MongoCursor::immortal
(PECL mongo >=1.0.1)
MongoCursor::immortal — Sets whether this cursor will timeout
说明
$liveForever = true
] )After remaining idle on the server for some amount of time, cursors, by default, "die." This is generally the behavior one wants. The database cleans up a cursor once all of its results have been sent to the client, but if the client doesn't request all of the results, the cursor will languish there, taking up resources. Thus, after a few minutes, the cursor "times out" and the database assumes the client has gotten everything it needs and cleans up its the cursor's resources.
If, for some reason, you need a cursor to hang around for a long time, you
can prevent the database from cleaning it up by using this method.
However, if you make a cursor immortal, you need to iterate through all of
its results (or at least until MongoCursor::dead()
returns TRUE ) or the cursor will hang around the database
forever, taking up resources.
参数
-
liveForever -
If the cursor should be immortal.
返回值
Returns this cursor.
错误／异常
Throws MongoCursorException if this cursor has started iterating.
用户评论:
[#1] fastest963 at gmail dot com [2013-07-09 00:36:49]
Calling immortal(false), in order to remove the NO_TIMEOUT flag from the cursor, seems to crash with "Fatal error: Exception thrown without a stack frame in Unknown on line 0". I'm running PHP 5.2.17 and MongoDB driver 1.1.4.
[#2] iknox {at} info.com [2012-02-14 22:48:03]
Note:: There there is an important distinction between timeout and immortal!
Timeout indicates the time to wait on the _client_ side while immortal sets the cursor on the server side.
It is especially useful for large result sets in sharded environments.