public interface ResourceManager
Cache
.
Re-balancing the GemFire Cache resources can be accomplished using a RebalanceOperation
:
ResourceManager resourceManager = cache.getResourceManager(); RebalanceOperation rebalanceOp = resourceManager.createRebalanceFactory().start();Monitoring of heap utilization is enabled by setting the critical heap percentage using
setCriticalHeapPercentage(float)
.Modifier and Type | Field and Description |
---|---|
static float |
DEFAULT_CRITICAL_PERCENTAGE
The default percent of heap memory at which the VM is considered in a critical state.
|
static float |
DEFAULT_EVICTION_PERCENTAGE
The default percent of heap memory at which the VM should begin evicting data.
|
Modifier and Type | Method and Description |
---|---|
RebalanceFactory |
createRebalanceFactory()
Creates a factory for defining and starting
RebalanceOperations . |
RestoreRedundancyOperation |
createRestoreRedundancyOperation()
Creates a
RestoreRedundancyOperation class for defining and starting restore redundancy
operations and for determining the redundancy status of regions. |
float |
getCriticalHeapPercentage()
Get the percentage of heap at or above which the cache is considered in danger of becoming
inoperable.
|
float |
getCriticalOffHeapPercentage()
Get the percentage of off-heap at or above which the cache is considered in danger of becoming
inoperable.
|
float |
getEvictionHeapPercentage()
Get the percentage of heap at or above which the eviction should begin on Regions configured
for HeapLRU eviction.
|
float |
getEvictionOffHeapPercentage()
Get the percentage of off-heap at or above which the eviction should begin on Regions
configured for HeapLRU eviction.
|
Set<RebalanceOperation> |
getRebalanceOperations()
Returns a set of all active
RebalanceOperations that were started
locally on this member. |
Set<CompletableFuture<RestoreRedundancyResults>> |
getRestoreRedundancyFutures()
Returns a set of all active restore redundancy futures that were started locally on this
member.
|
void |
setCriticalHeapPercentage(float heapPercentage)
Set the percentage of heap at or above which the cache is considered in danger of becoming
inoperable due to garbage collection pauses or out of memory exceptions.
|
void |
setCriticalOffHeapPercentage(float offHeapPercentage)
Set the percentage of off-heap at or above which the cache is considered in danger of becoming
inoperable due to out of memory exceptions.
|
void |
setEvictionHeapPercentage(float heapPercentage)
Set the percentage of heap at or above which the eviction should begin on Regions configured
for HeapLRU eviction.
|
void |
setEvictionOffHeapPercentage(float offHeapPercentage)
Set the percentage of off-heap at or above which the eviction should begin on Regions
configured for HeapLRU eviction.
|
static final float DEFAULT_CRITICAL_PERCENTAGE
0.0
.static final float DEFAULT_EVICTION_PERCENTAGE
0.0
. Note that if a HeapLRU is created and the eviction heap percentage has not
been set then it will default 80.0
unless the critical heap percentage has been
set in which case it will default to a value 5.0
less than the critical heap
percentage.RebalanceFactory createRebalanceFactory()
RebalanceOperations
.Set<RebalanceOperation> getRebalanceOperations()
RebalanceOperations
that were started
locally on this member.RestoreRedundancyOperation createRestoreRedundancyOperation()
RestoreRedundancyOperation
class for defining and starting restore redundancy
operations and for determining the redundancy status of regions. Similar to a rebalance
operation, a restore redundancy operation will attempt to bring each included region to its
configured redundancy level by creating redundant copies of buckets, and will also optionally
reassign which members host the primary buckets for better load balancing. A restore redundancy
operation differs from a rebalance operation in that it will not move buckets from one member
to another.Set<CompletableFuture<RestoreRedundancyResults>> getRestoreRedundancyFutures()
void setCriticalHeapPercentage(float heapPercentage)
Changing this value can cause LowMemoryException
to be thrown from the following
Cache
operations:
Region.put(Object, Object)
Region.put(Object, Object, Object)
Region.create(Object, Object)
Region.create(Object, Object, Object)
Region.putAll(java.util.Map)
Function
s whose Function.optimizeForWrite()
returns true.
