// on input, _initLock is held, so this can be called by only one thread at a time,
// also, on input, the CollectionMap must be allocated
Collection *CollectionMap::open_ns(const StringData& ns, const bool bulkLoad) {
verify(allocated());
BSONObj serialized;
BSONObj nsobj = BSON("ns" << ns);
storage::Key sKey(nsobj, NULL);
DBT ndbt = sKey.dbt();
// If this transaction is read only, then we cannot possible already
// hold a lock in the metadb and we certainly don't need to hold one
// for the duration of this operation. So we use an alternate txn stack.
const bool needAltTxn = !cc().hasTxn() || cc().txn().readOnly();
scoped_ptr<Client::AlternateTransactionStack> altStack(!needAltTxn ? NULL :
new Client::AlternateTransactionStack());
scoped_ptr<Client::Transaction> altTxn(!needAltTxn ? NULL :
new Client::Transaction(0));
// Pass flags that get us a write lock on the metadb row
// for the ns we'd like to open.
DB *db = _metadb->db();
const int r = db->getf_set(db, cc().txn().db_txn(), DB_SERIALIZABLE | DB_RMW,
&ndbt, getf_serialized, &serialized);
if (r == 0) {
// We found an entry for this ns and we have the row lock.
// First check if someone got the lock before us and already
// did the open.
Collection *cl = find_ns(ns);
if (cl != NULL) {
return cl;
}
// No need to hold the openRWLock during Collection::make(),
// the fact that we have the row lock ensures only one thread will
// be here for a particular ns at a time.
shared_ptr<Collection> details = Collection::make( serialized, bulkLoad );
SimpleRWLock::Exclusive lk(_openRWLock);
verify(!_collections[ns]);
_collections[ns] = details;
return details.get();
} else if (r != DB_NOTFOUND) {
storage::handle_ydb_error(r);
}
return NULL;
}
void Dictionary::open(const BSONObj &info,
const mongo::Descriptor &descriptor, const bool may_create,
const bool hot_index) {
int readPageSize = 65536;
int pageSize = 4 * 1024 * 1024;
TOKU_COMPRESSION_METHOD compression = TOKU_ZLIB_WITHOUT_CHECKSUM_METHOD;
BSONObj key_pattern = info["key"].Obj();
BSONElement e;
e = info["readPageSize"];
if (e.ok() && !e.isNull()) {
readPageSize = BytesQuantity<int>(e);
uassert(16743, "readPageSize must be a number > 0.", readPageSize > 0);
TOKULOG(1) << "db " << _dname << ", using read page size " << readPageSize << endl;
}
e = info["pageSize"];
if (e.ok() && !e.isNull()) {
pageSize = BytesQuantity<int>(e);
uassert(16445, "pageSize must be a number > 0.", pageSize > 0);
TOKULOG(1) << "db " << _dname << ", using page size " << pageSize << endl;
}
e = info["compression"];
if (e.ok() && !e.isNull()) {
std::string str = e.String();
if (str == "lzma") {
compression = TOKU_LZMA_METHOD;
} else if (str == "quicklz") {
compression = TOKU_QUICKLZ_METHOD;
} else if (str == "zlib") {
compression = TOKU_ZLIB_WITHOUT_CHECKSUM_METHOD;
} else if (str == "none") {
compression = TOKU_NO_COMPRESSION;
} else {
uassert(16442, "compression must be one of: lzma, quicklz, zlib, none.", false);
}
TOKULOG(1) << "db " << _dname << ", using compression method \"" << str << "\"" << endl;
}
int r = _db->set_readpagesize(_db, readPageSize);
if (r != 0) {
handle_ydb_error(r);
}
r = _db->set_pagesize(_db, pageSize);
if (r != 0) {
handle_ydb_error(r);
}
r = _db->set_compression_method(_db, compression);
if (r != 0) {
handle_ydb_error(r);
}
// If this is a non-creating open for a read-only (or non-existent)
// transaction, we can use an alternate stack since there's nothing
// to roll back and no locktree locks to hold.
const bool needAltTxn = !may_create && (!cc().hasTxn() || cc().txn().readOnly());
scoped_ptr<Client::AlternateTransactionStack> altStack(!needAltTxn ? NULL :
new Client::AlternateTransactionStack());
scoped_ptr<Client::Transaction> altTxn(!needAltTxn ? NULL :
new Client::Transaction(0));
const int db_flags = may_create ? DB_CREATE : 0;
r = _db->open(_db, cc().txn().db_txn(), _dname.c_str(), NULL,
DB_BTREE, db_flags, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);
if (r == ENOENT && !may_create) {
throw NeedsCreate();
}
if (r != 0) {
handle_ydb_error(r);
}
if (may_create) {
set_db_descriptor(_db, descriptor, hot_index);
}
verify_or_upgrade_db_descriptor(_db, descriptor, hot_index);
if (altTxn.get() != NULL) {
altTxn->commit();
}
}
