The is an entry cache implementation which uses
a JE database to keep track of the entries.
For the best performance the JE database should reside in a memory based
file system, although any file system will do for this cache to function.
Entries are maintained either by FIFO (default) or LRU (configurable)
based list implementation.
Cache sizing is based on the size or percentage of free space availble in
the file system, such that if enough memory is free, then adding an entry
to the cache will not require purging, but if more than a specified
percentage of the file system available space is already consumed, then
one or more entries will need to be removed in order to make room for a
new entry. It is also possible to configure a maximum number of entries
for the cache. If this is specified, then the number of entries will not
be allowed to exceed this value, but it may not be possible to hold this
many entries if the available memory fills up first.
Other configurable parameters for this cache include the maximum length of
time to block while waiting to acquire a lock, and a set of filters that
may be used to define criteria for determining which entries are stored in
the cache. If a set of filters are provided then an entry must match at
least one of them in order to be stored in the cache.
JE environment cache size can also be configured either as percentage of
the free memory available in the JVM, or as an absolute size in bytes.
This cache has a persistence property which, if enabled, allows for the
contents of the cache to persist across server or cache restarts.
1.3.6.1.4.1.26027.1.2.110
ds-cfg-file-system-entry-cache
ds-cfg-entry-cache
The length of time in milliseconds to wait while
attempting to acquire a read or write lock.
2000.0ms
1.3.6.1.4.1.26027.1.1.58
ds-cfg-lock-timeout
The maximum size of the entry cache in bytes.
0b
1.3.6.1.4.1.26027.1.1.362
ds-cfg-max-memory-size
The maximum number of entries allowed in the cache.
2147483647
1.3.6.1.4.1.26027.1.1.65
ds-cfg-max-entries
Specifies the policy which should be used for purging entries from the
cache. FIFO by default and LRU as configurable.
fifo
FIFO based entry cache.
LRU based entry cache.
1.3.6.1.4.1.26027.1.1.363
ds-cfg-cache-type
Specifies the directory in which the JE environment should store the
cache.
/tmp/OpenDS.FSCache
1.3.6.1.4.1.26027.1.1.364
ds-cfg-cache-directory
Specifies whether the cache should persist across restarts.
false
1.3.6.1.4.1.26027.1.1.365
ds-cfg-persistent-cache
The maximum memory usage for the internal JE cache as a percentage
of the total JVM memory.
0
1.3.6.1.4.1.26027.1.1.25
ds-cfg-database-cache-percent
The maximum JVM memory usage in bytes for the internal JE cache.
0b
1.3.6.1.4.1.26027.1.1.27
ds-cfg-database-cache-size
org.opends.server.extensions.FileSystemEntryCache