com.google.cloud.spanner

Class SessionPoolOptions.Builder

java.lang.Object

com.google.cloud.spanner.SessionPoolOptions.Builder

Enclosing class:

SessionPoolOptions

public static class SessionPoolOptions.Builder
extends Object

Builder for creating SessionPoolOptions.

Constructor Summary

Constructors

Constructor and Description
Builder()

Method Summary

Modifier and Type	Method and Description
SessionPoolOptions	build() Build a SessionPoolOption object
SessionPoolOptions.Builder	setBlockIfPoolExhausted() If all sessions are in use and there is no more room for creating new sessions, block for a session to become available.
SessionPoolOptions.Builder	setFailIfPoolExhausted() If all sessions are in use and and maxSessions has been reached, fail the request by throwing a SpannerException with the error code RESOURCE_EXHAUSTED.
SessionPoolOptions.Builder	setKeepAliveIntervalMinutes(int intervalMinutes) How frequently to keep alive idle sessions.
SessionPoolOptions.Builder	setMaxIdleSessions(int maxIdleSessions) Maximum number of idle sessions that this pool will maintain.
SessionPoolOptions.Builder	setMaxSessions(int maxSessions) Maximum number of sessions that this pool will have.
SessionPoolOptions.Builder	setMinSessions(int minSessions) Minimum number of sessions that this pool will always maintain.
SessionPoolOptions.Builder	setWriteSessionsFraction(float writeSessionsFraction) Fraction of sessions to be kept prepared for write transactions.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Builder

public Builder()

Method Detail

setMinSessions

public SessionPoolOptions.Builder setMinSessions(int minSessions)

Minimum number of sessions that this pool will always maintain. These will be created eagerly in parallel. Defaults to 0.

setMaxSessions

public SessionPoolOptions.Builder setMaxSessions(int maxSessions)

Maximum number of sessions that this pool will have. If current numbers of sessions in the pool is less than this and they are all busy, then a new session will be created for any new operation. If current number of in use sessions is same as this and a new request comes, pool can either block or fail. Defaults to 400.

setMaxIdleSessions

public SessionPoolOptions.Builder setMaxIdleSessions(int maxIdleSessions)

Maximum number of idle sessions that this pool will maintain. Pool will close any sessions beyond this but making sure to always have at least as many sessions as specified by setMinSessions(int). To determine how many sessions are idle we look at maximum number of sessions used concurrently over a window of time. Any sessions beyond that are idle. Defaults to 0.

setKeepAliveIntervalMinutes

public SessionPoolOptions.Builder setKeepAliveIntervalMinutes(int intervalMinutes)

How frequently to keep alive idle sessions. This should be less than 60 since an idle session is automatically closed after 60 minutes. Sessions will be kept alive by sending a dummy query "Select 1". Default value is 30 minutes.

setFailIfPoolExhausted

public SessionPoolOptions.Builder setFailIfPoolExhausted()

If all sessions are in use and and maxSessions has been reached, fail the request by throwing a SpannerException with the error code RESOURCE_EXHAUSTED. Default behavior is to block the request.

setBlockIfPoolExhausted

public SessionPoolOptions.Builder setBlockIfPoolExhausted()

If all sessions are in use and there is no more room for creating new sessions, block for a session to become available. Default behavior is same.

setWriteSessionsFraction

public SessionPoolOptions.Builder setWriteSessionsFraction(float writeSessionsFraction)

Fraction of sessions to be kept prepared for write transactions. This is an optimisation to avoid the cost of sending a BeginTransaction() rpc. If all such sessions are in use and a write request comes, we will make the BeginTransaction() rpc inline. It must be between 0 and 1(inclusive).

Default value is 0.2.

build

public SessionPoolOptions build()

Build a SessionPoolOption object