialPoolSize{poolName="marketing_communications_2_lo"} 10.0
oracle_ucp_labeledConnectionsCount{poolName="backoffice_lo"} 0.0
oracle_ucp_labeledConnectionsCount{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_loggingEnabled{poolName="backoffice_lo"} 0.0
oracle_ucp_loggingEnabled{poolName="marketing_communications_2_lo"} 0.0
oracle_ucp_maxConnectionReuseCount{poolName="backoffice_lo"} 1000.0

Archives: ORDS+GraphQL with GraalVM 21, for DBAs

I’m forced to write my first JavaScript related post 🙁 Oh, well.

ORDS version at the time of writing is 24.3.

Oracle Rest Data Services (ORDS) does support (currently read-only) GraphQL protocol for serving data from Oracle rest enabled tables. You can read more about it here: https://oracle-base.com/articles/misc/oracle-rest-data-services-ords-graphql

To get GraphQL support working, ORDS need to be running using GraalVM JDK – but it’s not as simple as switching the JDK – GraalVM also needs to support JavaScript polyglot engine. When I started looking into this world I was properly confused, starting with naming – ORDS 24.3 installation checklist still requires GraalVM Enterprise Edition and when going to search for it find man-bear-pigs like GraalVM-EE-23-for-JDK-17. Properly confusing for a non-developer like me.

Luckily naming has been significantly simplified recently and GraalVM EE is dead

Naming starting from GraalVM for JDK21 is simplified, but what has gone much more complicated is installing JavaScript polyglot libraries for GraalVM. With GraalVM for JDK 17 there was a command “gu install” for it, but it has been removed starting from GraalVM for JDK 21.

ORDS installation checklist 24.3 acknowledges it, but then gives some strange XML code on how to install them. Not helpful for non-developers, like me. This XML is intended to describe dependencies for Java project (using Maven), so during build the dependencies would be fetched automatically. But I have nothing to build – GraphQL support is already in ORDS, I just need the dependencies downloaded.

I think, if the extra libraries are needed for ORDS built in functionality to work, ORDS should include them by default.

Installation steps

I know pretty much all software can be downloaded using Oracle provided yum repositories, but here I’m doing everything manually, to be able to control the versions precisely. And not to mess with RPM-s, unzipping this is so much easier and predictable and more usable across all possible Linux distributions.

All software is placed under /home/ords in my example.

First lets download GraalVM for JDK 21 itself. Oracle has started to offer non-website-clicking “script friendly” URLs that always point to the latest version, you can get them here. I’m not going to use ANY latest URL Oracle offers on purpose, since I’m an automation guy I need to be able to download predictable and internally tested versions of the software and be able to validate the downloaded software against known checksum value.

Download the software, all versions are current at the time of writing, but of course are very soon out of date

# GraalVM for JDK21
https://download.oracle.com/graalvm/21/archive/graalvm-jdk-21.0.5_linux-x64_bin.tar.gz

# Maven
https://dlcdn.apache.org/maven/maven-3/3.9.9/binaries/apache-maven-3.9.9-bin.tar.gz

# ORDS
https://download.oracle.com/otn_software/java/ords/ords-24.3.0.262.0924.zip

In Ansible something like this, also unzipping them. Take it as an example, and not copy it blindly

# Facts
graalvm_download_url: "https://download.oracle.com/graalvm/21/archive/graalvm-jdk-21.0.5_linux-x64_bin.tar.gz"
graalvm_download_checksum: "sha256:c1960d4f9d278458bde1cd15115ac2f0b3240cb427d51cfeceb79dab91a7f5c9"
graalvm_install_dir: "{{ ords_install_base }}/graalvm"

maven_download_url: "https://dlcdn.apache.org/maven/maven-3/3.9.9/binaries/apache-maven-3.9.9-bin.tar.gz"
maven_download_checksum: "sha512:a555254d6b53d267965a3404ecb14e53c3827c09c3b94b5678835887ab404556bfaf78dcfe03ba76fa2508649dca8531c74bca4d5846513522404d48e8c4ac8b"
maven_install_dir: "{{ ords_install_base }}/maven"

ords_download_url: "https://download.oracle.com/otn_software/java/ords/ords-24.3.0.262.0924.zip"
ords_installer_checksum: "sha1:6e8d9b15faa232911fcff367c99ba696389ceddc"
ords_install_dir: "{{ ords_install_base }}/ords"
ords_install_base: "/home/ords"

