Tuner (Javadocs [I2P+ 2.13.0+] - API Version 0.9.70+)

java.lang.Object
- net.i2p.util.SimpleTimer2.TimedEvent
- - net.i2p.router.Tuner

All Implemented Interfaces:
Runnable
```
public class Tuner
extends SimpleTimer2.TimedEvent
```
General-purpose adaptive tuner. Observes network and system stats, adjusts tunable parameters to optimize router performance.
Runs every 30 seconds via SimpleTimer2. Each parameter implements an AIMD-style feedback loop bounded within safe ranges:
1. Read observed stat (60s rolling average)
2. Compute target value from observed stat + cross-references
3. Clamp target to [min, max]
4. Apply health-based dampening when system is degraded
5. Accelerate rollback when param diverges from default
6. Call applyValue() to push the new value to the router
New parameters are added by extending Tuner.BaseParam and implementing:
- applyValue(int) — push value to router subsystem
- getRuntimeValue() — read current value from subsystem
- getObservedStat(RouterContext) — read primary signal
- computeTarget(double) — feedback logic with cross-refs
Params can be tuned live via the console UI or persisted to autotune.config (separate from router.config). Auto-revert to factory defaults triggers when system health drops below 0.3.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`Tuner.AutotuneConfig` Manages the autotune.config file — separate from router.config.
`(package private) static class`	`Tuner.BaseParam` Base class for tunable params with history tracking and auto-revert.
`static class`	`Tuner.ParamSnapshot` Snapshot of a subsystem's tunable parameter values at a point in time.
`static class`	`Tuner.SubsystemScore` Per-subsystem health scores.
`(package private) static class`	`Tuner.SystemHealth` Tracks overall router health score for adaptive tuning decisions.
`static interface`	`Tuner.TunableParam` A tunable parameter with name, description, bounds, and default value.

Field Summary

Fields
Modifier and Type	Field and Description
`(package private) static int`	`MAX_HISTORY` Max history samples for sparklines (30 samples @ 30s = 15min)
`(package private) static String`	`PROP_PREFIX` Property prefix for tuner ranges.
`(package private) static long`	`STAT_PERIOD` Period for short-term bandwidth stats.
`(package private) static long`	`STAT_PERIOD_LONG` Period for long-term bandwidth stats.
`static String`	`SUB_CONGESTION` Congestion subsystem identifier.
`static String`	`SUB_CRYPTO` Crypto subsystem identifier.
`static String`	`SUB_I2CP` I2CP subsystem identifier.
`static String`	`SUB_NETDB` NetDB subsystem identifier.
`static String`	`SUB_PEER` Peers subsystem identifier.
`static String`	`SUB_ROUTER` Router subsystem identifier.
`static String`	`SUB_STREAMING` Streaming subsystem identifier.
`static String`	`SUB_TRANSIT` Transit subsystem identifier.
`static String`	`SUB_TRANSPORT` Subsystem labels for grouping in the UI
`static String`	`SUB_TUNNEL` Tunnel subsystem identifier.

Fields inherited from class net.i2p.util.SimpleTimer2.TimedEvent
_state, DEFAULT_FUZZ

Constructor Summary
Constructors
Constructor and Description
Tuner(RouterContext ctx)
Set up the tuner with all tunable parameters.

