MySQL 5.6 Reference Manual Including MySQL NDB Cluster 7.3-7.4 Reference Guide
These thread states are associated with processing for
DELAYED
inserts (see
Section 13.2.5.3, “INSERT DELAYED Statement”). Some states are associated
with connection threads that process INSERT
DELAYED
statements from clients. Other states are
associated with delayed-insert handler threads that insert the
rows. There is a delayed-insert handler thread for each table
for which INSERT DELAYED
statements are issued.
States associated with a connection thread that processes an
INSERT DELAYED
statement from the
client:
The thread is preparing to feed rows to the delayed-insert handler thread.
The thread is creating a handler for
DELAYED
inserts.
This occurs before the allocating local
table
state and after the waiting for
handler lock
state, when the connection thread
gets access to the delayed-insert handler thread.
This occurs after the waiting for handler
open
state. The delayed-insert handler thread has
signaled that it has ended its initialization phase, which
includes opening the table for delayed inserts.
The thread is adding a new row to the list of rows that the delayed-insert handler thread must insert.
This occurs during the initialization phase when the thread is trying to find the delayed-insert handler thread for the table, and before attempting to gain access to the list of delayed-insert threads.
An INSERT DELAYED
handler has
processed all pending inserts and is waiting for new ones.
This occurs before the allocating local
table
state when the connection thread waits for
access to the delayed-insert handler thread.
This occurs after the Creating delayed
handler
state and before the got old
table
state. The delayed-insert handler thread has
just been started, and the connection thread is waiting for
it to initialize.
States associated with a delayed-insert handler thread that inserts the rows:
The state that occurs just before inserting rows into the table.
After inserting a number of rows, the delayed-insert thread sleeps to let other threads do work.
A delayed-insert handler is trying to get a lock for the table to insert rows.
A delayed-insert handler is waiting for a connection thread
to add rows to the queue (see storing row into
queue
).