Oracle 5.0 Reference Manual page 1632

MySQL Server Options and Variables for MySQL Cluster
Variable Scope
Dynamic Variable
The maximum number of ranges to send to a table handler at once during range selects. The default
value is 256. Sending multiple ranges to a handler at once can improve the performance of certain
selects dramatically. This is especially true for the
the range requests to all nodes. Sending a batch of those requests at once reduces communication
costs significantly.
This variable was added in MySQL 5.0.3.
•
ndb_autoincrement_prefetch_sz
Command-Line Format
Option-File Format
Option Sets Variable
Variable Name
Variable Scope
Dynamic Variable
Determines the probability of gaps in an autoincremented column. Set it to
Setting it to a high value for optimization—makes inserts faster, but decreases the likelihood that
consecutive autoincrement numbers will be used in a batch of inserts. Default value: 32. Minimum
value: 1.
Beginning with MySQL 5.0.56, this variable affects the number of
fetched between statements only. Within a statement, at least 32 IDs are now obtained at a time.
The default value for
of statements inserting single rows. (Bug #31956)
Important
This variable does not affect inserts performed using
•
ndb_cache_check_time
Command-Line Format
Option-File Format
Global, Session
Yes
Permitted Values
Type
numeric
Default
256
Range
1 .. 4294967295
[1612]
--ndb_autoincrement_prefetch_sz
ndb_autoincrement_prefetch_sz
Yes,
ndb_autoincrement_prefetch_sz
ndb_autoincrement_prefetch_sz
Global, Session
Yes
Permitted Values (<= 5.0.55)
Type
numeric
Default
32
Range
1 .. 256
Permitted Values (>= 5.0.56)
Type
numeric
Default
1
Range
1 .. 256
ndb_autoincrement_prefetch_sz
[1612]
--ndb_cache_check_time
ndb_cache_check_time
1612
table handler, which needs to send
NDBCLUSTER
AUTO_INCREMENT
[1612] is now 1, to increase the speed
INSERT ...
[1612]
to minimize this.
1
IDs that are
SELECT.