Constructors
Constructor and Description
`Tuner(RouterContext ctx)` Set up the tuner with all tunable parameters.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static void`	`adjustHandlerPriority()` Adjust the current thread's priority to the target handler priority.
`Tuner.AutotuneConfig`	`getAutotune()` Shared AutotuneConfig instance.
`static int`	`getBuildFailureBuffer()` The build failure buffer.
`static int`	`getHandlerThreadPriority()` The handler thread priority.
`double`	`getHealthScore()` Latest system health score (0.0 = worst, 1.0 = perfect).
`static int`	`getInternalQueueSize()` The I2CP internal queue size.
`static int`	`getMaxDispatchAgeMs()` The max dispatch age in ms.
`(package private) static double`	`getMemoryPressure()` Returns current heap memory pressure as a ratio from 0.0 (no pressure) to 1.0 (heap full).
`Tuner.TunableParam`	`getParam(String name)` Tunable param by name.
`List<Tuner.ParamSnapshot>`	`getSnapshots()` Snapshots of all tunable params.
`List<Tuner.SubsystemScore>`	`getSubsystemScores()` Per-subsystem health scores computed during the last tuning cycle.
`static int`	`getTestClientBudget()` The test client budget.
`static int`	`getTestRetestBackoff()` The test retest backoff.
`void`	`restoreDefaults()` Restore all params to factory defaults (code-level, not persisted)
`(package private) static int`	`scaleForSystem(int base, int hardMin, int hardMax)` Compute a system-scaled value: base * factor, bounded by min and max.
`static void`	`setInternalQueueSize(int size)` Set the I2CP internal queue size (called by Tuner).
`void`	`setOverride(String name, int value)` Set an override value for a param.
`void`	`shutdown()` Flush on shutdown — unconditional write if dirty
`void`	`timeReached()` Expire entries and reschedule the next check.

Methods inherited from class net.i2p.util.SimpleTimer2.TimedEvent
cancel, forceReschedule, reschedule, reschedule, run, schedule, setFuzz, setPool, toString

