|
Re: Latches in Oracle [message #56724 is a reply to message #56671] |
Sun, 20 April 2003 04:26 ![Go to previous message Go to previous message](/forum/theme/orafaq/images/up.png) |
Frank Naude
Messages: 4593 Registered: April 1998
|
Senior Member |
|
|
Hi,
A latch is an internal Oracle mechanism used to protect data structures in the SGA from simultaneous access. Atomic hardware instructions like TEST-AND-SET are used to implement latches. Latches are more restrictive than locks in that they are always exclusive. Latches are never queued, but will spin or sleep until they obtain a resource, or time out.
For more details, see the Internals FAQ at http://www.orafaq.net/faqdbain.htm
Best regards.
Frank
|
|
|