1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
|
<! "@(#)stdmode.so 10.8 (Sleepycat) 11/25/98">
<!Copyright 1997, 1998 by Sleepycat Software, Inc. All rights reserved.>
<html>
<body bgcolor=white>
<head>
<title>Berkeley DB Reference Guide: Locking Subsystem</title>
<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit.">
<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btr
ee,hash,hashing,transaction,transactions,locking,logging,access method,access me
thods,java,C,C++">
</head>
<h3>Berkeley DB Reference Guide: Locking Subsystem</h3>
<p>
<h1 align=center>Standard lock modes</h1>
<p>
The Berkeley DB include files declare two commonly used conflict arrays:
<dl compact>
<p><dt>const u_int8_t db_lock_rw_conflicts[ ];<dd>This is a conflict array for a simple scheme using shared and exclusive
lock modes.
<p><dt>const u_int8_t db_lock_riw_conflicts[ ];<dd>This is a conflict array that involves various intent lock modes (e.g.,
intent shared) that are used for multigranularity locking.
</dl>
<p>
Their associated sizes are DB_LOCK_RW_N and DB_LOCK_RIW_N.
<p>
In addition, the Berkeley DB include file defines the type
<b>db_lockmode_t</b>, which is the type of the lock
modes used with the standard tables above:
<dl compact>
<p><dt>DB_LOCK_NG<dd>not granted (always 0)
<p><dt>DB_LOCK_READ<dd>read (shared)
<p><dt>DB_LOCK_WRITE<dd>write (exclusive)
</dl>
<a href="../../ref/toc.html"><img src="../../images/toc.gif"></a>
</tt>
</body>
</html>
|
