Key | Default | Type | Description
--- | --- | --- | ---

##### pekko.ask.callstack

true

Boolean

If true, call stack for asynchronous asks are captured. That way, when an ask fails (for example times out), you get a proper exception, describing to the original method call and call site. Note that in case of having millions of concurrent RPC calls, this may add to the memory footprint.

##### pekko.ask.timeout

10 s

Duration

Timeout used for all futures and blocking Pekko calls. If Flink fails due to timeouts then you should try to increase this value. Timeouts can be caused by slow machines or a congested network. The timeout value requires a time-unit specifier (ms/s/min/h/d).

##### pekko.client-socket-worker-pool.pool-size-factor

1.0

Double

The pool size factor is used to determine thread pool size using the following formula: ceil(available processors * factor). Resulting size is then bounded by the pool-size-min and pool-size-max values.

##### pekko.client-socket-worker-pool.pool-size-max

2

Integer

Max number of threads to cap factor-based number to.

##### pekko.client-socket-worker-pool.pool-size-min

1

Integer

Min number of threads to cap factor-based number to.

##### pekko.fork-join-executor.parallelism-factor

2.0

Double

The parallelism factor is used to determine thread pool size using the following formula: ceil(available processors * factor). Resulting size is then bounded by the parallelism-min and parallelism-max values.

##### pekko.fork-join-executor.parallelism-max

64

Integer

Max number of threads to cap factor-based parallelism number to.

##### pekko.fork-join-executor.parallelism-min

8

Integer

Min number of threads to cap factor-based parallelism number to.

##### pekko.framesize

"10485760b"

String

Maximum size of messages which are sent between the JobManager and the TaskManagers. If Flink fails because messages exceed this limit, then you should increase it. The message size requires a size-unit specifier.

##### pekko.jvm-exit-on-fatal-error

true

Boolean

Exit JVM on fatal Pekko errors.

##### pekko.log.lifecycle.events

false

Boolean

Turns on the Pekko’s remote logging of events. Set this value to 'true' in case of debugging.

##### pekko.lookup.timeout

10 s

Duration

Timeout used for the lookup of the JobManager. The timeout value has to contain a time-unit specifier (ms/s/min/h/d).

##### pekko.remote-fork-join-executor.parallelism-factor

2.0

Double

The parallelism factor is used to determine thread pool size using the following formula: ceil(available processors * factor). Resulting size is then bounded by the parallelism-min and parallelism-max values.

##### pekko.remote-fork-join-executor.parallelism-max

16

Integer

Max number of threads to cap factor-based parallelism number to.

##### pekko.remote-fork-join-executor.parallelism-min

8

Integer

Min number of threads to cap factor-based parallelism number to.

##### pekko.retry-gate-closed-for

50

Long

Milliseconds a gate should be closed for after a remote connection was disconnected.

##### pekko.server-socket-worker-pool.pool-size-factor

1.0

Double

The pool size factor is used to determine thread pool size using the following formula: ceil(available processors * factor). Resulting size is then bounded by the pool-size-min and pool-size-max values.

##### pekko.server-socket-worker-pool.pool-size-max

2

Integer

Max number of threads to cap factor-based number to.

##### pekko.server-socket-worker-pool.pool-size-min

1

Integer

Min number of threads to cap factor-based number to.

##### pekko.ssl.enabled

true

Boolean

Turns on SSL for Pekko’s remote communication. This is applicable only when the global ssl flag security.ssl.enabled is set to true.

##### pekko.startup-timeout

(none)

Duration

Timeout after which the startup of a remote component is considered being failed.

##### pekko.tcp.timeout

20 s

Duration

Timeout for all outbound connections. If you should experience problems with connecting to a TaskManager due to a slow network, you should increase this value.

##### pekko.throughput

15

Integer

Number of messages that are processed in a batch before returning the thread to the pool. Low values denote a fair scheduling whereas high values can increase the performance at the cost of unfairness.