The shutdown process is initiated.
Server shutdown can be initiated several ways. For
example, a user with the
privilege can execute a mysqladmin
shutdown command. mysqladmin
can be used on any platform supported by MySQL. Other
operating system-specific shutdown initiation methods are
possible as well: The server shuts down on Unix when it
SIGTERM signal. A server
running as a service on Windows shuts down when the
services manager tells it to.
The server creates a shutdown thread if necessary.
Depending on how shutdown was initiated, the server might
create a thread to handle the shutdown process. If
shutdown was requested by a client, a shutdown thread is
created. If shutdown is the result of receiving a
SIGTERM signal, the signal thread might
handle shutdown itself, or it might create a separate
thread to do so. If the server tries to create a shutdown
thread and cannot (for example, if memory is exhausted),
it issues a diagnostic message that appears in the error
Error: Can't create thread to kill server
The server stops accepting new connections.
To prevent new activity from being initiated during
shutdown, the server stops accepting new client
connections. It does this by closing the network
connections to which it normally listens for connections:
the TCP/IP port, the Unix socket file, the Windows named
pipe, and shared memory on Windows.
The server terminates current activity.
For each thread that is associated with a client
connection, the connection to the client is broken and the
thread is marked as killed. Threads die when they notice
that they are so marked. Threads for idle connections die
quickly. Threads that currently are processing statements
check their state periodically and take longer to die. For
additional information about thread termination, see
Section 188.8.131.52, “
KILL Syntax”, in particular for the instructions
REPAIR TABLE or
OPTIMIZE TABLE operations on
For threads that have an open transaction, the transaction
is rolled back. Note that if a thread is updating a
non-transactional table, an operation such as a
INSERT may leave the table partially
updated, because the operation can terminate before
If the server is a master replication server, threads
associated with currently connected slaves are treated
like other client threads. That is, each one is marked as
killed and exits when it next checks its state.
If the server is a slave replication server, the I/O and
SQL threads, if active, are stopped before client threads
are marked as killed. The SQL thread is allowed to finish
its current statement (to avoid causing replication
problems), and then stops. If the SQL thread was in the
middle of a transaction at this point, the transaction is
Storage engines are shut down or closed.
At this stage, the table cache is flushed and all open
tables are closed.
Each storage engine performs any actions necessary for
tables that it manages. For example,
MyISAM flushes any pending index writes
for a table.
InnoDB flushes its buffer
pool to disk, unless
innodb_fast_shutdown is 2, writes the
current LSN to the tablespace, and terminates its own
The server exits.