public final class MergeSchedulerConfig
extends java.lang.Object
ConcurrentMergeScheduler
) controls the execution of
merge operations once they are needed (according to the merge policy). Merges
run in separate threads, and when the maximum number of threads is reached,
further merges will wait until a merge thread becomes available.
The merge scheduler supports the following dynamic settings:
index.merge.scheduler.max_thread_count
:
The maximum number of threads that may be merging at once. Defaults to
Math.max(1, Math.min(4, Runtime.getRuntime().availableProcessors() / 2))
which works well for a good solid-state-disk (SSD). If your index is on
spinning platter drives instead, decrease this to 1.
index.merge.scheduler.auto_throttle
:
If this is true (the default), then the merge scheduler will rate-limit IO
(writes) for merges to an adaptive value depending on how many merges are
requested over time. An application with a low indexing rate that
unluckily suddenly requires a large merge will see that merge aggressively
throttled, while an application doing heavy indexing will see the throttle
move higher to allow merges to keep up with ongoing indexing.
Modifier and Type | Field and Description |
---|---|
static Setting<java.lang.Boolean> |
AUTO_THROTTLE_SETTING |
static Setting<java.lang.Integer> |
MAX_MERGE_COUNT_SETTING |
static Setting<java.lang.Integer> |
MAX_THREAD_COUNT_SETTING |
Modifier and Type | Method and Description |
---|---|
int |
getMaxMergeCount()
Returns
maxMergeCount . |
int |
getMaxThreadCount()
Returns
maxThreadCount . |
boolean |
isAutoThrottle()
Returns
true iff auto throttle is enabled. |
public static final Setting<java.lang.Integer> MAX_THREAD_COUNT_SETTING
public static final Setting<java.lang.Integer> MAX_MERGE_COUNT_SETTING
public static final Setting<java.lang.Boolean> AUTO_THROTTLE_SETTING
public boolean isAutoThrottle()
true
iff auto throttle is enabled.ConcurrentMergeScheduler.enableAutoIOThrottle()
public int getMaxThreadCount()
maxThreadCount
.public int getMaxMergeCount()
maxMergeCount
.