rvm_truncate

NAME

rvm_truncate - truncate the log by applying committed changes to data segments

SYNOPSIS

#include "rvm.h"

rvm_return_t rvm_truncate ()

DESCRIPTION

rvm_truncate applies all committed transaction records in the log to their corresponding data segments and reclaims the log space used by those records.

This operation is necessary for continued operation of RVM. As transactions commit, the log fills up. Periodically, the log must be truncated to free space for new transaction records.

RVM can be configured to automatically truncate the log when it reaches a certain threshold percentage full (specified in the options during initialization). Alternatively, applications can call rvm_truncate explicitly to control when truncation occurs.

Truncation involves reading all unapplied transaction records from the log, applying them to the appropriate segments, and then reclaiming the log space. This is a potentially expensive operation, but it ensures that the log does not grow unboundedly.

DIAGNOSTICS

RVM_SUCCESS: success
RVM_ELOG: log file not open or error during truncation
RVM_EIO: I/O error during truncation
RVM_ENO_MEMORY: heap exhausted during truncation
RVM_EPORTABILITY: internal portability problem, see system maintainer

AUTHOR

Hank Mashburn