#include <db_cxx.h> int DbEnv::set_cache_max(u_int32_t gbytes, u_int32_t bytes);
Sets the maximum cache size in bytes. The specified size is rounded to the nearest multiple of the cache region size, which is the initial cache size divided by the number of regions specified to the DbEnv::set_cachesize() method. If no value is specified, it defaults to the initial cache size.
The database environment's maximum cache size may also be configured using the environment's DB_CONFIG file. The syntax of the entry in that file is a single line with the string "set_cache_max", one or more whitespace characters, and the maximum cache size in bytes, specified in two parts: the gigabytes of cache and the additional bytes of cache. Because the DB_CONFIG file is read when the database environment is opened, it will silently overrule configuration done before that time.
The DbEnv::set_cache_max()
method configures a database environment,
not only operations performed using the specified
DbEnv handle.
The DbEnv::set_cache_max()
method may be called at any time during
the life of the application.
The DbEnv::set_cache_max()
method either returns a non-zero error value or throws an
exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
The gbytes parameter specifies the number of bytes which, when added to the bytes parameter, specifies the maximum size of the cache.
The DbEnv::set_cache_max()
method may fail and throw a DbException
exception, encapsulating one of the following non-zero errors, or return one
of the following non-zero errors: