Table of Contents
Where Ehcache stores data?
Data stores supported by Ehcache include:
- On-Heap Store – Utilizes Java’s on-heap RAM memory to store cache entries.
- Off-Heap Store – Limited in size only by available RAM.
- Disk Store – Utilizes a disk (file system) to store cache entries.
- Clustered Store – This data store is a cache on a remote server.
How do you use Ehcache?
General-Purpose Caching
- Use Java 1.5 or 1.6.
- Place the Ehcache jar into your classpath.
- Configure ehcache. xml and place it in your classpath.
- Optionally, configure an appropriate logging level. See the Code Samples chapter for more information on direct interaction with ehcache.
What is timeToLiveSeconds in Ehcache?
timeToLiveSeconds – The maximum number of seconds an element can exist in the cache regardless of use. The element expires at this limit and will no longer be returned from the cache. The default value is 0, which means no TTL eviction takes place (infinite lifetime).
Why is cache faster than RAM?
Cache memory allows for faster access to data for two reasons: cache uses Static RAM whereas Main Memory (RAM) uses dynamic RAM. cache memory stores instructions the processor may require next, which can then be retrieved faster than if they were held in RAM.
What is Memorystoreevictionpolicy in Ehcache?
The policy used to evict elements from the MemoryStore . This can be one of: LRU – least recently used. LFU – least frequently used. FIFO – first in first out, the oldest element by creation time.
What is Ehcache timeToIdleSeconds?
timeToIdleSeconds – The maximum number of seconds an element can exist in the cache without being accessed. The element expires at this limit and will no longer be returned from the cache. The default value is 0, which means no TTI eviction takes place (infinite lifetime).
What is maxbyteslocalheap?
The maximum number of cache entries or bytes a cache can use in local heap memory, or, when set at the CacheManager level (maxBytesLocalHeap only), a local pool available to all caches under that CacheManager. This setting is required for every cache or at the CacheManager level.
Why can’t I add off-heap caches to my cachemanager?
If a CacheManager has a pool configured for off-heap, your application cannot add caches dynamically that have off-heap configuration — doing so generates an error. In addition, if any caches that used the pool are removed programmatically or through the Developer Console, other caches in the pool cannot claim the unused portion.
What is BigMemory go in caching?
This setting is required for every cache or at the CacheManager level. This tier is available with BigMemory Go .The maximum number of bytes a cache can use in off-heap memory, or, when set at the CacheManager level, as a pool available to all caches under that CacheManager. This setting requires BigMemory.
How much memory does a cachemanager pool share?
For example, if CacheManager with eight caches pools one gigabyte of heap, and two caches each explicitly specify 200MB of heap while the remaining caches do not specify a size, the remaining caches will share 600MB of heap equally.