# Tasks
- name: Download GraalVM
  ansible.builtin.get_url:
      url: "{{ graalvm_download_url }}"
      dest: "{{ ords_install_base }}/graalvm.tar.gz"
      checksum: "{{ graalvm_download_checksum }}"
      use_proxy: "{{ 'yes' if http_proxy is defined and http_proxy else 'no' }}"
  environment:
      https_proxy: "{{ http_proxy }}"
  register: graalvm_downloaded
- name: Unzip GraalVM
  ansible.builtin.unarchive:
      remote_src: yes
      src: "{{ ords_install_base }}/graalvm.tar.gz"
      dest: "{{ graalvm_install_dir }}"
      extra_opts:
          - "--strip-components=1"
  when: graalvm_downloaded is changed
# Download maven
- name: Download Maven
  ansible.builtin.get_url:
      url: "{{ maven_download_url }}"
      dest: "{{ ords_install_base }}/maven.tar.gz"
      checksum: "{{ maven_download_checksum }}"
      use_proxy: "{{ 'yes' if http_proxy is defined and http_proxy else 'no' }}"
  environment:
      https_proxy: "{{ http_proxy }}"
  register: maven_downloaded
- name: Unzip maven
  ansible.builtin.unarchive:
      remote_src: yes
      src: "{{ ords_install_base }}/maven.tar.gz"
      dest: "{{ maven_install_dir }}"
      extra_opts:
          - "--strip-components=1"
  when: maven_downloaded is changed
# Download ORDS
- name: Download ORDS
  ansible.builtin.get_url:
      url: "{{ ords_download_url }}"
      dest: "{{ ords_install_base }}/ords-latest.zip"
      checksum: "{{ ords_installer_checksum }}"
      use_proxy: "{{ 'yes' if http_proxy is defined and http_proxy else 'no' }}"
  environment:
      https_proxy: "{{ http_proxy }}"
  register: ords_downloaded
- name: Unzip ORDS installer
  ansible.builtin.unarchive:
      remote_src: yes
      src: "{{ ords_install_base }}/ords-latest.zip"
      dest: "{{ ords_install_dir }}"
  when: ords_downloaded is changed

Now the complicated part, adding GraalVM JavaScript polyglot libraries

Create pom.xml file in some directory with contents. 24.1.1 is the current JavaScript engine version, you can see the available versions in https://mvnrepository.com/artifact/org.graalvm.polyglot/polyglot

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>eu.ilmarkerm.ords</groupId>
  <artifactId>ords-graaljs-download</artifactId>
  <version>1.1.1</version>
  <url>https://ilmarkerm.eu</url>
  <name>POM to download GraalVM JavaScript engine</name>
  <dependencies>
    <dependency>
        <groupId>org.graalvm.polyglot</groupId>
        <artifactId>polyglot</artifactId>
        <version>24.1.1</version>
    </dependency>
    <dependency>
        <groupId>org.graalvm.polyglot</groupId>
        <!-- Language: js -->
        <artifactId>js</artifactId>
        <version>24.1.1</version>
        <type>pom</type>
    </dependency>
  </dependencies>
</project>

Execute maven to download the required libraries and place them under ORDS libraries

/home/ords/maven/bin/mvn dependency:copy-dependencies -DoutputDirectory=/home/ords/ords/lib/ext -DuseBaseVersion=true

It will download files like these (polyglot 24.1.1):

collections-24.1.1.jar
icu4j-24.1.1.jar
jniutils-24.1.1.jar
js-language-24.1.1.jar
nativebridge-24.1.1.jar
nativeimage-24.1.1.jar
polyglot-24.1.1.jar
regex-24.1.1.jar
truffle-api-24.1.1.jar
truffle-compiler-24.1.1.jar
truffle-enterprise-24.1.1.jar
truffle-runtime-24.1.1.jar
word-24.1.1.jar

Start ORDS (using GraalVM JDK) and then ORDS support for GraphQL is ready to be used.

Conclusion

I’m not a java developer, so things might be wrong here 🙂

But I do hope the situation improves over the next couple of ORDS versions.

Categories

Ilmar Kerm