/*
* @- TMcommit
* global commit without any multi-threaded access assumptions, thus
* taking all BBP locks. It creates a new database checkpoint.
*/
gdk_return
TMcommit(void)
{
gdk_return ret = GDK_FAIL;
/* commit with the BBP globally locked */
BBPlock();
if (prelude(getBBPsize(), NULL) == GDK_SUCCEED &&
BBPsync(getBBPsize(), NULL) == GDK_SUCCEED) {
epilogue(getBBPsize(), NULL);
ret = GDK_SUCCEED;
}
BBPunlock();
return ret;
}
/*
* @- TMsubcommit
*
* Create a new checkpoint that is equal to the previous, with the
* exception that for the passed list of batnames, the current state
* will be reflected in the new checkpoint.
*
* On the bats in this list we assume exclusive access during the
* operation.
*
* This operation is useful for e.g. adding a new XQuery document or
* SQL table to the committed state (after bulk-load). Or for dropping
* a table or doc, without forcing the total database to be clean,
* which may require a lot of I/O.
*
* We expect the globally locked phase (BBPsync) to take little time
* (<100ms) as only the BBP.dir is written out; and for the existing
* bats that were modified, only some heap moves are done (moved from
* BAKDIR to SUBDIR). The atomic commit for sub-commit is the rename
* of SUBDIR to DELDIR.
*
* As it does not take the BBP-locks (thanks to the assumption that
* access is exclusive), the concurrency impact of subcommit is also
* much lighter to ongoing concurrent query and update facilities than
* a real global TMcommit.
*/
gdk_return
TMsubcommit_list(bat *subcommit, int cnt)
{
int xx;
gdk_return ret = GDK_FAIL;
assert(cnt > 0);
assert(subcommit[0] == 0); /* BBP artifact: slot 0 in the array will be ignored */
/* sort the list on BAT id */
GDKqsort(subcommit + 1, NULL, NULL, cnt - 1, sizeof(bat), 0, TYPE_bat);
assert(cnt == 1 || subcommit[1] > 0); /* all values > 0 */
/* de-duplication of BAT ids in subcommit list
* this is needed because of legacy reasons (database
* upgrade) */
for (xx = 2; xx < cnt; xx++) {
if (subcommit[xx-1] == subcommit[xx]) {
int i;
cnt--;
for (i = xx; i < cnt; i++)
subcommit[i] = subcommit[i+1];
}
}
if (prelude(cnt, subcommit) == GDK_SUCCEED) { /* save the new bats outside the lock */
/* lock just prevents BBPtrims, and other global
* (sub-)commits */
for (xx = 0; xx <= BBP_THREADMASK; xx++)
MT_lock_set(&GDKtrimLock(xx));
if (BBPsync(cnt, subcommit) == GDK_SUCCEED) { /* write BBP.dir (++) */
epilogue(cnt, subcommit);
ret = GDK_SUCCEED;
}
for (xx = BBP_THREADMASK; xx >= 0; xx--)
MT_lock_unset(&GDKtrimLock(xx));
}
return ret;
}
str
TRNglobal_sync(bit *ret)
{
*ret = BBPsync(getBBPsize(),NULL)?FALSE:TRUE;
return MAL_SUCCEED;
}
str
TRNglobal_sync(bit *ret)
{
*ret = BBPsync(getBBPsize(), NULL) == GDK_SUCCEED;
return MAL_SUCCEED;
}
