Oracle 5.0, Справочное руководство

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Server System Variables
499
Option Sets Variable Yes,
table_lock_wait_timeout
[498]
Variable Name
table_lock_wait_timeout
Variable Scope Global
Dynamic Variable Yes
Permitted Values
Type
numeric
Default
50
Range
1 .. 1073741824
This variable is unused.
•
table_type
[499]
Variable Name
table_type
Variable Scope Global, Session
Dynamic Variable Yes
Deprecated 5.2.5, by
storage_engine
Permitted Values
Type
enumeration
This variable is a synonym for
storage_engine
[497] . In MySQL 5.0,
storage_engine
[497]
is the preferred name;
table_type
[499] is deprecated and is removed in MySQL 5.5.
•
thread_cache_size
[499]
Command-Line Format
--thread_cache_size=#
Option-File Format
thread_cache_size
Option Sets Variable Yes,
thread_cache_size
[499]
Variable Name
thread_cache_size
Variable Scope Global
Dynamic Variable Yes
How many threads the server should cache for reuse. When a client disconnects, the client's threads
are put in the cache if there are fewer than
thread_cache_size
[499] threads there. Requests
for threads are satisfied by reusing threads taken from the cache if possible, and only when the
cache is empty is a new thread created. This variable can be increased to improve performance
if you have a lot of new connections. Normally, this does not provide a notable performance
improvement if you have a good thread implementation. However, if your server sees hundreds
of connections per second you should normally set
thread_cache_size
[499] high enough
so that most new connections use cached threads. By examining the difference between the
Connections
[524] and
Threads_created
[534] status variables, you can see how efficient
the thread cache is. For details, see Section 5.1.6, “Server Status Variables” .
•
thread_concurrency
[499]
Command-Line Format
--thread_concurrency=#
Option-File Format
thread_concurrency
Option Sets Variable Yes,
thread_concurrency
[499]
Variable Name
thread_concurrency
Variable Scope Global