This patch removes log_position from streaming_context. The
log_position was meant for keeping track of the database specific
position corresponding to the changes that have been already
replicated by a streaming transaction. In reality, things may be more
complex in the DBMS side and a size_t may be unsufficient to keep
track of the progress of a streaming transaction. For example, in
MariaDB, it may be necessary to keep track of positions in both
transaction and statement caches. Suggesting that the responsibility
of tracking these position(s) should be delegated to client_service.
The log_position was also used to do sanity checks in
streaming_step(). Those sanity checks are preserved by simply keeping
track of the number of bytes that were certified by the streaming
transaction.
Remove bf abort handling `client_state::after_statement()`, since the
same logic already appears later in `transaction::after_statement()`.
Also, introduce `transaction::after_statement()` overload which takes
a lock.
The transaction state is set to s_ordered_commit in
ordered_commit(). However, this is too late for making the
transaction immune for BF aborts after commit order has
been established, which happens in before_commit().
Moving the state change into before_commit() would be the
right thing to do, but that would require too many fixes
to existing applications which are using the lib.
In order to make the transaction immune for BF abort
after it has been ordered to commit, introduce additional
boolean flag which is set to true at the end of before_commit()
and is taken into account in bf_abort().
Make is_rollbacker_active() public so that the BF thread can
check if the rollbacker was started or not.
Also don't unlock the lock for launching the background
rollbacker to avoid race conditions in accessing the
victim state.
Added methods bf_abort() and total_order_bf_abort() which take
wsrep::unique_lock<wsrep::mutex> as argument to allow caller
to grab the mutex before attempting BF abort. The old calls
were kept for backwards compatibility and wrap the new calls
with internal locking.
The condition to skip changing to `s_joined` for all codepaths
which return from donor state. Extracted the logic into separate
method.
Commented start_sst_action in mock_server_service.
Use pointers to pass state objects to service constructors
to work around GCC 12 warning
error: member ‘wsrep::mock_storage_service::client_state_’
is used uninitialized
Removed calls to assert() from public headers to have
full control when assertions are enabled in wsrep-lib
code regardless of parent project build configuration.
Moved methods containing assertions and non-trivial
code from headers into compilation units.
Changed server_state public methods sst_received() and wait_until_state()
to report errors as return value instead of throwing exceptions.
This was done to gradually get rid of public methods which report
errors via exceptions.
This change was part of MDEV-30419.
Report event will write json formatted event into report
file.
Include Boost headers as system headers to avoid generating
excessive warnings. Enable extra tests for selected compilers
in actions.
- Change default WITH_BOOST path to reside inside source tree
to avoid permission problems or accidentally overwriting
directories outside source tree.
- If system Boost installation is not found, optionally use
header only unit test framework from location specified by
WITH_BOOST.
- Fix extra-semi warning in provider_options.hpp.
This commit introduces provider_options module which
acts as a proxy between application and wsrep provider
library.
When initialized, the provider options are read from the
provider through config service api extension. A lookup
table with current values and defaults is constructed.
Parameter names are mapped so that dots in provider parameter
names are transformed to underscores.
The fallthrough comment is not enough to silence the warning
with -Wimplicit-fallthrough=5.
This commit also fixes submodule handling in github actions.
This patch introduces a queue to store ids of transactions that failed
to send a rollback fragment in streaming_rollback(). This is to avoid
potentially missed rollback fragments when a cluster splits and then
later reforms. Rollback fragments would be missing if a node rolled
back a transaction locally (either BFed or voluntary rollback) while
non-primary, and the attempt to send rollback fragment failed in
transaction::streaming_rollback().
Transaction that fail to send rollback fragment can proceed to
rollback locally. However we must ensure that rollback fragments for
those transactions are eventually delivered by the cluster. This must
be done before a potentially conflicting writeset causes BF-BF
conflicts in the rest of the cluster.
Handle the case were prepare is bf aborted after it has replicated a
fragment, and before the command finishes in
after_command_before_result() and after_command_after_result() hooks.
Assertion is_streaming() fires in transaction::adopt() when a
transaction is BF aborted, while it is in s_executing state, and it
manages to complete rollback and cleanup while the BF aborter is
executing streaming_rollback() with client_state lock is unlocked.
In this case method transaction::adopt() finds a transaction that is
no longer marked as streaming, triggering the assertion.
