Configuring and tuning orchestration
After installing PE, you can change some default settings to further configure the orchestrator and pe-orchestration-services.
Configure the orchestrator and pe-orchestration-services
There are several optional parameters you can add to configure the behavior of the orchestrator and pe-orchestration-services. Because they are profile classes, you can change these in the console in the PE Orchestrator group.
- Disable or enable the PXP service by setting it to
false. If you disable this setting you can’t use the orchestrator or the Run Puppet button in the console.
- An integer that determines the maximum number of concurrent requests orchestrator can make to bolt-server.
- Default: The current value stored for the Bolt server.
CAUTION: Do not set a concurrency limit that is higher than the bolt-server limit. This can cause timeouts that lead to failed task runs.
- An integer that determines how many concurrent compile requests can be outstanding to the master, across all orchestrator jobs.
- Integer that represents the number of days before job reports are removed.
- An integer that represents how many seconds should pass while an agent attempts to connect to a PCP broker. If the agent can’t connect to the broker in that time frame, the run times out.
- Disable or enable orchestration services. Set to
- Integer representing the number of tasks that can run at the same time.
- Enable or disable application management. Set to
Configure the PXP agent
Puppet Execution Protocol (PXP) is a messaging system used to request tasks and communicate task statuses. ThePXP agent runs the PXP service and you can configure it using Hiera.
- Controls how frequently (in seconds) PXP agents will ping PCP brokers. If the brokers don’t respond, the agents try to reconnect.
- A string that represents the path to the PXP agent log file and can be used to debug issues with orchestrator.
- The amount of time to keep records of old Puppet or task runs on agents. You can declare time in minutes (30m), hours (2h), and days (14d).
- Controls how long tasks should be cached after use. You can declare time in minutes (30m), hours (2h), and days (14d).
Correct ARP table overflow
In larger deployments that use the PCP broker, you might encounter ARP table overflows and need to adjust some system settings.
Overflows occur when the ARP table—a local cache of IP address to MAC address resolutions—fills and starts evicting old entries. When frequently used entries are evicted, network traffic will increase to restore them, increasing network latency and CPU load on the broker.
A typical log message looks like:
[root@s1 peadmin]# tail -f /var/log/messages Aug 10 22:42:36 s1 kernel: Neighbour table overflow. Aug 10 22:42:36 s1 kernel: Neighbour table overflow. Aug 10 22:42:36 s1 kernel: Neighbour table overflow.
To work around this issue:
# Set max table size net.ipv6.neigh.default.gc_thresh3=4096 net.ipv4.neigh.default.gc_thresh3=4096 # Start aggressively clearing the table at this threshold net.ipv6.neigh.default.gc_thresh2=2048 net.ipv4.neigh.default.gc_thresh2=2048 # Don't clear any entries until this threshold net.ipv6.neigh.default.gc_thresh1=1024 net.ipv4.neigh.default.gc_thresh1=1024