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - MAX_HISTORY
```
static final int MAX_HISTORY
```
    Max history samples for sparklines (30 samples @ 30s = 15min)
    See Also:
    Constant Field Values
  - PROP_PREFIX
```
static final String PROP_PREFIX
```
    Property prefix for tuner ranges. Format: tuner.{paramName}.min, tuner.{paramName}.max, tuner.{paramName}.step
    See Also:
    Constant Field Values
  - STAT_PERIOD
```
static final long STAT_PERIOD
```
    Period for short-term bandwidth stats.
    See Also:
    Constant Field Values
  - STAT_PERIOD_LONG
```
static final long STAT_PERIOD_LONG
```
    Period for long-term bandwidth stats.
    See Also:
    Constant Field Values
  - SUB_CONGESTION
```
public static final String SUB_CONGESTION
```
    Congestion subsystem identifier.
    See Also:
    Constant Field Values
  - SUB_CRYPTO
```
public static final String SUB_CRYPTO
```
    Crypto subsystem identifier.
    See Also:
    Constant Field Values
  - SUB_I2CP
```
public static final String SUB_I2CP
```
    I2CP subsystem identifier.
    See Also:
    Constant Field Values
  - SUB_NETDB
```
public static final String SUB_NETDB
```
    NetDB subsystem identifier.
    See Also:
    Constant Field Values
  - SUB_PEER
```
public static final String SUB_PEER
```
    Peers subsystem identifier.
    See Also:
    Constant Field Values
  - SUB_ROUTER
```
public static final String SUB_ROUTER
```
    Router subsystem identifier.
    See Also:
    Constant Field Values
  - SUB_STREAMING
```
public static final String SUB_STREAMING
```
    Streaming subsystem identifier.
    See Also:
    Constant Field Values
  - SUB_TRANSIT
```
public static final String SUB_TRANSIT
```
    Transit subsystem identifier.
    See Also:
    Constant Field Values
  - SUB_TRANSPORT
```
public static final String SUB_TRANSPORT
```
    Subsystem labels for grouping in the UI
    See Also:
    Constant Field Values
  - SUB_TUNNEL
```
public static final String SUB_TUNNEL
```
    Tunnel subsystem identifier.
    See Also:
    Constant Field Values
- Constructor Detail
  - Tuner
```
public Tuner(RouterContext ctx)
```
    Set up the tuner with all tunable parameters.
    Parameters:
    ctx - the router context
- Method Detail
  - adjustHandlerPriority
```
public static void adjustHandlerPriority()
```
    Adjust the current thread's priority to the target handler priority. Call this from handler thread main loops — lightweight volatile read. Critical threads (watchdog, event pumper, job queue) should NOT call this.
  - getAutotune
```
public Tuner.AutotuneConfig getAutotune()
```
    Shared AutotuneConfig instance. Form handlers should use this (not new AutotuneConfig()) so writes go to the same in-memory instance the Tuner reads from.
    Returns:
    the autotune config
  - getBuildFailureBuffer
```
public static int getBuildFailureBuffer()
```
    The build failure buffer.
    Returns:
    the build failure buffer
  - getHandlerThreadPriority
```
public static int getHandlerThreadPriority()
```
    The handler thread priority.
    Returns:
    the target priority for I/O handler threads
  - getHealthScore
```
public double getHealthScore()
```
    Latest system health score (0.0 = worst, 1.0 = perfect). Returns NaN if health hasn't been computed yet.
    Returns:
    the health score
  - getInternalQueueSize
```
public static int getInternalQueueSize()
```
    The I2CP internal queue size.
    Returns:
    the current I2CP internal queue size
  - getMaxDispatchAgeMs
```
public static int getMaxDispatchAgeMs()
```
    The max dispatch age in ms.
    Returns:
    the max dispatch age in ms
  - getMemoryPressure
```
static double getMemoryPressure()
```
    Returns current heap memory pressure as a ratio from 0.0 (no pressure) to 1.0 (heap full). Used to scale cache sizes and buffer pools.
  - getParam
```
public Tuner.TunableParam getParam(String name)
```
    Tunable param by name.
    Parameters:
    name - the param name
    Returns:
    the param or null
  - getSnapshots
```
public List<Tuner.ParamSnapshot> getSnapshots()
```
    Snapshots of all tunable params.
    Returns:
    list of param snapshots
  - getSubsystemScores
```
public List<Tuner.SubsystemScore> getSubsystemScores()
```
    Per-subsystem health scores computed during the last tuning cycle. Returns a list of SubsystemScore sorted by the SUBSYSTEM_ORDER used on the tuning page.
    Returns:
    list of subsystem scores
  - getTestClientBudget
```
public static int getTestClientBudget()
```
    The test client budget.
    Returns:
    the test client budget
  - getTestRetestBackoff
```
public static int getTestRetestBackoff()
```
    The test retest backoff.
    Returns:
    the test retest backoff
  - restoreDefaults
```
public void restoreDefaults()
```
    Restore all params to factory defaults (code-level, not persisted)
  - scaleForSystem
```
static int scaleForSystem(int base,
                          int hardMin,
                          int hardMax)
```
    Compute a system-scaled value: base * factor, bounded by min and max. Factor is max(memFactor, coreFactor), halved for slow systems.
  - setInternalQueueSize
```
public static void setInternalQueueSize(int size)
```
    Set the I2CP internal queue size (called by Tuner).
    Parameters:
    size - the queue size
  - setOverride
```
public void setOverride(String name,
                        int value)
```
    Set an override value for a param.
    Parameters:
    name - the param name
    value - the override value
  - shutdown
```
public void shutdown()
```
    Flush on shutdown — unconditional write if dirty
  - timeReached
```
public void timeReached()
```
    Expire entries and reschedule the next check.
    Specified by:
    timeReached in class SimpleTimer2.TimedEvent

Class Tuner

Nested Class Summary

Field Summary

Fields inherited from class net.i2p.util.SimpleTimer2.TimedEvent

Constructor Summary

Method Summary

Methods inherited from class net.i2p.util.SimpleTimer2.TimedEvent

Methods inherited from class java.lang.Object

Field Detail

MAX_HISTORY

PROP_PREFIX

STAT_PERIOD

STAT_PERIOD_LONG

SUB_CONGESTION

SUB_CRYPTO

SUB_I2CP

SUB_NETDB

SUB_PEER

SUB_ROUTER

SUB_STREAMING

SUB_TRANSIT

SUB_TRANSPORT

SUB_TUNNEL

Constructor Detail

Tuner

Method Detail

adjustHandlerPriority

getAutotune

getBuildFailureBuffer

getHandlerThreadPriority

getHealthScore

getInternalQueueSize

getMaxDispatchAgeMs

getMemoryPressure

getParam

getSnapshots

getSubsystemScores

getTestClientBudget

getTestRetestBackoff

restoreDefaults

scaleForSystem

setInternalQueueSize

setOverride

shutdown

timeReached