.I,Berkeley DB: DbMpool::trickle[P

DbMpool::trickle





#include <db_cxx.h>

int(DbMpool::trickle(int pct, int *nwrotep);





Description



GThe DbMpool::trickle method ensures that at least pct percent ofGthe pages in the shared memory pool are clean by writing dirty pages totheir backing files.DIf the nwrotep argument is non-NULL, the number of pages thatFwere written to reach the correct percentage is returned in the memorylocation it references.?

The purpose of the DbMpool::trickle function is to enable aImemory pool manager to ensure that a page is always available for reading6in new information without having to wait for a write.

The DbMpool::trickle>method either returns errno or throws an exception that:encapsulates an errno on failure, and 0 on success.



Errors

WIf a fatal error occurs in Berkeley DB, the DbMpool::trickle method may fail and eitherIreturn DB_RUNRECOVERY or throw an exception encapsulating DB_RUNRECOVERY,Gat which point all subsequent database calls will also fail in the sameFway. Methods marked as returning errno will, by default, throwHan exception that encapsulates the error information. The default error\behavior can be changed, see DbException.

The DbMpool::trickle&method may fail and throw an exceptionKfor any of the errors specified for the following Berkeley DB and C library functions:DBmemp->pgin(3),DBmemp->pgout(3), abort(3), close(3),dbenv->db_paniccall(3), fcntl(3), fflush(3), fprintf(3),free(3), fstat(3), fsync(3), getenv(3), getpid(3), getuid(3), isdigit(3),>DbLog::compare,:DbLog::flush, lseek(3), malloc(3), memcmp(3), memcpy(3), memset(3),mmap(3),open(3), pread(3),pstat_getdynamic(3), pwrite(3),read(3),sigfillset(3),sigprocmask(3),stat(3), strerror(3), strlen(3), sysconf(3),time(3), unlink(3), vfprintf(3), vsnprintf(3),and write(3).

!In addition, the DbMpool::trickle&method may fail and throw an exceptionor return errnofor the following conditions:

B

EINVAL
An invalid flag value or parameter was specified.







Class

6DbMpool



See Also

>DbMpool::close,<DbMpool::open,JDbMpool::db_register,<DbMpool::stat,<DbMpool::sync,DbMpool::trickleand@DbMpool::unlink.
ÿÿ