Only one change to this attribute or the eviction heap percentage will be allowed at any given
time and its effect will be fully realized before the next change is allowed.
When using this threshold, the VM must be launched with the -Xmx
and
-Xms
switches set to the same values. Many virtual machine implementations have
additional VM switches to control the behavior of the garbage collector. We suggest that you
investigate tuning the garbage collector when using this type of eviction controller. A
collector that frequently collects is needed to keep our heap usage up to date. In particular,
on the Sun HotSpot VM,
before Java 14,
the -XX:+UseConcMarkSweepGC
flag needs to be set, and
-XX:CMSInitiatingOccupancyFraction=N
should be set with N being a percentage that
is less than the ResourceManager
critical and eviction heap thresholds.
The JRockit VM has similar flags, -Xgc:gencon
and -XXgcTrigger:N
,
which are required if using this feature. Please Note: the JRockit gcTrigger flag is based on
heap free, not heap in use like the GemFire parameter. This means you need to set gcTrigger to
100-N. for example, if your eviction threshold is 30 percent, you will need to set gcTrigger to
70 percent.
On the IBM VM, the flag to get a similar collector is -Xgcpolicy:gencon
, but there
is no corollary to the gcTrigger/CMSInitiatingOccupancyFraction flags, so when using this
feature with an IBM VM, the heap usage statistics might lag the true memory usage of the VM,
and thresholds may need to be set sufficiently high that the VM will initiate GC before the
thresholds are crossed.
heapPercentage
- a percentage of the maximum tenured heap for the VMIllegalStateException
- if the heapPercentage value is not >= 0 or <= 100 or when
less
than the current eviction heap percentagegetCriticalHeapPercentage()
,
getEvictionHeapPercentage()
float getCriticalHeapPercentage()
setCriticalHeapPercentage(float)
void setCriticalOffHeapPercentage(float offHeapPercentage)
Changing this value can cause LowMemoryException
to be thrown from the following
Cache
operations:
Region.put(Object, Object)
Region.put(Object, Object, Object)
Region.create(Object, Object)
Region.create(Object, Object, Object)
Region.putAll(java.util.Map)
Function
s whose Function.optimizeForWrite()
returns true.
Only one change to this attribute or the eviction off-heap percentage will be allowed at any given time and its effect will be fully realized before the next change is allowed.
offHeapPercentage
- a percentage of the maximum off-heap memory availableIllegalStateException
- if the ofHeapPercentage value is not >= 0 or <= 100 or when
less
than the current eviction off-heap percentagegetCriticalOffHeapPercentage()
,
getEvictionOffHeapPercentage()
float getCriticalOffHeapPercentage()
setCriticalOffHeapPercentage(float)
void setEvictionHeapPercentage(float heapPercentage)
Changing this value may cause eviction to begin immediately.
Only one change to this attribute or critical heap percentage will be allowed at any given time and its effect will be fully realized before the next change is allowed. This feature requires additional VM flags to perform properly. See setCriticalHeapPercentage() for details.
heapPercentage
- a percentage of the maximum tenured heap for the VMIllegalStateException
- if the heapPercentage value is not >= 0 or <= 100 or when
greater
than the current critical heap percentage.getEvictionHeapPercentage()
,
getCriticalHeapPercentage()
float getEvictionHeapPercentage()
setEvictionHeapPercentage(float)
void setEvictionOffHeapPercentage(float offHeapPercentage)
Changing this value may cause eviction to begin immediately.
Only one change to this attribute or critical off-heap percentage will be allowed at any given time and its effect will be fully realized before the next change is allowed.
offHeapPercentage
- a percentage of the maximum off-heap memory availableIllegalStateException
- if the offHeapPercentage value is not >= 0 or <= 100 or
when
greater than the current critical off-heap percentage.getEvictionOffHeapPercentage()
,
getCriticalOffHeapPercentage()
float getEvictionOffHeapPercentage()
setEvictionOffHeapPercentage(float)