A condition variable and flag streaming_rollback_in_progress_ now
prevents a client thread to finish rollback, even if the BF aborter
has temporarily unlocked the client_state lock.
Remove the method as it does nothing, except for calling
`streaming_context_.clear()`. This led to a situation where we have
two ways to do the same thing, and it is annoying, if one wants to search
for all places where streaming_context is cleaned up.
* Removed transaction::p_unsafe_ member
* Changed transaction::pa_unsafe(bool) to modify flags member directly
* Modified transaction.cpp to use transaction.pa_unsafe(bool) rather than
directly changing transaction's flag
* added method mark_transaction_pa_unsafe() for client_state,
application will use this
This commit defines a TLS service interface. If the implementation is
provided by the application when the provider is loaded, appropriate
hooks are probed from the provider and the provider side hooks are
initialized after the provider is loaded.
A sample implementation to demostrate the use of TLS interface
is provided in dbsim/db_tls.cpp.
Also contains a change to thread service interface: The
thread exit virtual method was changed to function pointer
to allow thread exit path which does not involve C++.
The method takes already locked lock object as an argument.
The caller must ensure that the lock object owns the underlying mutex.
Replaced homegrown wsrep::unique_lock with type alias from
std::unique_lock.
This patch adds the possibility to have client commands that do not
return results from DBMS. While processing such commands we must be
able to preserve errors until the next interaction with client.
Specifically if the transaction is bf aborted while processing such
a non-returning command, then we have to keep the deadlock error until
the client issues a command that may return the error.
To handle such cases, client_state::before_command() now takes
parameter keep_command_error. The DBMS is supposed set
keep_command_error true to instruct wsrep-lib to preserve errors (if
any) until the next command which sets keep_command_error false.
Dealing with a case where current client command does not return result.
Work in progress.
Fix typo and add assertions in keep_command_error()
Make keep_command_error a parameter to before_commit()
Fix comment about keep_command_error
Handle keep_command_error with s_must_abort in wsrep_before_command()
Fix unit test
* Added unit tests for transaction::xa_detach() and
transaction::xa_replay()
* Added unit tests for wsrep::xid
* Fixed minor issues pointed out by reviewer
This patch implments replaying for prepared XA transactions.
Replay may happen in the following cases:
1) The transaction is BF aborted in prepared state and is idle. In
that case, the transaction is handed over to rollbacker for replay.
2) The transaction is BF aborted while executing the
commit (i.e. before or after successful certification). In
which case the transaction replays itself from fragment storage.
3) The transaction is BF aborted while certifying its commit
fragment. This case is handled like replay for streaming transactions,
where the provider is directly involved and re-delivers the last
fragment.
Add support for detaching XA transactions. This is useful for handling
the case where the DBMS client has a transaction in prepared state and
disconnects. Before disconnect, the DBMS calls the newly introduced
client_state::xa_detach(), to cleanup the local transaction and
convert it to a high priority transaction. The DBMS may later attempt
to terminate the transaction through client_state::commit_by_xid() or
client_state::rollback_by_xid().
Also in this patch:
- Fix client_state::close() so that it does not rollback transactions
in prepared state
- Changed class wsrep::xid representation to hold enough information
so that DBMS can convert to its native representation
- Fix potential infinite loop in
server_state::find_streaming_applier(wsrep:xid&)
- Append SR keys on prepare fragment and make it pa_unsafe
- Handle one phase commit (simply fall back to two phase)
- Do not rollback prepared streaming clients in
server_state::close_orphaned_transactions()
which complicates diagnostics and debugging.
Don't ignore provider return codes and more verbose error logging for
sst_sent(), sst_received(), set_encryption_key() methods
Refs codership/wsrep-lib#127
After a local certification failure, commit order is released without
the setting the current position in DBMS. Which results in diverging
positions between provider and DBMS, if clean shutdown happens right
after local certification failure.
This patch add method set_position() to server_service class. So that
wsrep-lib can instruct DBMS to set the current position after local
certification failure releases commit order.
If the transaction fails during replay because of certification
failure, the provider will return control to applier without
terminating the transaction and transaction remains in
s_replaying.
Fixed transaction::after_statement() to handle the state changes
correctly if certification failure is returned from replay.
Replaying was extracted to separate private method from
after_statement(). Removed transaction::after_replay() as it
seems now unnecessary and it bypassed state change sanity checks.
Allowed replaying -> committed transaction transition to handle
the situation where DBMS allocates a new context and client_state
to do the replay.
